RU2428815C2 - Transmitter, receiver and method of communication - Google Patents

Abstract

FIELD: information technologies.

SUBSTANCE: transmitter includes a module of system information generation, arranged with the possibility of multiplexing information on a system frequency band in a broadcasting channel of an element from the system information, which is required to search for a cell, and multiplexing another element of the system information in the channel that differs from the broadcasting channel, and it differs from the element of the system information on the system frequency band, which is multiplexed in the broadcasting channel; and a module of transmission arranged with the possibility to transmit a broadcasting channel and a channel that differs from the broadcasting channel, at the same time the element of information on the system frequency band indicates the frequency band of the system in a basic station that comprises the transmitter.

EFFECT: reduced volume of information processing during cell searching, less time required for cell searching.

51 cl, 16 dwg

Description

FIELD OF THE INVENTION

The present invention relates to the field of transmitters, receivers and communication methods for carrying out communication according to the OFDM scheme.

State of the art

In multi-carrier transmission schemes, such as MC-CDMA (Multi Carrier Code Division Multiple Access) or OFDM (Orthogonal Frequency Division Multiplexing) or modulated orthogonal frequency division) modulation schemes, the information signal is modulated on the transmitter side on several subcarriers, and guard intervals are inserted into the transmitted signals in order to reduce waveform distortions caused by delayed waves arriving along different paths.

As one of the methods for detecting FFT temporal parameters (fast Fourier transform, fast Fourier transform) in multi-carrier transmission schemes based on the OFDM modulation scheme, a known method for detecting FFT temporal parameters by correlating guard intervals inserted for each symbol is used. In addition, there is a method for detecting FFT time parameters by transmitting the same signal twice as a serial signal used as a time parameter detection signal and determining a correlation between two symbols on the receiver side.

In addition, a transmitter has been proposed that multiplexes and transmits synchronization signals with a specific time distribution described in Patent Document 1 below. The synchronization signals in this transmitter are transmitted as pulses on all subcarriers. For example, if the start time of a single spreading (scrambling) code template is set to coincide with the transmission time of the synchronization signal in the transmitter, then the synchronization signal is transmitted twice during the cycle time t of a single spreading code template.

Hereinafter, references are made to the following documents.

Patent Document 1: JP 2003-152681

Non-Patent Document 1: S.M. Alamouti, "A simple transmit diversity technique for wireless communications", IEEE J. Select. Areas Commun., Vol. 16, no. 8, pp. 1451-1458, October 1998

Non-Patent Document 2: K. Suto, T. Ohtsuki, "Performance evaluation of space-time-frequency block codes over frequency selective fading channels", IEEE VTC2002-Fall, pp. 1466-1470, Sept. 2002

Non-Patent Document 3: 3GPP TS25.211 Physical channels and mapping of transport channels onto physical channels (FDD)

Non-Patent Document 4: CDD (Cyclic Delay Diversity): Armin Dammann and Stefan Kaiser, "Standard conformable antenna diversity techniques for OFDM and its application to the DVB-T system", GLOBECOM 2001, pp.3100-3105, November 2001

Non-Patent Document 5: D. Chase, "Code combining - a maximum-likelihood decoding approach for combining an arbitrary number of noisy packets", IEEE Trans. Commun., Vol. 33, no.5, pp. 385-393, May 1985

Non-Patent Document 6: D. Rowitch and L. Milstein, "On the performance of Hybrid FEC / ARQ Systems Using Rate Compatible Punctured Turbo (RCPT) Codes", IEEE Trans, on Commun., Vol. 48, no.6, June 2000

The above technology has several disadvantages described below.

In the above transmitter in broadcast channels (BCH), various elements of system information are transmitted, such as information related to the configuration of the downlink control channel, information about adjacent cells and other control information. In general, system information transmitted over the BCH is always transmitted with a constant period, which leads to unproductive consumption of resources, and, as a result, the transmission speed on the BCH is low. As a result, receiving broadcast channels to obtain system information takes a longer time, which leads to a longer cell search time, i.e. the time required to detect a cell and obtain cell system information by mobile stations.

