RU2430471C2 - Base station, communication terminal, data transmission and reception method - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: base station has apparatus configured to control frequency units; apparatus configured to determine scheduling information for each frequency unit in order to allocate one or more resource units to a communication terminal having good channel status; apparatus configured generate a control channel containing scheduling information for each frequency unit; and apparatus configured for frequency-division multiplexing of control channels in the system frequency band and transmission thereof. Also, the base station also transmits to the control channel with division into a non-specified control channel subject to decoding by a non-specified communication terminal, and a specified control channel subject to decoding by a communication terminal which was allocated one or more resource units.

EFFECT: high throughput of the system and reduced data loss.

46 cl, 36 dwg

Description

FIELD OF THE INVENTION

The present invention relates to the field of radio communications. More specifically, the present invention relates to a base station, a communication terminal, a method for transmitting and receiving data used in a communication system in which frequency scheduling and multi-carrier transmission are performed.

State of the art

It is becoming increasingly important in the art to implement broadband radio access for efficiently implementing high-speed, high-bandwidth communications. As for downlink channels, the multi-carrier scheme, in particular the Orthogonal Frequency Division Multiplexing (OFDM) scheme, is considered promising from the point of view of high-speed high-bandwidth communication with effective suppression of fading on several propagation paths ( multipath fading), etc. Further, it is also proposed to carry out frequency planning in the next generation system based on an increase in throughput by increasing the frequency utilization efficiency.

As shown in FIG. 1, the frequency band that can be used in the system is divided into several resource blocks (divided into three blocks in the example in the figure), and each of the resource blocks includes one or more subcarriers. A resource block is also called a frequency element. A terminal is assigned one or more resource blocks. In frequency planning, a resource block is assigned to a terminal in which the channel state is good in priority according to the quality of the received signal or channel status information (CQI: Channel Quality Indicator, channel quality indicator) of each resource block of the downlink pilot channel communicated from the terminals, so to maximize the transmission efficiency or throughput of the system as a whole. When carrying out frequency planning, it is necessary to report the content of the planning to the terminal, and the message is carried out using the control channel (which may be called the L1 / L2 control channel (level 1 / level 2), the corresponding control channel, the lower level control channel, etc.). In addition, a modulation scheme (QPSK, 16QAM, 64QAM, etc., for example) used for a scheduled resource block, channel encoding information (channel code rate and similar information) and a hybrid automatic retransmission request (HARQ: Hybrid Auto Repeat ReQuest). A method of dividing a frequency band into several resource blocks and changing a modulation scheme for each resource block is described, for example, in Non-Patent Document 1.

Non-Patent Document 1: P.Chow, J. Chioffi, J. Bingham, "A Practical Discrete Multitone Transceiver Loading Algorithm for Data Transmission over Spectrally Shaped Channel", IEEE Trans.Commun. vol. 43, No.2 / 3/4, February / March / April 1995.

On the other hand, the future next-generation radio access scheme provides for various wide and narrow frequency bands, so it may be necessary for the terminal to use different frequency bands according to location or usage methods. In this case, with respect to the frequency bands that the terminal can receive, various wide and narrow frequency bands may be provided in accordance with the application or cost. In this case, if the frequency planning is carried out properly, an improvement in frequency efficiency and throughput can also be expected. However, since the frequency bands that can be used in existing communication systems are provided in fixed frequency bands, when providing various wide and narrow frequency bands on the base station side and the terminal side, a specific method has not yet been established for the corresponding message of the scheduling content to the terminal or user when the assumption of each combination.

On the other hand, if a specific resource block common to each terminal is fixed for a control channel, then since the state of the terminal channels is usually different for each resource block, there are concerns that the control channel may not be appropriately received depending on the terminal. In addition, when a control channel is distributed across all resource blocks, any terminal can receive a control channel with a specific reception quality. However, it becomes difficult to expect a better quality than that. Therefore, it is desirable to transmit a higher quality control channel to the terminals.

In addition, in the implementation of adaptive modulation and coding (AMC) control, in which modulation schemes and channel coding rates are adaptively changed, the number of characters required for transmitting a control channel is different for each terminal. This is because the amount of information transmitted per character is different depending on the combination of AWS. In addition, future systems are considering the possibility of transmitting and receiving separate signals using multiple antennas provided on both the transmitting side and the receiving side. In this case, for each of the signals transmitted by each antenna, the aforementioned control information, such as scheduling information and the like, may be necessary. Therefore, in this case, the number of symbols necessary for transmitting the control channel varies not only for each terminal, but it is also possible that it is different according to the number of antennas used for the terminal. When the amount of information that must be transmitted using the control channel is different for each terminal, for efficient use of resources it is necessary to use a variable format that can flexibly support changes in the amount of control information. However, there are concerns that the signal processing load on the transmitting side and the receiving side will become large. In contrast, when the format is fixed, it is necessary to reserve a place individual for the control channel, which is adapted for the maximum amount of information. However, when doing this, even if the individual space for the control channel is not occupied, the resources of this part are not used for data transfer, so this contradicts the requirements for efficient use of resources. Therefore, it is desirable to transmit the control channel simply and efficiently.

Disclosure of invention

The present invention has been developed to solve at least one of the above problems, and an object of the invention is to provide a base station, a communication terminal, a data transmission method and a data receiving method for efficiently transmitting a control channel to various terminals in which a frequency band in which communication can be carried out, different in a communication system in which the frequency bands assigned to the communication system are divided into several frequency blocks, each of which includes several resource blocks, each of toryh comprises one or more subcarriers, and the terminal performs communication using one or more frequency blocks.

The base station used in an embodiment of the present invention is used in a communication system in which the frequency band provided to the communication system contains several frequency blocks, each frequency block containing several resource blocks, each of which contains one or more subcarriers. The base station communicates with a communication terminal that uses one or more frequency blocks. Base station includes

means configured to control the correspondence relationship between the frequency bandwidths with which individual communication terminals can communicate and frequency blocks to be assigned to communication terminals;

a frequency scheduler configured to determine scheduling information for each frequency block to assign one or more resource blocks to a communication terminal having a good channel state;

means configured to form a control channel containing scheduling information for each frequency block;

multiplexing means configured to frequency multiplex control channels generated for each frequency block in the frequency band provided to the communication system;

means configured to transmit the output of the multiplexing means using a multi-carrier scheme.

A base station used in one embodiment of the present invention is a multi-carrier base station that schedules frequencies in a frequency band containing multiple resource blocks, each of which contains one or more subcarriers. Base station includes

a frequency scheduler configured to determine scheduling information to assign one or more resource blocks to a communication terminal having a good channel condition based on channel status information reported by individual communication terminals;

means configured to encode and modulate a control channel including a non-specific control channel for decoding by a non-specific communication terminal, and a specific control channel for decoding by a specific communication terminal to which one or more resource blocks are assigned;

multiplexing means configured to temporarily multiplex an unspecified control channel and a specific control channel in accordance with scheduling information; and

means configured to transmit the output of the multiplexing means using a multi-carrier scheme.

A base station used in one embodiment of the present invention is a multi-carrier base station that schedules frequencies in a frequency band including several resource blocks, each of which contains one or more subcarriers. Base station includes

a frequency scheduler configured to determine scheduling information to assign one or more resource blocks to a communication terminal having a good channel condition based on channel status information reported by individual communication terminals;

multiplexing means configured to multiplex the control channel and the data channel in accordance with scheduling information; and

means configured to transmit the output of the multiplexing means using a multi-carrier scheme. A control channel for decoding by a specific communication terminal is mapped to a frequency band containing several resource blocks in a distributed manner.

A base station used in one embodiment of the present invention is a multi-carrier base station that schedules frequencies in a frequency band containing multiple resource blocks, each of which contains one or more subcarriers. Base station includes

a frequency scheduler configured to determine scheduling information to assign one or more resource blocks to a communication terminal having a good channel state based on channel status information reported by the individual communication terminals;

multiplexing means configured to multiplex the control channel and the data channel in accordance with scheduling information; and

means configured to transmit the output of the multiplexing means using a multi-carrier scheme. The control channel for decoding by the instantiated communication terminal is limitedly mapped to the resource block assigned to the instantiated communication terminal.

A base station used in one embodiment of the present invention is a multi-carrier base station that schedules frequencies in a frequency band containing multiple resource blocks, each of which contains one or more subcarriers. Base station includes

a frequency scheduler configured to determine scheduling information to assign one or more resource blocks to a communication terminal having a good channel state based on channel status information reported by the individual communication terminals;

means configured to encode and modulate a control channel including a non-specific control channel for decoding by a non-specific communication terminal, and a specific control channel for decoding by a specific communication terminal to which one or more resource blocks are assigned;

multiplexing means configured to temporarily multiplex an unspecified control channel and a specific control channel in accordance with scheduling information; and

means configured to transmit the output of the multiplexing means using a multi-carrier scheme. The non-specific control channel contains information indicating a transmission format of the non-specific control channel.

According to the present invention, it becomes possible to efficiently transmit the control channel to various terminals, in which the width of the frequency bands by which communication can be carried out is different in a communication system in which each of several frequency blocks forming the system frequency band includes several resource blocks, each of which contains one or more subcarriers.

Brief Description of the Drawings

1 is a diagram for explaining frequency planning.

2 is a diagram showing a frequency band used in an embodiment of the present invention.

3A shows an incomplete block diagram of a base station in accordance with an embodiment of the present invention (1).

FIG. 3B shows an incomplete block diagram of a base station in accordance with an embodiment of the present invention (2).

4A is a diagram showing signal processing elements in one frequency block.

4B is a diagram showing signal processing elements in a control channel.

4C is a diagram showing signal processing elements in a control channel.

Fig. 4D is a diagram showing signal processing elements in a control channel.

4E is a diagram showing signal processing elements in a control channel.

5A is a diagram showing examples of an information element of control signaling channels.

5B is a diagram showing a localized FDM scheme and a distributed FDM scheme.

Fig. 5B is a diagram showing an L1 / L2 control channel in which the number of symbols changes in accordance with the number of simultaneously multiplexed users.

6 is a diagram showing error correction coding elements.

7A is a diagram showing an example of displaying data channels and control channels.

7B is a diagram showing an example of displaying data channels and control channels.

7C is a diagram showing examples of the format of the L1 / L2 control channel.

7D is a diagram showing examples of the format of the L1 / L2 control channel.

FIG. 7E is a diagram showing display examples of an L1 / L2 control channel in a six-sector configuration.

FIG. 7F is a diagram showing approximately multiplexing schemes of the non-specific control channel.

7G is a diagram showing an example of displaying data channels and control channels.

FIG. 7H is a diagram showing an example of displaying data channels and control channels.

7I is a diagram showing an example of displaying data channels and control channels.

FIG. 7J is a diagram showing a method of grouping users in a cell.

On figa shows an incomplete block diagram of the terminal used in the embodiment of the present invention.

On figv shows an incomplete block diagram of the terminal used in the embodiment of the present invention.

On figs shows an incomplete block diagram related to the receiving module of the terminal.

Fig. 9 is a flowchart showing an example of operation in accordance with an embodiment of the present invention.

10A is a diagram showing a relationship between error checking entities and channel coding modules.

10B is a diagram showing a relationship between error checking entities and channel coding modules.

10C is a diagram showing a relationship between error checking entities and channel coding modules.

10D is a diagram showing an example of a method for reducing the amount of information related to uplink information.

10E is a diagram showing an example of operation when frequency hopping is performed.

11 is a diagram showing a block diagram of an example of operation and a frequency band in an embodiment of the present invention.

12 is a diagram showing a block diagram of another example of operation and frequency band in an embodiment of the present invention.

13 is a diagram showing a method by which TPC is performed.

14 is a diagram showing a method by which AMC is controlled.

Notation list

31: frequency block assignment control module

32: frequency planning module

33-x: module for generating a control signal channel in the frequency block x

34th: data channel forming module in the frequency block x

35: module for the formation of the broadcast channel (or channel call)

1-x: the first multiplexing module in the frequency block x

37: second multiplexing module

38: third multiplexing module

39: another channel shaping module

40: inverse fast Fourier transform (IFFT) module

41: cyclic prefix injection module

41: module for the formation of non-specific control channel

42: module for the formation of a specific control channel

43: multiplexing module

81: carrier frequency tuning module

82: filter module

83: module cyclic prefix removal

84: fast Fourier transform module (FFT)

85: CQI determination module

86: broadcast channel decoding module

87-0: non-specific control channel decoding module (part 0)

87: non-specific control channel decoding module

88: specific control channel decoding module

89: data channel decoding module

The implementation of the invention

According to an embodiment of the present invention, frequency scheduling is performed for each frequency, and a control channel for reporting scheduling information is generated for each frequency block in accordance with the minimum frequency bandwidth. Accordingly, the control channel can be effectively transmitted to various communication terminals, for which the width of the frequency bands by which communication can be carried out is different. A communication terminal is typically a mobile terminal or a mobile station, however, it may be a fixed terminal or a fixed station. A communication terminal may be called a user device.

The control channels generated for each frequency block can be frequency multiplexed in accordance with a predefined frequency hopping pattern. This can equalize the quality of communication between communication terminals and between frequency blocks.

A broadcast channel may be transmitted using a frequency band, which is a band containing the center frequency of a frequency band provided to a communication system that has a width corresponding to one frequency block. This allows any communication terminal that is trying to access the communication system to connect to the communication system in a simple manner by receiving a minimum band signal in the vicinity of the center frequency.

The call channel is also transmitted using a frequency band, which is a band including the center frequency of the frequency band provided to the communication system, and which has a width corresponding to one frequency block. This makes it possible to combine the standby reception frequency band and the frequency band to search for a cell, since it is preferable from the point of view that the frequency tuning execution number can be reduced as much as possible.

From the point of view of uniform use of the entire frequency band, the call channel for calling the communication terminal may be transmitted using the frequency block assigned to the communication terminal.

According to an embodiment of the present invention, the control channel can be divided into a non-specific control channel for decoding by the non-specific communication terminal and a specific control channel for decoding by the specific communication terminal to which one or more resource blocks are assigned, and these channels can be encoded and modulated apart. The non-specific control channel and the specific control channel undergo temporary multiplexing according to scheduling information so that the control channel is transmitted using a multi-carrier scheme. Accordingly, the control channel can be efficiently transmitted without unnecessarily expensive resources using a fixed format, even if the amount of control information is different for each communication terminal.

An unspecified control channel may be mapped to a frequency band in a distributed manner, and a specific control channel relating to a specific communication terminal may be mapped to a resource block assigned to a specific communication terminal in a limited manner. Along with the fact that the quality of the non-specific control channel can be kept equal to or greater than a certain level for all users, the quality of the specific control channel can be made good. This is because the instantiated control channel is mapped to a resource block with a good channel state for each instantiated communication terminal.

The downlink pilot channel may also be mapped to several resource blocks assigned to several communication terminals in a distributed manner. By distributing the pilot channel over a wide frequency band, the accuracy of channel estimation and the like can be improved.

According to an embodiment of the present invention, from the point of view of maintaining or improving the reception quality of a control channel including non-specific and specific control channels, transmission power of the non-specific control channel is controlled, and transmission power and adaptive modulation and coding are controlled in the specific control channel, or both.

The transmission power of the non-specific control channel can be controlled so that the specific communication terminal to which the resource block is assigned can receive the non-specific control channel with high quality. This is possible because although each user or communication terminal that receives an unspecified control channel is required to attempt demodulation, it is necessary that ultimately only the user to whom the resource block is actually assigned successfully demodulates.

The non-specific control channel may include information about a modulation scheme or coding scheme, or both, used in a particular control channel. Since the combination of the modulation scheme and the coding scheme for the non-specific control channel is fixed, the user to whom the resource block is assigned can obtain a modulation scheme, coding scheme, etc. for a specific control channel by demodulating the non-specific control channel. By this method, adaptive modulation and coding in the control channel can be controlled with respect to a part of a specific control channel, so that the reception quality of such a part can be improved.

When performing transmission power control and adaptive modulation and coding control for a control channel, the total number of modulation schemes and coding schemes for a particular control channel may be provided less than the total number of combinations of modulation schemes and coding schemes for a common data channel. This is because although the required quality can be obtained by controlling adaptive modulation and coding, the required quality can be obtained by controlling the transmission power.

OPTION 1

2 shows a frequency band used in an embodiment of the present invention. Although specific numerical values are used for description purposes, the values are merely examples and various values may be used. The frequency band (entire frequency band) provided to the communication system has a width of 20 MHz, for example. The entire frequency band includes four frequency blocks 1-4, and each frequency block includes several resource blocks, each of which contains one or more subcarriers. The example shown in the figure schematically shows that each frequency block contains many subcarriers. In the present embodiment, four types of frequency bands of 5 MHz, 10 MHz, 15 MHz and 20 MHz are provided for communication. A terminal uses one or more frequency blocks to communicate using one of four frequency bands. A terminal communicating in a communication system may be able to communicate using any of the four frequency bands, or may be able to communicate using only certain frequency bands. Or, instead of preparing such a plurality of kinds of frequency bands, a standard can be defined so that any communication terminal can communicate in the entire frequency band of the system. In order to provide a more general description, the following embodiments describe a case in which a selection of four types of frequency bands is provided. However, it should be understood that the present invention is applicable regardless of the presence or absence of such a choice of frequency bands.

In the present embodiment, a control channel (L1 / L2 control signal channel or low level control channel) with a minimum frequency bandwidth (5 MHz) is generated for reporting data channel planning information (common data channel), and a control channel is independently provided for each frequency block . For example, when a terminal communicating using a frequency band of 5 MHz communicates using frequency block 1, the terminal receives a control channel prepared for frequency block 1 so that the terminal can receive scheduling content. Which frequency unit the terminal can use for communication can be communicated in advance using a broadcast channel, for example. In addition, after the start of communication, the used frequency block can be changed. When a terminal communicating using a frequency band of 10 MHz communicates using frequency blocks 1 and 2, the terminal uses two adjacent frequency blocks and receives both control channels prepared for frequency blocks 1 and 2 so that the terminal can receive scheduling content in the entire range of 10 MHz. A terminal that communicates using a frequency band of 15 MHz uses three adjacent frequency blocks, and when a terminal communicates using frequency blocks 1, 2, and 3, the terminal receives all control channels prepared for frequency blocks 1, 2, and 3 so that it can receive planning content over the entire 15 MHz band. A terminal that communicates using a frequency band of 20 MHz receives all control channels provided for all frequency blocks so that the terminal can receive scheduling content in the range of 20 MHz.

The figure shows four discrete blocks in a frequency block related to a control channel. This shows that the control channel is distributed and mapped to several resource blocks in the frequency block. A specific example of the display of the control channel is described below.

3A shows an incomplete block diagram of a base station in accordance with an embodiment of the present invention. 3A shows a frequency block assignment control module 31, a frequency scheduling module 32, a control signal channel generating module 33-1 and a data channel generating module 34-1 in the frequency block 1, ..., a 33-M control signal channel generating module and a module 34-M data channel generation in frequency block M, broadcast channel (or call channel) generation module 35, first multiplexing module 1-1 for frequency block 1, ..., first 1-M multiplexing module for frequency block M, second mult module 37 multiplexing module, third multiplexing module 38, another channel generating module 39, Inverse Fast Fourier Transform module 40, and cyclic prefix introducing module 41.

Based on the information related to the maximum bandwidth by which communication communicated by the terminal (which may be a mobile terminal or a fixed (stationary) terminal) can be made, the frequency block assignment control module 31 checks the frequency block to be used by the terminal. The frequency block assignment control module 31 controls the correspondence relationship between the individual terminals and the frequency blocks and reports the contents to the frequency scheduling module 32. Which frequency block can be used for communication by a terminal that can communicate using a frequency band can be communicated in advance using a broadcast channel. For example, a broadcast channel may allow a user communicating using a 5 MHz frequency band to use any frequency band of frequency blocks 1, 2, 3, and 4, or the use may be limited to any of them. In addition, a user who communicates using the 10 MHz frequency band is allowed to use a combination of two adjacent frequency blocks, such as frequency blocks (1, 2), (2, 3) or (3, 4). All of them may be authorized for use, or use may be limited to any of the combinations. A user who communicates using a bandwidth of 15 MHz is allowed to use a combination of three adjacent frequency blocks, such as frequency blocks (1, 2, 3) or (2, 3, 4). Both may be authorized for use, or use may be limited to any combination. A user who communicates using the 20 MHz frequency band is allowed to use all frequency blocks. As described below, the frequency blocks used can be changed after the start of communication according to a predefined frequency hopping pattern.

The frequency scheduling unit 32 performs frequency scheduling in each of several frequency blocks. Frequency scheduling in one frequency block determines scheduling information so as to assign a resource block, preferably to a terminal having a good channel state, based on CQI information about the channel state of each resource block reported by the terminals.

Module 33-1 generating the control signal channel in the frequency block 1 for configuring the control signal channel to inform the terminals of the scheduling information in the frequency block 1 uses resource blocks only in the frequency block 1. Similarly, in another frequency block, the control signal channel for communicating with the terminals scheduling information in the frequency block is generated using resource blocks only in the frequency block.

The data channel generation module 34-1 in the frequency block 1 generates a data channel to be transmitted using one or more resource blocks in the frequency block 1. Since the frequency block 1 can be shared by one or more terminals (users), in the example shown in the figure, N modules 1-1-1-N of data channel formation are provided. Similarly, for another frequency block, data channels of the terminal are formed that share the frequency block.

The first multiplexing module 1-1 for the frequency block 1 multiplexes the signals related to the frequency block 1. This multiplexing at least includes frequency multiplexing. How the control signal channel and the data channel are multiplexed is described below. Similarly, another first 1x multiplexing unit multiplexes the control signal channel and the data channel transmitted using the frequency block x.

The second multiplexing module 37 performs an operation to change the position ratio among various 1-x (x = 1, ..., M) multiplexing modules along the frequency axis in accordance with a predefined frequency hopping pattern. This function is described in the second embodiment.