In addition, a large amount of processing is required to search for cells in mobile stations.

Finally, a significant amount of system information transmitted over the BCH can lead to increased overhead of resources in the system.

Disclosure of invention

Thus, the present invention addresses the aforementioned problems and provides a transmitter, a receiver, and a communication method for reducing the processing amount of a cell search, cell search time, and system overhead.

In order to eliminate the aforementioned problems, the present invention proposes a transmitter including a system information generating module configured to generate system information; a multiplexing module configured to multiplex in the broadcast channel a system information element from system information necessary for cell search, and multiplex in a channel other than a broadcast channel, a system information element from system information other than a system information element necessary for cell search; and a transmission module, configured to transmit the broadcast channel and a channel other than the broadcast channel.

By using said transmitter, cell search time in mobile stations can be reduced. In this case, the cell search time includes the reception time of the broadcast channel. In addition, it is possible to reduce the amount of processing when searching for a cell.

Further, the present invention provides a receiver including a broadcast channel receiving module, configured to receive a broadcast channel transmitted by a base station; an extraction module configured to search for a cell based on a broadcast channel and extract information indicating a channel other than a broadcast channel and used to transmit a system information element other than a system information element that is needed to search for a cell; and a receiving module, configured to receive a channel other than a broadcast channel based on information indicating a channel other than a broadcast channel, where the channel serves to transmit a system information element other than a system information element necessary for cell search.

By using said receiver, cell search time can be reduced. In this case, the cell search time includes the reception time of the broadcast channel. In addition, it is possible to reduce the amount of processing when searching for a cell.

Further, the present invention proposes a communication method, comprising the following steps: generating system information; multiplexing in a broadcast channel an element of system information from system information necessary for cell search; and broadcast channel transmission.

By using this communication method, cell search time in mobile stations can be reduced. In this case, the cell search time includes the reception time of the broadcast channel. In addition, it is possible to reduce the amount of processing performed when searching for a cell.

According to embodiments of the present invention, there is provided a transmitter, a receiver, and a communication method for reducing the amount of processing to perform when searching for a cell, the time of searching for a cell, and system overhead.

Brief Description of the Drawings

Figure 1 shows an incomplete block diagram of a transmitter according to one embodiment of the present invention;

2 is a diagram illustrating a transmission band of a broadcast channel and a synchronization channel;

3A is an incomplete block diagram of a transmitter according to one embodiment of the present invention;

3B is an incomplete block diagram of a transmitter according to one embodiment of the present invention;

Fig. 4 is a diagram illustrating transmission frequency bands of common data channels over which a call indicator channel, a call channel, and call information are transmitted;

5A is a diagram illustrating soft combining of sectors in one base station;

5B is a diagram illustrating soft combining of sectors in one base station;

6 is a diagram illustrating an example of the operation of a base station including a transmitter according to one embodiment of the present invention;

7A is a diagram illustrating radio resource blocks allocated to call channels;

Fig. 7B is a diagram illustrating a transmission method used in a transmitter according to one embodiment of the present invention;

on figa shows an incomplete block diagram of a receiver according to one of the embodiments of the present invention;

on figv shows an incomplete block diagram of a receiver according to one of the embodiments of the present invention;

Fig.9 is a block diagram illustrating an example of a receiver in accordance with one embodiment of the present invention;

10 is a flowchart illustrating a time distribution of a user identifier assignment process;

11 is a flowchart illustrating a time distribution of a user identifier assignment process;

12 is a flowchart illustrating a time distribution of a user identifier assignment process;

13 is an incomplete block diagram of a transmitter according to one embodiment of the present invention;

14 is a diagram illustrating a transmission method used in a transmitter according to one embodiment of the present invention;

15 is an incomplete block diagram of a transmitter according to one embodiment of the present invention;

Fig.16 shows an incomplete block diagram of a receiver according to one embodiment of the present invention.

The following notation is used in the drawings.

10: transmitter

20: receiver

The implementation of the invention

Embodiments of the present invention will now be described with reference to the drawings. Objects having the same functions in all the drawings illustrating embodiments have the same reference signs, and descriptions thereof are not repeated.

A radio communication system according to an embodiment of the present invention is described. In this embodiment, the radio communication system includes a base station and a mobile station. The base station includes a transmitter 10, the mobile station includes a receiver 20.

A transmitter 10 according to this embodiment is described below with reference to FIG.

The transmitter 10 transmits the common data channels (shared data channels) and broadcast channels (broadcast channels). Broadcast channels are used by a mobile station containing a receiver 20 to perform a cell search. As used herein, the term “cell search” means some of the steps that are taken before a cell is detected and minimum system information is obtained. Further, a mobile station comprising a receiver 20 obtains various elements of system information by receiving common data channels. Then, the mobile station containing the receiver 20 receives paging information by receiving paging channels or common data channels.

At the base station, a transmitter 10 is installed that transmits radio signals. The transmitter 10 includes a generator 100 broadcast channels and common data channels.

In the generator 100 broadcast channels and common data channels can perform a number of operations, described below.

The necessary minimum system information coming from the system information generation module 101 ₁ , such as information indicating the system bandwidth of a given base station, and information indicating common data channels through which system information elements other than the required minimum system information, including one or more information elements, for example, information elements indicating the frequency, time, cell identifier, SFN (System Frame Number) the network’s core (operator information) and the number of transmit antennas are encoded in the transmission path encoder 102 ₁ and then modulated in the modulation module 103 ₁ .

In addition, system information coming from the system information generation module 101 ₂ and not related to the necessary minimum system information, i.e. various information elements related to mobile stations, such as the values of various timers (cell selection timers), values of various parameters (reception level notification cycle, initial transmit power, etc.), location information of a registration area, cell selection information (threshold cell selection for cell selection, such as reception level information), uplink interference level, location information (latitude and longitude information, etc.), local cell channel configuration information (call channels, in addition to BCH and control channels L1 / L2 (Level 1 / Level 2, level 1 / level 2)), information about the core network, measurement information from user equipment (UE, user equipment), configuration information of the downlink control channel, information about adjacent cells (cell identifiers, system bandwidth, BCH channel bandwidth, number of transmitting antennas, time distribution information (time difference between base stations), transmit power and number of sectors of neighboring cells) and various setting information elements encoded in encoder 102 ₂ paths per cottages and then modulated in the modulation unit 103 _2.

The paging indicator information and call information generated by the call information generating unit 116 based on the call or call signals from the networks are encoded in the transmission path encoder 102 ₃ and then modulated in the modulation module 103 ₃ .

System information, call indicator information, and call information that have passed modulation are multiplexed by the multiplexing module 104 in the broadcast channels and common data channels and undergo serial-parallel conversion performed by the serial-parallel conversion module 105 into N sequences of information symbols on the frequency axis. The converted N sequences of information symbols are distributed along the frequency axis.

Symbol sequences of N are multiplied in the frequency direction N by multiplication units 111 with spreading codes coming from a distribution code generator 110 controlled by a control unit 115; further, the multiplied symbol sequences are transmitted to the combining unit 112. The combining unit 112 multiplexes the symbol sequences of the number N multiplied with spreading codes in a specific subcarrier corresponding to a synchronization signal in N subcarriers.

Inverse fast Fourier transform (IFFT) module 113 converts N symbols to orthogonal signals on a plurality of carriers. Module cyclic prefix (cyclic prefix, CP) inserts CP into the signals on the set of carriers for each target Fourier time period. Then, the transmitter 10 generates radio signals from signals on a plurality of carriers coming from the CP adding unit 114, and transmits them to the air.

The following describes a series of steps for generating broadcast channels and common data channels in a generator 100 of broadcast channels and common data channels.

System information generation module 101 ₁ generates the minimum system information that needs to be transmitted in broadcast channels. System information generation module 101 ₁ may generate system information necessary for cell search and including at least one information element from information indicating a system frequency band of a given base station and information indicating common data channels for transmitting system information elements different from the required minimum system information, cell identifiers and the number of transmitting antennas.