The broadcast channel (or call channel) generating unit 35 generates broadcast information, such as overhead, communicated to terminals connected to the base station. The control information may contain information indicating the relationship between the maximum frequency band by which the terminal can communicate and the frequency block that the terminal can use. When a suitable frequency block changes in various ways, the broadcast information may include information defining a frequency hopping pattern indicating how the frequency block changes. In this case, the call channel may be transmitted using the same frequency band as the broadcast channel, or may be transmitted using the frequency block used in each terminal.

Module 39 forming another channel generates a channel other than the signal control channel and the data channel. For example, another channel generating unit 39 generates a pilot channel. A pilot channel or pilot signal is, in some way, a reference signal, which is known on the transmitting side and the receiving side, and may be called a reference signal, a known signal, preparing a signal, and the like.

The third multiplexing module 38 multiplexes the control signal channels and data channels of each frequency block, and a broadcast channel and / or other channel, if necessary.

The inverse fast Fourier transform module 40 performs the inverse fast Fourier transform on the signal output from the third multiplexing unit 38 to perform OFDM modulation.

The cyclic prefix introduction module 41 (CP, cyclic prefix) adds a guard interval to a symbol after OFDM modulation to form a transmitted symbol. The transmitted symbol may be formed by adding a data sequence at the end (or beginning) of the OFDM symbol to the beginning (or end).

FIG. 3B shows the elements following the CP insertion module 41 shown in FIG. 3A. As shown in the figure, the symbol into which the guard interval is entered is amplified to the appropriate power by the power amplifier after the processes of digital-to-analog conversion, frequency conversion, bandwidth limitation, etc. in the RF (radio frequency) transmission circuit, and the signal is transmitted through a duplexer and a transmitting and receiving antenna.

Although not essential for the present invention, in the present embodiment, when performing reception, antenna diversity reception is performed by two antennas. The uplink signal received by the two antennas is supplied to the uplink signal receiving unit.

On figa shows the elements of the signal processing in one frequency block (x-th frequency block), "x" is an integer equal to or greater than 1 and equal to or less than M. In general, the figure shows the module 33 of the formation of the signal the control channel and the module 34 of the formation of the data channel related to the frequency block x, modules 43-A and 43-B multiplexing and module 1 multiplexing. The control signal generation channel generation module 33 includes a non-specific control channel generation module 41 and one or more modules 42-A, 42-B, ... of forming a specific control channel.

In the control signal channel, the non-specific control channel generation module 41 carries out channel coding and multi-level modulation of a part of the non-specific control channel (which may be called non-specific control information), which each terminal using the frequency block must decode and demodulate and outputs it.

Each of the modules 42-A, 42-B, ... of forming a specific control channel implements channel coding and multi-level modulation of a part of the specific control channel (which may be called specific control information) in the control signal channel, which each terminal assigned to decode and demodulate one or more resource blocks in a frequency block, and outputs it.

Modules xA, B, ... of forming a data channel carry out channel coding and multilevel modulation of data channels addressed to individual terminals A, B, ..., respectively. Information about channel coding and multi-level modulation is included in the specific control channel.

The 43-A, 43-B, ... multiplexing module associates the instantiated control channel and the data channel to the resource block for each terminal to which the resource block is assigned.

As indicated above, the encoding (and modulation) of the non-specific control channel is carried out in the module 41 for the formation of the non-specific control channel, and the encoding (and modulation) of the specific control channel is carried out in the modules 42-A, 42-B, ... of forming the specific control channel separately. Therefore, in the present embodiment, as shown in principle in FIG. 6, the non-specific control channel includes pieces of information of all users who are assigned a frequency block x, and these pieces of information become an object for coding with error correction in general.

In another embodiment, the non-specific control channel may also be error-corrected encoded for each user. In this case, since each user cannot unambiguously determine which block contains the information of this user in blocks that have individually passed the error correction coding, it is necessary to decode all the blocks. In this other embodiment, since the encoding processing for each user is closed, it is relatively easy to enter and change users. Each user needs to decode and modulate non-specific control channels for all users.

On the other hand, a specific control channel contains only information about the user to whom the resource block is actually assigned, so that error correction coding is carried out for each user. The resource block assigned to which user is determined by decoding and demodulating the non-specific control channel. Therefore, it is not necessary that all users decode a specific control channel; it is only necessary that the user to whom the resource block is assigned decodes. At the same time, during communication, the channel code rate and the modulation scheme for a specific control channel are changed as necessary, and the channel code rate and the modulation scheme for an unspecified control channel can be fixed. However, it is desirable to control transmission power (TPC) to ensure that signal quality is equal to or greater than a predetermined level. A specific control channel is transmitted using a good resource block after error correction coding is performed. Therefore, the amount of downstream data can be reduced to some extent by performing puncturing.

FIG. 5A shows an example of types and information elements of downlink control signal channels. The downstream control signal channels include a broadcast channel (BCH), a separate L3 signal channel (high-level control channel or high-level control channel), and an L1 / L2 control channel (low-level control channel). The L1 / L2 control channel may contain not only information for downlink data transmission, but also information for uplink data transmission. The following briefly describes the information elements transmitted by each channel.

Broadcast channel

A broadcast channel is used to report constant information or information that changes at a low speed in a cell to a communication terminal (which may be a mobile terminal or a fixed terminal, or may be called a user device). For example, information that may change with a period of about 1000 ms (1 second) may be reported as broadcast information. The broadcast information may include a L1 / L2 downlink control transmission format, a maximum number of simultaneously assigned users, resource block placement information, and MIMO scheme information.

The transmission format is determined by the data modulation scheme and the channel coding rate. Instead of a channel coding rate, a data size may be reported. This is because the channel coding rate can be unambiguously derived from the data modulation scheme and the data size.

The maximum number of concurrently assigned users indicates the maximum number that can be multiplexed in 1 TTI (transmission time interval) using one or more of the FDM, CDM, and TDM schemes. The number may be the same or different for the uplink and downlink.

Information about the location of the resource block is information for determining the positions of the resource blocks on the frequency and time axes used in the cell. In the present embodiment, as the frequency division multiplexing (FDM) scheme, two kinds can be used, which are the localized FDM scheme and the distributed FDM scheme. In a localized FDM scheme, the user is locally assigned continuous frequency bands with a good channel state along the frequency axis based on priority. This scheme has advantages for user communication with low mobility, transmission of high quality data and high bandwidth, etc. In a distributed FDM scheme, a downward signal is generated so as to intermittently contain several frequency components located in a wide frequency band. This scheme has advantages for user communication with high mobility, periodic transmission of small data such as voice packets (VolP, Voice over IP, Internet telephony), etc. Whatever scheme is used, resource assignment for frequency resources is done according to information indicating continuous frequency bands or several discrete frequency components.

As shown on the upper side of FIG. 5B, when the resource is defined as “4” in the localized FDM scheme, for example, the resource of the physical resource block number 4 is used. In the distributed FDM scheme shown on the lower side of FIG. 5B, when the resource is defined as “4 ”, The two left halves of the physical resource blocks with numbers 2 and 8 are used. In the example shown in the figure, one physical resource block is divided into two. The numbering and partition numbers in the distributed FDM scheme may vary for each cell. Thus, information about the location of the resource block is communicated to the communication terminals in the cell by the broadcast channel.

When several antennas are provided in the base station, the MIMO circuit information indicates which circuit is being implemented: single-user MIMO circuit (SU-MIMO, Single User - Multi Input Multi Output, single-user circuit with many inputs and outputs) or multi-user MIMO circuit (MU-MIMO, Multi - User MIMO). The SU-MIMO circuit is a circuit for communicating with a single communication terminal having multiple antennas, and the MU-MIMO circuit is a circuit for communicating with multiple communication terminals having one antenna at a time.

Separate signal channel L3

A separate signal channel L3 is also used to inform the communication terminal of information that changes at a low speed, with a period of 1000 ms, for example. Although a broadcast channel is sent to all communication terminals in a cell, a separate signal channel L3 is sent only to individualized communication terminals. A separate L3 signaling channel includes an FDM scheme type and fixed scheduling information. A separate signaling channel L3 can also be classified as an individualized control channel.

The type of FDM scheme determines which circuit from the localized FDM scheme and the distributed FDM scheme is used to multiplex individualized individual communication terminals.

The fixed scheduling information determines, when carrying out constant scheduling, the transmission format (data modulation scheme and channel code rate) of the upstream or downstream data channel, the resource block to be used, etc.

Control channel L1 / L2

The L1 / L2 downlink control channel may contain not only information related to downlink data transmission, but also information related to uplink data transmission. Information related to downstream data transmission can be divided into part 0, part 1, part 2a and part 2b. Part 1 and part 2a can be classified as non-individualized control channels, and part 2b is classified as an individualized control channel.

Part 0

Part 0 contains information indicating the transmission format of the L1 / L2 control channel (modulation scheme and channel coding rate, the number of simultaneously assigned users, or the number of control bits in general). When the transmission format of the L1 / L2 control channel is signaled by the broadcast channel, part 0 may contain the number of simultaneously assigned users (or the number of control bits in general).

The number of characters required for the L1 / L2 control channel depends on the number of simultaneously multiplexed users and the reception quality of the multiplexed users. As shown on the left side of FIG. 5C, the number of characters of the L1 / L2 control channel is usually set to be large enough. When the number of characters is changed, it can be controlled for a period of about 1000 ms (1 second), for example, according to the transmission format of the L1 / L2 control channel reported by the broadcast channel. However, when the number of simultaneously multiplexed users is small, as shown on the right side of FIG. 5C, the number of characters needed for the control channel becomes small. Therefore, when the number of simultaneously assigned users and the reception quality of multiplexed users changes in a short period, there is a case in which there is an excessive waste of resources in the L1 / L2 control channel, which is provided for sufficiently large.

To reduce the unnecessary waste of resources of the L1 / L2 control channel, the modulation scheme, the channel coding rate and the number of simultaneously assigned users (or the number of control bits as a whole) can be communicated in the L1 / L2 control channel. When the modulation scheme and the channel coding rate are reported in the L1 / L2 control channel, the modulation scheme and the channel coding rate may change with a shorter period than that communicated by the broadcast channel.

Part 1

Part 1 contains a call indicator (PI, paging indicator). Each communication terminal demodulates a call indicator to check whether a call is being made to that terminal.

Part 2a

Part 2a contains downlink resource assignment information, assigned time duration, and MIMO information.

The resource assignment information of the downlink data channel defines a resource block containing the downlink data channel. Various methods known in the art can be used to determine a resource block. For example, a bit map scheme, a tree-like number scheme, etc. can be used.

The assigned time duration indicates how long the downlink data channel is continuously transmitted. A change in the content of the resource assignment most often corresponds to a change in each TTI. In terms of reducing overhead, a data channel may be transmitted with the same resource assignment content across multiple TTIs.

The MIMO information determines, when using the MIMO scheme for communication, the number of antennas, the number of streams, and the like. The number of streams may also be called the number of information series.

Moreover, although it is not necessary that part 2a contains user identification information, it may be included all or part of it.