In UTRA and UTRAN systems, which are an evolution of the 3GPP standard, the system bandwidth can be between 1.25 MHz and 20 MHz. In this embodiment, the transmitter 10 always transmits broadcast channels using 1.25 MHz, or optionally broadcasts them using either 1.25 MHz or 5 MHz.

If the transmission frequency band of the broadcast channels is predetermined in a similar manner, the mobile stations can receive the broadcast channels even before the system frequency band is known, and can recognize the system frequency band using broadcast channel reception.

The broadcast channel for the transmitter 10 of the present embodiment is defined as a physical channel predetermined in the system and independent of the common data channel.

In addition, as shown in FIG. 2, mobile stations can receive broadcast channels immediately after searching for a cell without changing the center frequency, by transmitting broadcast channels at the same center frequency as the synchronization channels. As a result, the necessary minimum system information can be obtained in a short period of time. In addition, reception operations in mobile stations can be simplified by setting the center frequency of the broadcast channels in the center of the system bandwidth.

In addition, broadcast channels are transmitted in a smaller frequency band compared to the minimum frequency band that all mobile stations must receive, which allows broadcast channels to be received by all mobile stations.

System information generation module 101 ₂ generates system information elements other than the required minimum system information. For example, the system information generating module 101 ₂ generates various elements of system information, such as the configuration of the downlink control channel, information about adjacent cells (identifiers of adjacent cells, time distribution of transmission, etc.), various tuning information, information about the interference level in uplink channel, the configuration of the control channel of a given cell, such as information about the radio resources of the common data channels used to transmit system information, and information indicating the DRX period (discontinuous reception discrete reception).

The type and / or amount of system information may vary depending on specific operators and cells. If elements of system information other than the required minimum system information are transmitted in common data channels, as described above, then system information can be transmitted with great flexibility.

In this case, information is transmitted in the broadcast channel indicating how much of the common data channel is used to transmit system information, i.e. information that indicates the frequency and times of transmission of system information. As a result, the content of control information in the broadcast channel can be correspondingly increased. On the other hand, since mobile stations can receive a common data channel through which system information is transmitted immediately after receiving a broadcast channel, mobile stations can receive system information in a shorter period of time. In addition, since various elements of system information may be used for different cells, greater flexibility can be provided.

Further, information indicating the frequency and time of transmission of system information may be transmitted in the L1 / L2 control channels. Since the mobile station receives the common data channel through which system information is transmitted, after receiving the broadcast channel and further receiving the L1 / L2 control channels, receiving system information by the mobile station may take a longer time, while a smaller amount may be transmitted in the broadcast channel management information. In addition, various elements of system information may be used for different cells, thereby achieving greater flexibility.

Further, information indicating the frequency and time of transmission of system information can be determined in advance in the system. As a result, although flexibility is reduced due to the use of a fixed system, the mobile station can receive system information in a shorter period of time without increasing the amount of control information in the broadcast channel.

Finally, elements of system information transmitted in a common data channel and other than the required minimum system information transmitted in a broadcast channel can be divided into classes, and the transmission can occur so as to identify the classified system information, and what part of the common data channel those. frequency and time, used to transmit elements of classified system information.

For example, information blocks whose contents can change in a relatively short period of time, such as setting information, are separated from information blocks whose contents cannot change over time, such as information about adjacent cells, after which part identification is performed during the transmission, used to transmit relevant blocks of information.

Thus, only those parts that need to be received periodically can be realized at the mobile station. This allows you to reduce battery power consumption in the mobile station while waiting.

For example, system information generation module 101 ₂ generates tuning information, uplink interference level information, information indicating a control channel configuration of a given cell (such as radio resource information of common data channels through which system information is transmitted) as system information, system information adjacent cells (eg, neighboring cell identifiers, transmission times, etc.), and information indicating a discontinuous reception period; classifies these information elements and generates information indicating which parts of the common data channel are used to transmit these information elements.

The call information generating unit 116 generates call indicator information and call information based on the call or call signals coming from the networks.

In PDC (Personal Digital Cellular) or 3G systems, physical control channels are determined separately from the data channels through which call information and other control information are transmitted, and are used to transmit call information.

If the call information is transmitted via common data channels, then the definition of physical control channels for call information is not required, which allows the use of simpler radio frequency interfaces. As a result, it is possible to simplify the reception operations in the mobile stations and the transmission operations in the base stations. In addition, data in common data channels can be transmitted at different data rates, which increases call flexibility.

As shown below, when transmitting call information, common spreading codes can be used in sectors within the same base station, which allows soft-combining reception on the receiver side, and call channels can be determined separately from common data channels. Moreover, radio resource blocks for call channels, i.e. time and frequency can be fixed or variable. If variable parameters are used, information indicating the radio resource blocks for the call channels may be transmitted in the paging indicator channel or in the L1 / L2 control channels.

Further, PI (page indicator) information indicating the presence of a call may be transmitted via the L1 / L2 control channel or the broadcast channel. In this case, as shown in FIG. 3A, the call information that is generated by the call information generating unit 116 based on the call or call signal coming from the network is added by the adder 118 to the PI information generated by the L1 / L2 control information generating unit 117, after why the received information is transmitted to the transmission path encoding module 102 ₃ .

Further, a call indicator channel and a call channel or a common data channel serving to transmit call information are transmitted at the same center frequency as the transmission frequency of the broadcast channels. According to the present embodiment, reception operations in mobile stations can be simplified.

Further, reception operations in mobile stations can be simplified by transmitting a call indicator channel and a call channel or a common data channel for transmitting call information at the same center frequency as the center frequency of the system bandwidth, as shown in FIG. 4 .

Further, all mobile stations can receive call signals due to the fact that the call channel or the common data channel used to transmit the call information is transmitted with a narrower frequency band compared to the minimum frequency band that all mobile stations must receive.

Finally, reception operations in mobile stations can be simplified by using one block of radio resources or part thereof to transmit a call channel or a common data channel through which call information is transmitted, as shown in FIG. 4.

In 3G systems, a physical PICH control channel (Page Indicator Channel) is defined for transmitting PI information. In this case, the receiving operations in the mobile stations and the transmission operations in the base stations can be simplified by including the PI information function in the L1 / L2 control channels.

Further, the control signals of the common data channels are transmitted in the control channels L1 / L2, and the control signals of the common data channels used to transmit call information, or call channels, are transmitted to the PICH. As a result, matching radio resource blocks for L1 / L2 control channels and radio resources for PICH is not required.

If the mobile station detects the presence of a call based on the PI information, then the mobile station receives information indicating a common data channel through which the call information is transmitted.

In addition, as shown in FIG. 3B, a physical control channel dedicated to transmit PI information may be used to transmit PI information. In this case, PI information is transmitted in the PICH channel, while call information is transmitted in the call channel or the common data channel.

Mobile stations can receive PICH immediately after performing a cell search by positioning the PICH in the center of the system bandwidth.

If PI information is transmitted in the L1 / L2 control channels, then information indicating the radio resource blocks (time and frequency) of the common data channels serving to transmit call information to a mobile station receiving PI information is transmitted in these channels. In other words, in the information function of the PI control channels L1 / L2, a function for transmitting radio resource blocks for transmitting call information is added. In this case, the amount of control information in the L1 / L2 control channels increases accordingly, but flexibility can be increased.

Further, information indicating radio resource blocks for common data channels serving to transmit call information to a mobile station receiving PI information may be predetermined in the system. This allows you to increase the amount of control information for the control channels L1 / L2.

In addition, information indicating radio resource blocks for common data channels by which call information is transmitted to a mobile station receiving PI information can be transmitted as system information.

Mobile stations are notified of a call through the PI function based on the DRX cycle.

The base station can provide DRX cyclically by creating a variable DRX cycle.

With the lengthening of the notification cycle of a certain mobile station about the presence of a call by means of the PI function, the interval of discontinuous reception at the mobile station also becomes longer. This fact is an advantage in terms of saving battery power, but can lead to an increase in call delay. The variable DRX cycle allows for flexible operation.