Part 2b

Part 2b contains precoding information using the MIMO scheme, a downlink data transmission format, hybrid retransmission control (HARQ) information and CRC (cyclic redundancy check, code sum) information.

The precoding information when using the MIMO scheme determines the weights applied to each of several antennas. By adjusting the weights applied to each antenna, the directivity of the communication signal is adjusted.

The transmission format of the downlink data channel is determined by the modulation scheme and the code rate of the channel. Instead of a channel coding rate, a data size or useful information size may be reported. This is due to the fact that the channel coding rate can be unambiguously derived from the data modulation scheme and data sizes.

Hybrid Retransmission Control Information (HARQ: Hybrid Automatic Repeat Request) contains the information needed to control the retransmission of downstream packets. More specifically, the retransmission control information comprises a process number, redundancy version information indicating a method of combining packets, and a new data indicator for distinguishing between a new packet and a retransmitted packet.

The CRC information indicates, when using the code sum verification method for error determination, a CRC detection bit in which user identification information (UE-ID) is collapsed.

Information related to upstream data transmission can be classified into four types from part 1 to part 4, as described below. Although these pieces of information can in principle be defined as a non-specific control channel, they can also be transmitted as a specific control channel for a communication terminal to which resources are assigned for the downlink data channel.

Part 1

Part 1 contains transmission confirmation information for the previous uplink data channel. Transmission confirmation information indicates acknowledgment (ACK), indicating that there are no errors in the packet or that there is an error, but it is in the acceptable range, or indicates a negative acknowledgment (NACK, negative acknowledgment) indicating that there are errors in the packet that exceed the allowable range.

Part 2

Part 2 contains resource allocation information for the future uplink data channel, the transmission format of the uplink data channel, transmission power information, and CRC information.

The resource assignment information defines a resource block that can be used to transmit the uplink data channel. Various methods known in the art can be used to determine the resource block. For example, a bitmap scheme, a tree number scheme, and the like may be used.

The transmission format of the uplink data channel is determined by the data modulation scheme and the channel coding rate. Instead of a channel coding rate, a data size or useful information size may be reported. This is due to the fact that the channel coding rate can be unambiguously derived from the data modulation scheme and data sizes.

The transmit power information indicates how high the power with which the uplink data channel is to be transmitted.

The CRC information indicates, when using the code sum verification method for error determination, a CRC detection bit in which user identification information (UE-ID) is collapsed. Moreover, in the response signal (L1 / L2 downlink control channel) for the random access channel (RACH, random access channel), the random identifier of the RACH preamble can be used as a UE-ID.

Part 3

Part 3 contains a bit for controlling the distribution of transmission over time. This is a control bit for synchronizing communication terminals in a cell.

Part 4

Part 4 contains information on the transmit power of the communication terminal. This information indicates how high the power that the communication terminal, to which resources are not assigned for transmitting the uplink data channel, should be used to transmit the uplink control channel for C downlink channel CQI, for example.

Like FIG. 4A, FIG. 4E shows signal processing elements in a single frequency block. However, in contrast to FIG. 4A, corresponding portions of control information are specifically shown. 4A and 4E, the same reference signs indicate the same elements. In the figure, “mapping in a resource block” indicates that the mapping is limited to one or more resource blocks assigned to a particular communication terminal. “Display outside the resource block” means that the display is carried out in the entire area of the frequency block containing many resource blocks. Information (parts 1-4) related to uplink data transmission in the L1 / L2 control channel is transmitted when resources are assigned to the downstream data channel using the resource as a specific control channel, and information is transmitted when resources are not assigned, in the entire frequency block as an non-individualized control channel.

On figa shows an example of the display of data channels and control channels. A display example is shown in the figure for one frequency block and for one subframe, and generally refers to the content of the output of the first multiplexing unit 1 (a pilot channel and the like are multiplexed by the third multiplexing unit 38). One subframe may correspond to one transmission time interval (TTI) or correspond to several TTIs, for example. In the example shown in the figure, the frequency block contains seven resource blocks RB1-RB7. Seven resource blocks are assigned to terminals having a good channel condition by the frequency scheduling module 32 shown in FIG. 3A.

In general, the non-specific control channel and the like, the pilot channel and the like, and the data channel and the like undergo temporary multiplexing. The non-specific control channel is mapped to the entire frequency block in a distributed manner. That is, the non-specific channel is distributed over the entire frequency band occupied by seven resource blocks. In the example shown in the figure, the non-specific control channel and other control channels (excluding the specific control channel) undergo frequency multiplexing. Other channels may include a synchronization channel and the like, for example (an unspecified control channel may be defined to include a synchronization channel and the like without differentiation between the non-specific control channel and other control channels). In the example shown in the figure, the non-specific control channel and the other control channel undergo frequency multiplexing so that each of them includes several frequency components that are located at certain intervals. Such a multiplexing scheme is called a frequency division multiplexing (FDM). The interval between the frequency components may be the same or may be different. In any case, it is necessary that the non-specific control channel be distributed over the entire range of one frequency block.

In the example shown in the figure, a pilot channel and the like are also mapped to the entire range of the frequency block. From the point of view of correctly performing channel estimation, etc. for different frequency components, it is desirable that the pilot channel be mapped to a wide range, as shown in the figure.

In the example shown in the figure, resource blocks RB1, RB2, and RB4 are assigned to user 1 (UE1), resource blocks RB3, RB5, and RB6 are assigned to user 2 (UE2), and resource block RB7 is assigned to user 3 (UE3). As indicated above, such assignment information is contained in the non-specific control channel. In addition, the instantiated user control channel 1 is mapped to the head of the resource block RB1 in the resource blocks assigned to the user 1. The instantiated user control channel 2 is mapped to the head of the resource block RB3 in the resource blocks assigned to the user 2. The instantiated user control channel 3 is distributed in the head part of the resource block RB7 in the resource blocks assigned to the user 3. It should be noted that the sizes occupied by the specific user control channels lei 1, 2 and 3, the figure shows unequal. This means that the amount of information of a particular control channel may vary according to users. The specific control channel is locally distributed within the resource block assigned to the data channel. In this, the scheme differs from the distributed FDM in which the distribution is carried out over various resource blocks in a distributed manner. This distribution scheme is also called localized frequency division multiplexing (localized FDM).

FIG. 7B shows another example of a non-specific control channel allocation. Although the instantiated user channel 1 (UE1) is mapped to only one resource block RB1 in FIG. 7A, it is discretely mapped to all resource blocks RB1, RB2, and RB4 (all resource blocks assigned to user 1) in a distributed manner using the FDM scheme. In addition, the instantiated user control channel 2 (UE2) is also different from the case shown in FIG. 7A and is mapped to all resource blocks RB3, RB5 and RB6. The specific control channel and the common user data channel 2 are time division multiplexed. Accordingly, the specific control channel and the common data channel of each user can be multiplexed using a time division multiplexing (TDM) scheme and / or a frequency division multiplexing scheme (including a localized FDM scheme and a distributed FDM scheme) throughout or parts of one or more resource blocks assigned to a user. By mapping the instantiated control channel to two or more resource blocks, the frequency diversity effect can also be expected for the instantiated control channel, so that the signal quality of the instantiated control channel can be further improved.

The following describes the specific formats of part 0 in the L1 / L2 control channel.

Fig. 7C is an example showing the formats of the L1 / L2 control channel when reporting the number of characters (or the number of simultaneously assigned users) of the L1 / L2 control channel. When the communication terminal uses the modulation scheme and coding rate (MCS: Modulation and Coding Scheme) communicated by the broadcast channel, the number of characters required for the L1 / L2 control channel changes according to the number of simultaneously assigned users. To determine it, control bits are provided (two bits in FIG. 7C) as information of part 0 of the L1 / L2 control channel. For example, when the control bits 00 are reported as part 0 information, for example, the communication terminal can determine that the number of characters of the L1 / L2 control channel is 100 by decoding the control bits. In this case, the two header bits in Fig. 7C correspond to part 0, and the variable control channel corresponds to the non-specific control channel (corresponding to part 1 and part 2a in the case of a downlink). In addition, although in FIG. 7C, the MCS is signaled by the broadcast channel, the MCS can be signaled by the L3 signal channel.

Fig. 7D is an example showing the format of the L1 / L2 control channel when the number of simultaneously assigned users of each MCS is reported by part 0. When using the corresponding MCS from the predefined types of MCS in accordance with the reception quality of the communication terminal, the number of characters required for the L1 control channel / L2, changes in accordance with the reception quality of the communication terminal. To determine this, control bits are provided (eight bits in FIG. 7D) as part of the information of part 0 of the L1 / L2 control channel. Fig.7D shows a case, as an example, in which there are four types of MCS and the maximum value of the number of simultaneously assigned users of each MCS is three. Since the number of simultaneously assigned users is 0-3, this information can be represented by two bits (00 = 0 user, 01 = 1 user, 10 = 2 user, 11 = 3 user). Since two bits are needed for each MCS, part 0 becomes eight-bit in this case. For example, when reporting 01100001 as part 0 information, the communication terminal may determine the control information (part 2a in the case of a downlink) in accordance with its reception quality based on the control bits.

FIG. 7E is an example showing the mapping of information bits (part 0) in the L1 / L2 control channel in the case of a three-sector configuration. In the case of a three-sector configuration, three kinds of patterns can be prepared for transmitting bits of information (part 0) indicating the transmission format of the L1 / L2 control channel and assigned to each sector so that the patterns do not overlap in the frequency domain. By selecting a pattern so that the transmission patterns of adjacent sectors (or cells) are different from each other, an effect of interference coordination can be achieved.

7F shows various examples of multiplexing methods. Although in the above examples, various non-specific control channels are multiplexed using a distributed FDM scheme, various appropriate multiplexing methods such as code division multiplexing and time division multiplexing (TDM) can be used. 7F (1) shows a case in which multiplexing is performed according to a distributed FDM scheme. Using numbers 1, 2, 3, and 4, defining several discrete frequency components, the signals of each user can be appropriately orthogonalized. However, there is no need for regular placement, as in this example. In addition, when using different rules in adjacent cells, the level of interference in the implementation of power control can be made random. FIG. 7F (2) shows a case in which multiplexing is performed according to a code division multiplexing (CDM) scheme. Using codes 1, 2, 3, and 4, each user's signals can be appropriately orthogonalized. 7F (3) shows a case where the number of multiplexed users changes by three in a distributed FDM scheme. By redefining the numbers 1, 2, and 3 to define several discrete frequency components, the signals of each user can be appropriately orthogonalized. When the number of concurrently assigned users is less than the maximum number, as shown in FIG. 7F (4), the base station can increase the transmit power of the downlink control channel. In addition, a hybrid of CDM and FDM can be applied.

On figa shows an incomplete block diagram of a mobile terminal used in an embodiment of the present invention. 8A shows a carrier frequency tuning module 81, a filtering module 82, a cyclic prefix removal (CP) module 83, a fast Fourier transform (FFT) module 84, a CQI determination module 85, a broadcast channel (or call channel) decoding module 86, a module 87-0 decoding of the non-specific control channel (part 0), module for decoding the non-specific control channel 87, module 88 for decoding the specific control channel and decoding module 89 of the data channel.

The carrier frequency tuning module 81 adjusts the center frequency of the reception frequency band accordingly so as to be able to receive the signal of the frequency block assigned to the terminal.

Filtering module 82 filters the received signal.

The cyclic prefix removal unit 83 removes the guard interval from the received signal to extract the effective portion of the symbol from the received symbol.

The Fast Fourier Transform Module (FFT) performs a fast Fourier transform on the information contained in an effective symbol for performing OFDM demodulation.

The CQI determination module 85 determines the received power level of the pilot channel contained in the received signal to feed the determination result back to the base station as CQI information about the channel status. CQI is performed for each of all resource blocks in the frequency block, and all of them are reported to the base station.

The broadcast channel (or call channel) decoding unit 86 decodes the broadcast channel. When a call channel is present, it is also decoded.

The non-specific control channel decoding unit 87-0 (part 0) decodes part 0 information in the L1 / L2 control channel. With part 0, it becomes possible to determine the transmission format of the non-specific control channel.

The non-specific control channel decoding unit 87 decodes the non-specific control channel contained in the received signal to extract scheduling information. The scheduling information contains information indicating whether a resource block is assigned to a common data channel addressed to the terminal, and information indicating a resource block number when assigned, and so on.

The instantiated control channel decoding unit 88 decodes the instantiated control channel contained in the received signal. A particular control channel contains information about data modulation, channel coding rate, and HARQ of a common data channel.

Data channel decoding module 89 decodes a common data channel contained in a received signal based on information extracted from a particularized control channel. In accordance with the decoding result of the base station, acknowledgment (ACK) or negative acknowledgment (NACK) can be reported.

FIG. 8B shows an incomplete block diagram of a mobile terminal similar to the terminal of FIG. 8A, however, FIG. 8B differs from FIG. 8A in that each part of the control information is shown explicitly. The same reference signs indicate the same elements in figa and figv. In the figure, “restoration (reverse mapping) in a resource block” means retrieving information that is mapped in a limited manner to one or more resource blocks assigned to a particular communication terminal. “Recovery outside the resource block” means the allocation of information that is mapped to the entire frequency block containing many resource blocks.

On figs shows the elements related to the receiving module figa. Although not essential to the present invention, in the present embodiment, antenna diversity reception is performed using two antennas. The downstream signals received by the two antennas are supplied to the (81, 82) RF (radio frequency) reception circuit, respectively, the guard interval (cyclic prefix) is removed (83), and the fast Fourier transform is performed (84). The signals received by each antenna are combined by a diversity antenna combining module. After combining, a signal is supplied to each decoding module shown in FIG. 8A or the separation module shown in FIG. 8B.

Fig. 9 is a flowchart showing an example of operation in accordance with an embodiment of the present invention. As an example, it is believed that a user having a mobile terminal UE1, which can communicate using the 10 MHz frequency band, enters a cell or sector in which communication is carried out using the 20 MHz frequency band. It is believed that the minimum frequency band of the communication system is 5 MHz, and the entire frequency band is divided into four frequency blocks 1-4, as shown in figure 2.

In step S11, the terminal UE1 receives the broadcast channel from the base station and checks which frequency block this terminal can use. A broadcast channel may be transmitted using a 5 MHz frequency band including the center frequency of the entire 20 MHz band. Accordingly, any terminals in which the bandwidth that can be received is different can easily receive the broadcast channel. The broadcast channel allows a user who communicates using the 10 MHz frequency band to use a combination of two adjacent frequency blocks, such as frequency blocks (1, 2), (2, 3) or (3, 4). All may be authorized for use, or use may be limited to any of the combinations. As an example, it is believed that frequency blocks 2 and 3 are allowed for use.

In step S12, the terminal UE1 receives a downlink pilot channel for determining the quality of the received signal for frequency blocks 2 and 3. The determination is made for each of the plurality of resource blocks included in each frequency block, so that they are all reported to the base station as CQI channel status information.

In step S21, the base station performs frequency scheduling for each frequency block based on the channel status information CQI reported by the terminal UE1 and other terminals. The frequency block assignment control module (31 in FIG. 3A) checks and checks that the data channel addressed to UE1 is transmitted from the frequency block 2 or 3.

In step S22, the base station generates a control signal channel for each frequency block in accordance with scheduling information. The control signal channel includes an unspecified control channel and a specific control channel.

In step S23, the control channel and the common data channel are transmitted from the base station for each frequency block in accordance with scheduling information.

In step S13, the terminal UE1 receives the signal transmitted in the frequency blocks 2 and 3.

In step S14-0, the terminal UE1 recognizes the transmission format of the non-specific control channel from part 0 of the control channel received in the frequency blocks 2 and 3.

In step S14, the terminal extracts the non-specific control channel from the control channel received by the frequency unit 2, decodes it to extract scheduling information. Similarly, the terminal extracts the non-specific control channel from the control channel received in the frequency unit 3, decodes it to extract scheduling information. Any scheduling information includes information indicating whether a resource block is assigned to a common data channel addressed to terminal UE1, and whether it contains information indicating a resource block number when it is assigned, and the like. When no resource block is assigned to the common data channel addressed to this terminal, terminal UE1 returns to the idle state to wait for the control channel to be received. When a resource block is assigned to the common data channel addressed to this station, terminal UE1 allocates a specific control channel contained in the received signal and decodes it in step S15. A particular control channel includes information on modulation of data in a common data channel, channel coding rate, and HARQ.

In step S16, the terminal UE1 decodes the common data channel contained in the received signal based on information extracted from the instantiated control channel. In accordance with the decoding result of the base station, acknowledgment (ACK) or negative acknowledgment (NACK) may be reported. After that, similar actions are repeated.

OPTION 2

In the first embodiment, the control channel is classified into a specific control channel, which the terminal to which the resource block is assigned must decode and demodulate, and to other channels, and the specific control channel is limitedly mapped to the assigned resource block, and the other control channel is displayed in the entire band frequencies. Accordingly, for the control channel, transmission efficiency can be improved and quality can be improved. However, the present invention is not limited to such an example of a transmission method.

FIG. 7G shows an example of mapping data channels and control channels according to a second embodiment of the present invention. In the present embodiment, the base station shown in FIG. 3 is also used. In this case, with respect to the control channel, the elements shown in FIG. 4B are mainly used. In the present embodiment, the specific control information and the non-specific control information are not clearly distinguished, and they are transmitted using the entire frequency band area in several resource blocks. As shown in FIG. 4B, in the present embodiment, error correction coding is performed over the entire control channel for several users as a processing element. The user device (typically a mobile station) decodes and demodulates the control channel, determines whether the given station is assigned, and restores the data channel transmitted by the instantiated resource block according to the channel assignment information.

For example, assume that 10-bit control information is transmitted for each of the first to third user UE1, UE2, and UE3 to which resource blocks are assigned. All 30-bit control information for all three is error-corrected encoded as a processing element. When the code rate (R) is 1/2, 30 × 2 = 60 bits are generated and transmitted. On the other hand, unlike the present embodiment, the implementation of error correction coding and the transmission of each control information may be considered. In this case, the control information of 10 bits for one user is encoded with error correction, 10 × 2 = 20 bits are generated and they are prepared for all three (60 bits in total). The amount of control information transmitted becomes 60 bits anyway. However, according to the present embodiment, since the error correction coding processing element is three times longer than the other, this gives an advantage in terms of increasing the code gain (i.e., it becomes more difficult to cause an error). In addition, in the present embodiment, error detection bits (CRC bits and the like) are input to all 60 bits, but when error correction coding is performed for each user, error detection bits are input every 20 bits. Therefore, from the point of view of suppressing an increase in overhead due to detection bits, the present embodiment is preferred.

OPTION 3

FIG. 7H shows an example of mapping data channels and control channels according to a third embodiment of the present invention. In the present embodiment, the base station shown in FIG. 3 is also used, however, with regard to the control channel, the processing elements shown in FIG. 4C are mainly used. In the present embodiment, although the specific control information and the non-specific control information are not clearly distinguished, the control channel is limitedly mapped to the resource block assigned to the user who is to receive the control channel. For example, the control channel of the first user UE1 is mapped to the first and second resource blocks RB1 and RB2, the control channel of the second user UE2 is mapped to the third and fourth resource blocks RB3 and RB4, and the channel of the third user UE3 is mapped to the fifth resource block RB5. Error correction coding is carried out for each user. This is a difference from the second embodiment, in which the control channels from the first to the third users are error-corrected encoded and mapped to the entire resource blocks RB1-RB5.

In the present embodiment, the control channel and the data channel are limited to the same resource blocks, however, the resource blocks that are assigned to the mobile station are unknown to the mobile station before receiving the control channel. Therefore, it is necessary that each mobile station receives all resource blocks into which the control channel can be mapped so as to demodulate not only the control channel of the station, but also the control channels of other stations. In the example of FIG. 7H, the first user UE1 demodulates control channels mapped to all resource blocks RB1-RB5 in order to be able to know that the first and second resource blocks RB1 and RB2 are assigned to this station.

In the second embodiment, the transmit power of the base station is determined for the user in the worst conditions so that the user in the worst communication conditions can receive a control channel with the required quality. Therefore, the quality becomes redundant for users who are not in the worst communication conditions, so that the base station always needs to consume excess power. However, in the third embodiment, since processing such as error correction coding and the transmission frequency band are limited by the resource block for each user, transmission power can also be controlled for each user. Therefore, it becomes unnecessary for the base station to consume excess power. In addition, since the resource block assigned to the user has a good channel state, the control channel is transmitted with such a good channel state so that the quality of the control channel can be improved.

OPTION 4

FIG. 7I shows an example of a distribution of data channels and control channels according to a fourth embodiment of the present invention. In the present embodiment, the base station shown in FIG. 3 is also used, however, the control channel processing elements become those shown in FIG. 4C. In the present embodiment, although the specific control information and the non-specific control information are not clearly distinguished, the control channel is error-corrected encoded for each user so that the transmission power is determined similarly to the third embodiment. However, the control channel is not only mapped to resource blocks assigned to the user who is to receive the control channel, but also mapped to other resource blocks in a distributed manner. The control channel may also be transmitted in this manner.

Moreover, from the first to the fourth embodiments, when the control channel is mapped to several resource blocks in a distributed manner, it is not important to map the control channel to all resource blocks in a given frequency band. For example, a control channel can only be mapped to resource blocks with odd numbers RB1, RB3, ... in a given frequency band, or it can only be mapped to resource blocks with even numbers. The control channel may be limitedly mapped to any suitable resource blocks known between the base station and the mobile station. Accordingly, the search range used when a mobile station retrieves the destination information of a given station may be narrowed accordingly.

OPTION 5

As indicated above, in the second embodiment, the transmit power of the base station is determined for the user with the worst communication conditions so that the base station always consumes excess power. However, if the communication conditions of many users are equally good enough, such concerns can be overcome. Therefore, in communication conditions in which comparable quality can be achieved for several users, the method described in the second embodiment can be advantageous. From this point of view, in the fifth embodiment of the present invention, the user devices in the cell are appropriately grouped and the used frequency band is divided for each group.