In this case, the DRX cycle is transmitted in the system information transmitted in the common data channels, as described above. According to this embodiment, the DRX cycle can be transmitted without increasing the amount of information in the broadcast channels. In addition, the DRX cycle may be set different for individual cells.

Further, the transmitter 10 may transmit a DRX cycle in the BCH channels. In this case, the system information generating unit 101 ₁ generates information reflecting the DRX cycle. According to this embodiment, the amount of information in the broadcast channels may increase accordingly, however, the DRX cycle can be identified without receiving common data channels. In addition, the DRX cycle may be set different for individual cells.

In the case of transmitting call information, the transmission path encoding module 102 ₃ performs encoding at a predetermined and fixed code rate, and the modulation module 103 ₃ performs modulation in accordance with a predetermined and fixed modulation scheme.

When transmitting call information, the network side does not have any data on the location of the mobile stations, and therefore cannot receive the level of propagation loss. As a result, it is necessary to transmit call information under the assumption of the worst case, i.e. a case in which a mobile station is located at a cell boundary. In view of this, a modulation scheme and code rate can be used to provide call information at mobile stations located at the cell boundary.

With a fixed modulation scheme and code rate, it is not necessary to transfer the modulation scheme and code rate to the PI function, which leads to less control information for the PI function. In particular, a QPSK modulation scheme and a code rate of 1/3 or 1/2 can be applied.

The following describes some operations in the control unit 115.

In CDMA systems, in the case where several base stations transmit similar signals in several sectors, mobile stations located in the border area between adjacent sectors can receive similar signals from adjacent sectors. For example, mobile stations may receive signals coming from adjacent sectors, as shown in FIG. 5A. In this case, however, base stations must use a double amount of radio resources. On the other hand, signals coming from adjacent sectors to mobile stations interfere with each other, which leads to unjustified consumption of resources and inefficiency.

In OFDMA (orthogonal frequency division multiple access) systems, when sectors use common spreading codes and transmission times are synchronized, signals from adjacent sectors do not interfere and are combined when receiving signals from sectors (soft combining )

In the case of transmitting PI information in the L1 / L2 control channels, soft combining is applied only to the call information transmitted in the common data channels. In the L1 / L2 control channels, in addition to PI information, other signals are transmitted, so different spreading codes are used for different sectors. These spreading codes cannot be made the same. In particular, the control unit 115 provides the same spreading codes for call information transmitted in call channels or common data channels, as shown in FIG. 6, and controls to synchronize transmission times. For example, as shown in FIG. 5B, a base station transmits call information multiplied with common spreading codes from adjacent sectors at the same time by coordination between sector schedulers. According to this embodiment, the receiver side may receive combined call information.

Further, if PI information is transmitted on the PICH, and call information is transmitted on the call channels or common data channels, then soft combining is applied to the parts of the call information transmitted on the PICH and / or on the common data channels or call channels. In this case, the control unit 115 provides the same spreading code and transmission times in sectors for the call channel or common data channels in which the call information is multiplexed. In addition, the control unit 115 provides the same spreading code and transmission times in sectors for the call indicator channel in which the call indicator information is multiplexed.

In particular, the control unit 115 applies the same spreading codes to the PI information transmitted in the PICH and / or call information transmitted in the call channels or common code channels, and controls the timing of the transmission. For example, as shown in FIG. 5B, the base station transmits PI information and / or call information multiplied with common spreading codes from adjacent sectors at the same time by coordinating sector planners. According to this embodiment, the receiver side may receive combined PI information and / or call information.

According to this embodiment, the reception quality of the PICH and / or the call channel or the common data channel can be improved by softly combining sectors in one base station without performing complex operations on the side of the mobile station.

Further, the transmitter 10 may apply transmit diversity suitable for calling on channels with a PI function, such as L1 / L2 control channels or physical channels (PICH) dedicated to PI information, or call channels, or common data channels for transmission call information. The use of transmit diversity allows efficient transmission of call control information. In particular, transmission can be performed with less consumption of common radio resources of time, frequency and power.

In addition, the control unit 115 may control broadcast channels in order to use the same spreading codes and transmission times in them.