7J is a schematic diagram for explaining a fifth embodiment of the present invention. In the example shown in the figure, three groups are provided according to the distance from the base station, wherein resource blocks RB1-RB3 are assigned to group 1, resource blocks RB4-RB6 are assigned to group 2, and resource blocks RB7-RB9 are assigned to group 3. The number of groups provided and the number of resource blocks is just an example, and any corresponding number can be used. After grouping, each of the various methods described in the first to fourth embodiments may be carried out. By grouping users and frequency bands, the difference in reception quality among users can be reduced. Accordingly, the problem (a problem causing concern in the second embodiment) that an excessive amount of transmit power is consumed in the base station due to the fact that the user in worse conditions can be effectively solved. In addition, in the third embodiment, when performing grouping as in the present embodiment, the transmission power of the control channel also becomes comparable in one group, so that there is an advantage from the point of view of stabilizing the operation of the transmitter of the base station and the like.

In the example shown in the figure, in order to simplify the explanation, three groups are provided in accordance with the distance from the base station. However, grouping can be performed not only based on distance, but also based on a channel quality indicator (CQI). CQI can be measured as any corresponding value that is known in the art, such as SIR (signal-to-interference ratio) and SINR (signal-to-total interference and noise ratio), etc.

OPTION 6

The non-specific control channel (including Part 0) is information necessary for all users, and the data channel is decoded based on the non-specific control channel. In this way, error determination coding (CRC) and channel coding are performed on the non-specific control channel. In a sixth embodiment of the present invention, specific examples of error detection coding and channel coding are explained. 4E corresponds to a configuration in which channel coding (including coding / spreading / modulating data modules 41, 42-A for data 41/42) of channel L1 / L2 control information (part 0) and channel L1 / L2 control information (parts 2a and 2b) is separately performed for each management information). The following describes alternative configurations of this option.

10A shows a case in which part 0 and parts 2a and 2b are encoded with error detection in general, wherein part 0 and parts 2a and 2b have undergone separate channel coding. Communication terminals UE1 and UE2 detect errors for part 0 and parts 2a and 2b in general and use the L1 / L2 control channel for a given communication terminal from parts 2a and 2b based on part 0.

Since the error detection code (CRC) may become larger than the control bits of part 0, in this case, the overhead of coding with error detection can be reduced.

10B shows a case in which part 0 and parts 2a and 2b are separately encoded with error detection and part 0 and parts 2a and 2b undergo separate channel coding. Although the overhead becomes larger compared with the case of FIG. 10A, there is an advantage in that when the error detection for part 0 fails, it becomes unnecessary to process for parts 2a and 2b.

On figs shows a case in which part 0 and parts 2A and 2b are encoded with error detection in whole and part 0 and parts 2a and 2b are channel-encoded as a whole. In this case, although the information of part 0 cannot be extracted until part 0 and parts 2a and 2b are decoded together, there is an advantage in that the efficiency of the channel code rate increases.

Although FIGS. 10A-10C describe error-coding and channel coding for part 0 and parts 2a and 2b, they can be similarly applied to non-specific control channels other than parts 2a and 2b.

OPTION 7

10D shows an example of a method for reducing the amount of information related to uplink channel data transmission. In step S1, a control channel L1 / L2 is transmitted from the base station. As indicated previously (in particular, as described with respect to FIG. 7F), several pieces of control information for several communication terminals are multiplexed and transmitted (assuming for convenience that the number of multiplexed users is N). Each communication terminal demodulates several L1 / L2 control channels addressed to this and other communication terminals. For example, it is believed that the control channel containing the UE-ID of this terminal is mapped to the Xth position among N. In this case, the user device demodulates at most N times in order to find the non-specific control channel addressed to this device displayed in X-th position, and finds out the contents of the destination (which resource block can be used for this terminal, etc.) of the terminal based on the destination information contained in it.

In step S2, the base station transmits (t = TTI1) an uplink packet using the assigned RB, for example. “T = TTI1” means time.

In step S3, the base station receives the uplink data channel D (t = TTI1), decodes it to determine the presence or absence of errors. The result of the determination is presented as ASK or NACK. The base station should report the result of the determination to the source of the communication terminal. The base station reports the determination result to the communication terminal using the L1 / L2 control channel. This determination result (transmission confirmation result) belongs to part 1 of the information related to the upstream data transmission, in accordance with the classification of FIG. 5A. Since the base station also receives uplink channels from various communication terminals, the base station reports transmission confirmation information to all communication terminals, respectively. Therefore, in order to distinguish these pieces of information with each other, in the downlink control channel L1 / L2, in each part 1 (ACK / NACK) of information related to upstream data, user identification information (ID) is input so that each terminal can accurately determine transmission acknowledgment information (ACK / NACK) for the uplink data channel that was previously transmitted by this terminal.

However, in the present embodiment, from the point of view of reducing the amount of control information, the downlink control channel L1 / L2 is transmitted without entering identification information of each piece of information of part 1 of each communication terminal. Instead, for each terminal, a correspondence relationship is maintained between the destination number X used in the distribution of part 2 information and part 1 information. For example, when the multiplexing method shown in FIG. 7F (1) is implemented, it is considered that for part 2 message information to the terminal UE1 the connection uses the destination number 3 (X = 3) (the third of the number of multiplexes N). In this case, the resource block of the uplink data channel is determined by demodulating the resource information of the assigned number 3 so that the uplink data channel is transmitted in the resource block. The information of part 1 for the uplink data channel is described in the resources of assigned number 3 in the downlink control channel L1 / L2 transmitted in t = TT1 + α, where α is the set time for returning the transmission confirmation information. In step S3, such a control channel L1 / L2 is transmitted to the communication terminal.

In step S4, each communication terminal reads part 1 information based on the destination number X and a predetermined period α to check whether it should retransmit data D (t = TTI1) that was transmitted in t = TTI1.

Accordingly, in the present embodiment, by maintaining the one-to-one correspondence relationship between the destination number that was used in step S1 and the destination number used in step S3, the base station does not need to determine that (ACK / NACK) of the information related part 1 to upstream data transmission, addressed to a particular communication terminal. Thus, according to the present method, the amount of L1 / L2 downlink control channel information generated in step S22 in FIG. 9 can be reduced. Assuming that resources for an uplink data channel are assigned to M communication terminals at time t = TTI1, destination number X is 1, ..., M, and the number of destination information (part 2) of information related to uplink data transmission and the number of destinations in that the transmission confirmation information (part 1) should be sent at the next time t = TTI + α, is also usually equal to M. Therefore, it is always possible to maintain the correspondence relation for destination number X one to one.

IMPLEMENTATION OPTION 8

10E shows an example of operation when frequency hopping is performed. The frequency band assigned to the communication system is 20 MHz and contains four frequency blocks, each of which has a minimum frequency bandwidth of 5 MHz. In the example shown in the figure, the communication system can accommodate 40 users who can communicate using the 5 MHz band, 20 users who can communicate using the 10 MHz band, and 10 users who can communicate using the band frequencies of 20 MHz.

A user who can communicate using the 20 MHz frequency band can always use all frequency blocks 1-4. However, among 40 users who can communicate only in the 5 MHz frequency band, users from the first to the tenth are allowed to use only frequency block 1 at time t, are allowed to use only frequency block 2 at time t + 1, and only frequency block is allowed 3 at time t + 2. Users from the eleventh to the twentieth are allowed to use only frequency blocks 2, 3, and 4 at times t, t + 1, and t + 2, respectively. Users from the twenty-first to the thirtieth are allowed to use only frequency blocks 3, 4 and 1 at time t, t + 1 and t + 2. Users from the thirty-first to the fortieth are allowed to use only frequency blocks 4, 1, and 2 at times t, t + 1, and t + 2. In addition, among the 20 users who can communicate only in the 10 MHz frequency band, users from the first to the tenth are allowed to use only frequency blocks 1 and 2 at time t, and only frequency blocks 3 and 4 are allowed to use at time t + 1 and only frequency blocks 1 and 2 are allowed to be used at time t + 2. Users from the eleventh to the twentieth are allowed to use only frequency blocks 3 and 4, 1 and 2, and 3 and 4 at times t, t + 1 and t + 2, respectively.

Such a frequency hopping pattern is previously communicated to the user by a broadcast channel or other methods. In this case, some patterns are predetermined as frequency hopping patterns, and the pattern number indicating which pattern among the patterns is used is communicated to the user, so that the frequency hopping pattern can be communicated to the user by a small number of bits. When there are several selections of used frequency blocks, like the present embodiment, it is desirable to change the used frequency block after starting communication in terms of equalizing communication quality among users and among frequency blocks. For example, if frequency hopping is not performed as in the present embodiment, a particular user should always communicate in poor conditions, when the difference between the best and worst communication qualities among the frequency blocks is large. When performing frequency tuning, although communication quality is poor at some time, it can be expected that it becomes good at another time.

In the example shown in the figure, various different frequency hopping patterns may be used, although a frequency hopping pattern is shown in which 5 MHz and 10 MHz frequency blocks are shifted to the right side one after the other. This is because even if any frequency hopping pattern is applied, it is only necessary that the pattern is known on the transmitting side and the receiving side.

OPTION 9

In a ninth embodiment of the present invention, the following describes a method for transmitting a call channel in addition to a control signaling channel.

11 shows a block diagram (left side) of an example of operation and a frequency band (right side) of an embodiment of the present invention. In step S1, a broadcast channel is transmitted to the users connected to the base station by the base station. As shown in FIG. 11 (1), a broadcast channel is transmitted using a minimum frequency band including the center frequency of the entire frequency band. The broadcast information reported by the broadcast channel contains the corresponding relationship between the frequency bands that the user can receive and the frequency blocks used.

In step S2, the user (UE1, for example) enters the standby state of a specific frequency block (for example, frequency block 1). In this case, the user UE1 adjusts the frequency band of the received signal so that it can receive the signal of the frequency unit 1, which is allowed for use. In the present embodiment, using the frequency block 1, not only a control signal channel is transmitted to the user UE1, but also a call channel for the user UE1. When it is determined that the user UE1 is called by the call channel, the circuit proceeds to step S3.

In step S3, according to the scheduling information, using the determined frequency block, a data channel is received. After that, the user UE1 again returns to the idle state.

12 shows a block diagram (left side) of another example of operation and a frequency band (right side) of an embodiment of the present invention. In step S1, like the example described above, the broadcast channel is transmitted to the users connected to the base station and the broadcast channel is transmitted using the minimum frequency band including the center frequency of the entire frequency band (Fig. 12 (1)). Like the example in FIG. 11, it is believed that the frequency block used is frequency block 1.

In step S2, the user UE1 enters the standby state. The difference from the top example is that the user UE1 does not adjust the frequency band of the received signal at this time. Therefore, the user UE1 expects a call channel using the same frequency band as for receiving a broadcast channel (FIG. 12 (2)).

In step S3, after determining the call channel, the terminal proceeds to the frequency block 1, which is assigned to this station, and receives the control signal channel for communication according to the scheduling information (Fig. 12 (3)). After that, the user UE1 again returns to the idle state.

In the example of FIG. 11, the terminal quickly transitions to the frequency unit 1 for a standby time. However, in the example shown in FIG. 12, the terminal does not go at this time, but goes to the frequency block 1 after the call of the given terminal is determined. In the first of two methods, each of the different users is waiting for a signal using the frequency block assigned to each user. On the other hand, in the latter method, each user expects a signal using the same frequency band. Therefore, the first method may be preferred over the latter in that frequency resources can be used uniformly. On the other hand, the search for an adjacent cell to verify the need for transition is carried out using the minimum frequency band in the center of the entire frequency band. Thus, from the point of view of reducing the number of adjustments to the frequency of the terminal, it is desirable to match the frequency band when using the waiting frequency band for cell search, similar to the example shown in FIG.

OPTIONAL IMPLEMENTATION 10

It is desirable to adapt the connection in terms of improving the quality of the received signal of the control channel. In a tenth embodiment of the present invention, transmission power control (TPC) and adaptive modulation and coding (AMC) are used as a method for adapting a connection. 13 shows a method by which transmit power is controlled, and its purpose is to obtain the desired quality at the receiving side by controlling the transmit power of the downlink. More specifically, since it is anticipated that the channel state of user 1 far from the base station is poor, the downlink channel is transmitted using high transmit power. In contrast, it is expected that for user 2, near the base station, the channel condition is good. In this case, if the transmission power of the downstream channel to user 2 is large, the received signal quality for user 2 may be good, but the interference for other users may become large. Since the channel condition for user 2 is good, the required quality can be ensured even if the transmit power is small. Therefore, in this case, the downlink is transmitted with a relatively low transmit power. When only transmission power is controlled, the modulation scheme and the channel coding scheme are kept constant, and a combination known for the transmitting side and for the receiving side is used. Therefore, there is no need to separately report the modulation scheme, etc. for channel demodulation in transmit power control.

Fig. 14 shows a method by which adaptive modulation and coding are controlled and in which it is planned to achieve the required quality at the receiving side by adaptively changing both or one of the modulation scheme and the coding scheme in accordance with good or bad channel condition. More specifically, if the transmit power of the base station is constant since it is predicted that the state of the user channel 1 remote from the base station is poor, the number of multi-level modulation levels is set low and / or the code rate is set low. In the example shown in the figure, QPSK is used as the modulation scheme for user 1, and 2-bit information is transmitted per character. On the other hand, it is predicted that the state of user channel 2 adjacent to the base station is good, the number of multi-level modulation levels is set large, and / or the code rate is set high. In the example shown in the figure, 16QAM is used as the modulation scheme for user 2, and 4-bit information is transmitted per character. Accordingly, the required quality for a user with a poor channel condition is achieved by improving reliability, and for a user with a good channel condition while maintaining the desired channel quality, throughput can be improved. In the management of adaptive modulation and coding during demodulation of the received channel, information is needed on the modulation scheme implemented in the channel, the coding scheme, the number of characters, etc. Thus, it is necessary that the information is communicated to the receiving side in some way. In addition, since the number of bits that can be transmitted per character is different according to the good or bad state of the channel, information can be transmitted by a small number of characters when the state of the channel is good, but when the state is not good, a large number of characters are needed.

In a tenth embodiment of the present invention, transmission power control is performed for an unspecified control channel to be decoded by non-specific users, and one or both of the transmission power control and adaptive modulation and coding control is performed for a specific control channel that is decoded by a specific user to whom the frequency block is assigned . In particular, the following three methods may be considered.

(1) TRS-TRS

In the first method, transmission power control is for a non-specific control channel, and only transmission power is controlled for a particular channel. Since the modulation scheme and similar parameters are fixed in the transmission power control, it can be demodulated with appropriate channel reception without prior notice of the modulation scheme and similar parameters. Since the non-specific control channel is distributed across all frequency blocks, the non-specific control channel is transmitted using the same transmit power over the entire frequency range. On the other hand, a specific control channel for a user occupies only a specific resource block for a user. Therefore, the transmit power of a particular control channel can be individually adjusted so that the quality of the received signal becomes good for each user to whom a resource block is assigned. For example, in the example shown in FIGS. 7A and 7B, a non-specific control channel may be transmitted using transmit power P ₀ , a specific user control channel 1 (UE1) may be transmitted using transmit power P ₁ corresponding to user 1, a specific user control channel 2 (UE2) may be transmitted using transmission power P _2, corresponding to user 2, and user 3 concretized (UE3) control channel may be transmitted using power P ₃ n, edachi corresponding to the user 3. In this case, the joint portion of the data channel may be transmitted with the same or different transmission power P _D.

As indicated above, the non-specific control channel must be decoded by all non-specific users. However, the main purpose of transmitting the control channel is to report that there is data to receive, and to report scheduling information, etc. a user who is actually assigned a resource block. Therefore, the transmit power during transmission of the non-specific control channel can be adjusted so that the reception quality is satisfactory to the user to whom the resource block is assigned. For example, in the examples shown in FIGS. 7A and 7B, when all users 1, 2, and 3 are located adjacent to the base station, the transmit power P ₀ of the non-specific control channel may be set relatively small. In this case, users other than users 1, 2, and 3 located on the edge of the cell, for example, may not be able to decode the non-specific control channel correctly. However, since a resource block is not assigned to users, there is actually no harm.

(2) TRS-AMS

In the second method, transmission power is controlled for the non-specific control channel and only adaptive modulation and coding are controlled for the specific control channel. When the AMC control is carried out, it is usually necessary that the modulation scheme, etc. reported in advance. In the present method, information such as a modulation scheme and the like is included in the non-specific control channel. Therefore, each user first receives the non-specific control channel, decodes and demodulates it to determine the presence or absence of data addressed to this station. If data is available, in addition to extracting scheduling information, the user retrieves information about the modulation scheme, coding scheme and number of characters, and the like, which is applied to the particularized control channel. Then, the instantiated control channel is demodulated in accordance with the planning information and the information of the modulation scheme, etc., information about the modulation scheme, and the like is obtained. for a shared data channel, so that the shared data channel is demodulated.

The control channel does not need to be transmitted at such a high speed compared to the shared data channel. Therefore, when the AMC is controlled for the non-specific control channel, the total number of combinations of modulation schemes, etc. may be less than the total number of modulation schemes, etc. for a shared data channel. For example, as a combination of AMS for a non-specific control channel, a QPSK modulation scheme can be fixed, and the code rate can vary as 7/8, 3/4, 1/2 and 1/4.

According to the second method, the quality of the specific control channel can be made good by keeping the quality of the non-specific control channel equal or greater than the predefined level for all users. This is because the instantiated control channel is mapped to a resource block with a good channel condition for each instantiated communication terminal and the corresponding modulation scheme and / or coding scheme is used. In the control channel, when implementing adaptive modulation and coding control in the part of the particularized control channel, the reception quality of the part can be improved.

Moreover, the number of combinations of modulation schemes and channel code rates can be limited by a small number, so that each combination can be tried on the receiving side during demodulation. Accordingly, even if information about the modulation scheme and the like is not communicated in advance, the AMC can be controlled within certain limits.

(3) TRS-TRS / AMC

In the third method, transmission power control is performed for an unspecified control channel, and for a specific control channel, both transmission power control and adaptive modulation and coding control are implemented. As indicated above, when performing AMC control, it is necessary, as a general rule, that the modulation scheme, etc. reported in advance. In addition, it is desirable that the total number of combinations of modulation schemes and channel code rates be large in terms of maintaining the required quality, even when there are greatly varying fading. However, with a large total number, the processes for determining the modulation scheme, etc. become complex, and the amount of information needed for notification becomes large, so that the computational load and overhead become large. In the third method, transmit power control is used in addition to the AMC control so that the required quality is supported by both. Consequently, there is no need to compensate for all greatly changing fading only by AMC control. In particular, a modulation scheme or the like is selected that reaches a neighborhood of the required quality, so that the desired quality can be supported by adjusting the transmit power with the selected modulation scheme, etc. Therefore, the total number of combinations of modulation schemes and channel coding schemes may be limited to a small amount.

In any of the above methods, since only the power of the non-specific control channel is controlled for the non-specific control channel, the user can easily obtain control information while maintaining the required quality. Unlike AMC control, since the amount of information transmission in terms of one character does not change, the transmission can easily be carried out using a fixed format. Since the non-specific control channel is distributed over the entire area of frequency blocks or over several resource blocks, the effect of frequency diversity is great. Therefore, it is expected that the required quality is achieved sufficiently by simple control of the transmission power, such as that in which the average level is regulated over a long period. For example, the transmission format used for the non-specific control channel may be controlled at a low speed using the broadcast channel.

When the AMC control information (information for determining the modulation scheme, etc.) of the specific control channel is included in the non-specific control channel, the AMC control can be performed for the specific control channel. Thus, for a specific control channel, transmission efficiency and quality can be improved. Although the number of characters needed for the non-specific control channel is almost constant, the number of characters needed for the specific control channel varies according to the content of the AMC control and the number of antennas, etc. For example, assuming that the number of necessary symbols is N when the channel code rate is 1/2 and the number of antennas is 1, the number of necessary symbols increases to 4N when the channel code rate is 1/4 and the number of antennas is 2. Accordingly, although the number of necessary symbols for the control channel changes, the control channel can be transmitted in a simple fixed format, as shown in FIGS. 7A and 7B of the present embodiment. The content of the change in the number of characters is not contained in the non-specific control channel and is contained only in the specific control channel. Therefore, when changing the fill factor of the control channel and the shared data channel in a particular resource block, such a change in the number of symbols can be carried out in a flexible way.

As indicated above, although preferred embodiments of the present invention are described, the present invention is not limited to them and various variations and modifications may be made without departing from the scope of the present invention. Although for purposes of explanation, the present invention has been described with a division into some embodiments, a division into each embodiment is not essential to the present invention and, if necessary, two or more embodiments may be used.

This application claims priority on the basis of Japanese application No. 2006-10496 filed with the Japanese Patent Office on January 18, 2006, the entire contents of the Japanese application being incorporated herein by reference.

This application claims priority on the basis of Japanese application No. 2006-127987, filed in the patent office of Japan on May 1, 2006, and the entire contents of the Japanese application is incorporated here by reference.

This application claims priority on the basis of Japanese application No. 2006-272347, filed in the patent office of Japan on October 3, 2006, and the entire contents of the Japanese application is incorporated here by reference.

This application claims priority on the basis of Japanese application No. 2006-298312 filed with the Japanese Patent Office on November 1, 2006, the entire contents of the Japanese application being incorporated herein by reference.

Claims (46)

1. A transmitting device comprising a frequency scheduling module configured to assign at least one resource block to individual communication terminals, wherein the frequency band provided to the communication system comprises several frequency blocks, each of which contains several resource blocks; a first generating unit configured to form a data channel for a communication terminal to which at least one resource block has been designated as a frequency scheduling unit; a second generating module, configured to generate a specific control channel individually for each communication terminal to which at least one resource block is assigned as a frequency planning module; a third generation module, configured to generate an unspecified control channel common to communication terminals to which at least one resource block is assigned as a frequency planning module; a fourth generating module, configured to generate a broadcast channel containing broadcast information communicated to the communication terminal; a multiplexing module configured to accommodate a broadcast channel formed by the fourth generation module in a frequency block including a center frequency from among several frequency blocks contained in a frequency band provided to the communication system, and with the possibility of accommodating an unspecified control channel formed by the third formation module at least one specific control channel formed by the second formation module, and at least one the second data channel generated by the first generation module in several frequency blocks contained in the frequency band provided to the communication system; and a transmission module, configured to transmit the output of the multiplexing module. 2. The device according to claim 1, characterized in that the instantiated control channel formed by the second formation module contains information related to the data modulation scheme. 3. The device according to claim 1, characterized in that the instantiated control channel formed by the second formation module contains information related to the encoding scheme. 4. The device according to claim 1, characterized in that the instantiated control channel formed by the second formation module contains information related to the hybrid control of the retransmission. 5. The device according to any one of claims 1 to 4, characterized in that the multiplexing module temporarily multiplexes at least one data channel generated by the first generation module, with an unspecified control channel formed by the third generation module, and at least one specific channel control formed by the second formation module. 6. The device according to any one of claims 1 to 4, characterized in that the multiplexing module places the call channel like a data channel. 7. The device according to claim 5, characterized in that the multiplexing module places the call channel like a data channel. 8. A data transmission method comprising the following steps: at least one resource block is assigned to individual communication terminals, wherein the frequency band provided to the communication system contains several frequency blocks, each of which contains several resource blocks; forming a data channel for a communication terminal to which at least one resource block is assigned; formulate a specific control channel individually for each communication terminal to which at least one resource block is assigned; form an unspecified control channel common to communication terminals to which at least one resource block is assigned; forming a broadcast channel containing broadcast information communicated to the communication terminal; placing a broadcast channel in a frequency block including a center frequency from among several frequency blocks contained in a frequency band provided to a communication system, and placing an unspecified control channel, at least one specific control channel and at least one data channel in several frequency blocks contained in the frequency band provided to the communication system; and transmitting the output signal obtained in the multiplexing step. 9. The method according to claim 8, characterized in that the instantiated control channel formed at the step of forming the instantiated control channel contains information related to the data modulation scheme. 10. The method according to claim 8, characterized in that the instantiated control channel generated at the step of forming the instantiated control channel contains information related to the encoding scheme. 11. The method according to claim 8, characterized in that the instantiated control channel formed at the step of forming the instantiated control channel contains information related to the hybrid control of the retransmission. 12. The method according to any one of claims 8 to 11, characterized in that at the placement step, temporary multiplexing of at least one data channel with an unspecified control channel and at least one specific control channel is performed. 13. The method according to any one of claims 8 to 11, characterized in that at the placement step, the call channel is placed like a data channel. 14. The method according to p. 12, characterized in that at the placement step, the call channel is placed like a data channel. 15. A transmitting device comprising a frequency scheduling module configured to assign at least one resource block to individual communication terminals, wherein the frequency band provided to the communication system comprises several frequency blocks, each of which contains several resource blocks; a first generating unit configured to form a data channel for a communication terminal to which at least one resource block has been designated as a frequency scheduling unit; a second generating module, configured to generate a specific control channel individually for each communication terminal to which at least one resource block is assigned as a frequency planning module; a third generation module, configured to generate an unspecified control channel common to communication terminals to which at least one resource block is assigned as a frequency planning module; a fourth generating module, configured to generate a broadcast channel containing broadcast information communicated to the communication terminal; a multiplexing module configured to accommodate a broadcast channel formed by the fourth generation module in a frequency block including a center frequency from among several frequency blocks contained in a frequency band provided to the communication system, and with the possibility of accommodating an unspecified control channel formed by the third formation module at least one specific control channel formed by the second formation module, and at least one the second data channel generated by the first generation module in several frequency blocks contained in the frequency band provided to the communication system; and a transmission module, configured to transmit the output of the multiplexing module, wherein the multiplexing module is configured to use a localized circuit for assigning continuously located resource blocks for the data channel, and a distributed circuit in which the resource blocks corresponding to multiple frequency components. 16. The device according to p. 15, characterized in that the instantiated control channel formed by the second formation module contains information related to the data modulation scheme. 17. The device according to p. 15, characterized in that the instantiated control channel formed by the second formation module contains information related to the encoding scheme. 18. The device according to p. 15, characterized in that the instantiated control channel formed by the second formation module contains information related to hybrid control retransmission. 19. The device according to p. 15, characterized in that the instantiated control channel formed by the second formation module contains precoding information for use in a multi-input and output (MIMO) circuit. 20. The device according to any one of paragraphs.15-19, characterized in that the multiplexing module temporarily multiplexes at least one data channel generated by the first generation module, with an unspecified control channel formed by the third generation module, and at least one specific channel control formed by the second formation module. 21. The device according to any one of paragraphs.15-19, characterized in that the multiplexing module places the call channel like a data channel. 22. The device according to claim 20, characterized in that the multiplexing module places the call channel like a data channel. 23. A data transmission method, comprising the following steps: at least one resource block is assigned to individual communication terminals, wherein the frequency band provided to the communication system contains several frequency blocks, each of which contains several resource blocks; forming a data channel for a communication terminal to which at least one resource block is assigned; formulate a specific control channel individually for each communication terminal to which at least one resource block is assigned; form an unspecified control channel common to communication terminals to which at least one resource block is assigned; forming a broadcast channel containing broadcast information communicated to the communication terminal; placing a broadcast channel in a frequency block including a center frequency from among several frequency blocks contained in a frequency band provided to a communication system, and placing an unspecified control channel, at least one specific control channel and at least one data channel in several frequency blocks contained in the frequency band provided to the communication system; and transmitting the output signal obtained in the multiplexing step, while in the multiplexing step, it is possible to use a localized circuit in which continuously located j resource blocks are assigned for the data channel and a distributed circuit in which resource blocks corresponding to several frequency components are assigned in an intermittent manner. 24. The method according to item 23, wherein the instantiated control channel generated at the step of forming the instantiated control channel, contains information related to the data modulation scheme. 25. The method according to item 23, wherein the specific control channel formed at the step of forming a specific control channel contains information related to the encoding scheme. 26. The method according to item 23, wherein the instantiated control channel formed at the step of forming the instantiated control channel, contains information related to the hybrid control of the retransmission. 27. The method according to item 23, wherein the instantiated control channel generated at the step of forming the instantiated control channel, contains precoding information for use in a circuit with multiple inputs and outputs (MIMO). 28. The method according to any one of paragraphs.23-27, characterized in that at the placement step, temporary multiplexing of at least one data channel with an unspecified control channel and at least one specific control channel is performed. 29. The method according to any one of paragraphs.23-27, characterized in that at the placement step, the call channel is placed like a data channel. 30. The method according to p. 28, characterized in that at the placement step, the call channel is placed like a data channel. 31. A transmitting device comprising a frequency scheduling module configured to assign at least one resource block to individual communication terminals, wherein the frequency band provided to the communication system comprises several frequency blocks, each of which contains several resource blocks;
a first generating unit configured to form a data channel for a communication terminal to which at least one resource block has been designated as a frequency scheduling unit;
a second generating module, configured to generate a specific control channel individually for each communication terminal to which at least one resource block is assigned as a frequency planning module;
a third generation module, configured to generate an unspecified control channel common to communication terminals to which at least one resource block is assigned as a frequency planning module;
a fourth generating module, configured to generate a broadcast channel containing broadcast information communicated to the communication terminal; a multiplexing module configured to accommodate a broadcast channel formed by the fourth generation module in a frequency block including a center frequency from among several frequency blocks contained in a frequency band provided by the communication system and with the possibility of accommodating an unspecified control channel formed by the third formation module at least one specific control channel formed by the second formation module, and at least one the second data channel generated by the first generation module in several frequency blocks contained in the frequency band provided to the communication system; and a transmission module, configured to transmit the output signal of the multiplexing module, the number of characters in the part that contains at least one specific control channel formed by the second formation module is variable, and the non-specific control channel formed by the third generation module contains information related to the number of characters in the part that contains at least one specific control channel formed by the second module Ania. 32. The device according to p. 31, characterized in that the instantiated control channel formed by the second formation module contains information related to the data modulation scheme. 33. The device according to p, characterized in that the instantiated control channel generated by the second formation module contains information related to the encoding scheme. 34. The device according to p, characterized in that the instantiated control channel generated by the second formation module contains information related to the hybrid control of the retransmission. 35. The device according to p. 31, characterized in that the instantiated control channel generated by the second module formation, contains precoding information for use in a circuit with multiple inputs and outputs (MIMO). 36. The device according to any one of paragraphs.31-35, characterized in that the multiplexing module temporarily multiplexes at least one data channel generated by the first generation module, with an unspecified control channel formed by the third generation module, and at least one specific channel control formed by the second formation module. 37. The device according to any one of paragraphs.31-35, characterized in that the multiplexing module places the call channel like a data channel. 38. The device according to clause 36, wherein the multiplexing module places the call channel like a data channel. 39. A data transfer method comprising the following steps:
at least one resource block is assigned to individual communication terminals, wherein the frequency band provided to the communication system comprises several frequency blocks, each of which contains several resource blocks;
forming a data channel for a communication terminal to which at least one resource block is assigned;
formulate a specific control channel individually for each communication terminal to which at least one resource block is assigned;
form an unspecified control channel common to communication terminals to which at least one resource block is assigned; forming a broadcast channel containing broadcast information communicated to the communication terminal;
placing a broadcast channel in a frequency block including a center frequency from among several frequency blocks contained in a frequency band provided to a communication system, and placing an unspecified control channel, at least one specific control channel and at least one data channel in several frequency blocks contained in the frequency band provided to the communication system; and transmitting the output signal obtained in the multiplexing step, wherein the number of characters in the part that contains at least one specific control channel formed in the step of forming the specific control channel is variable, and the non-specific control channel formed in the step of forming the non-specific control channel contains information related to the number of characters in that part that contains at least one specific control channel formed at the step of forming a specific control channel. 40. The method according to § 39, wherein the instantiated control channel generated at the step of forming the instantiated control channel contains information related to the data modulation scheme. 41. The method according to § 39, wherein the instantiated control channel formed at the step of forming the instantiated control channel contains information related to the encoding scheme. 42. The method according to § 39, wherein the instantiated control channel generated at the step of forming the instantiated control channel contains information related to the hybrid control of the retransmission. 43. The method according to § 39, wherein the instantiated control channel formed at the step of forming the instantiated control channel contains precoding information for use in a multi-input and output (MIMO) circuit. 44. The method according to any one of paragraphs 39-43, characterized in that at the placement step, temporary multiplexing of at least one data channel with an unspecified control channel and at least one specific control channel is performed. 45. The method according to any of paragraphs 39-43, characterized in that at the placement step, the call channel is placed like a data channel. 46. The method according to item 44, wherein the step of placing the call channel is placed like a data channel.

Images