When a call is made between base stations and mobile stations, no control loop is created, although it is established during the transmission of conventional data channels. Thus, diversity in open loop transmission is appropriate. Examples of transmission diversity can be cited. STBC (Space Time Block Code, space-time block code) described in non-patent document 1, SFBC (Space Frequency Block Code, space-frequency block code) described in non-patent document 2, and TSTD (Time Switched Transmit Diversity, managed in Transmission Diversity) described in Non-Patent Document 3. When, according to TSTD, the transmit antenna changes with a constant cycle (time), either FSTD (Frequency Switched Transmit Diversity, or CDD (Cyclic Delay Diversity, cyclic delay diversity) in which The transmitting antenna changes for each frequency.

In addition, the transmitter 10 can apply time diversity for channels with a PI function, such as L1 / L2 control channels or physical channels (PICH) allocated for PI information, or call channels, or common data channels for transmitting call information.

The use of time diversity allows the transfer of call control information with high efficiency. In particular, less than the total number of radio resources of time, frequency and power may be spent for transmitting call control information. As a time diversity method, for example, iterative transmission can be applied. According to this embodiment, the transmitter side can be simplified, while on the reception side, better reception can be achieved by simply following the combination as described in Non-Patent Document 5. In addition, as an example of time diversity, for example, , incremental redundancy (IR) described in Non-Patent Document 6. According to this embodiment, although the transmission and reception operations may be more complex than iterative transmission, they can be achieved bend even better reception.

Further, when performing transmission several times for time diversity, frequency hopping within the frequency blocks pre-allocated for each of the transmission operations can be performed. According to this embodiment, in addition to the time diversity effect, a frequency diversity effect can be obtained, which allows for a better call quality.

Further, the blocks of radio resources allocated to the call channels can be changed with a certain cycle, as shown in Fig.7. According to this embodiment, the channel workload can be randomly distributed, which ensures efficient use of radio resources.

Further, as shown in FIG. 7B, a distributed transmission method or a localized transmission method is used to obtain the frequency diversity effect.

Finally, frequency diversity can be applied by repeating along the frequency axis or channel coding. According to this embodiment, a frequency diversity effect can be obtained, which allows for a higher call quality.

The following describes the receiver 20 according to one of the embodiments of the present invention with reference to figa.

According to this embodiment, the receiver 20 includes a broadcast channel receiving unit 202 into which received signals are received, a common data channel receiving unit 206 used as reception means, and a control unit 204 connected to the broadcast channel receiving unit 202 and the module 206 receiving common data channels and used as a means of extraction.

The broadcast channel receiving unit 202 receives the broadcast channels transmitted by the transmitter 20 and transmits them to the control unit 204. The control module 204 analyzes the necessary minimum system information contained in the broadcast channels, and controls the module 206 for receiving common data channels based on the system information. For example, control module 204 obtains information indicating a transmission frequency band of common data channels, based on information indicating common data channels by which system information elements other than the required minimum system information contained in the incoming broadcast channels are transmitted, and controls the reception module 206 common data channels based on the specified frequency band.

In the module 202 for receiving broadcast channels for different sectors of the same base station, different data is transmitted, however, if common data is partially used in the sectors, soft combining can be performed similarly to the case of call channels.

For example, the control module 104 transmits to the general data channel receiving module 206 information indicating frequency blocks of the common data channels serving to transmit system information elements other than the required minimum system information and information indicating reception times. A common data channel receiving unit 206 receives common data channels based on incoming information indicating frequency frequency blocks and reception times.

In module 206 for receiving common data channels for different sectors of one base station, different data is transmitted, however, if common data is partially used in sectors, soft combining can be performed. For example, the common data channel receiving unit 206 applies soft combining for common data channels to transmit call information.

The following describes a receiver 20 receiving call indicator information and call information, with reference to FIG.

The receiver 20 includes a call indicator information reception module 208 and a call information reception module 212, both of which receive signals, and a control module 210 connected to the call indicator information reception module 208 and the call information reception module 212.

Call indicator information receiving unit 208 receives call indicator information transmitted on L1 / L2 control channels or broadcast channels. If the call indicator information is transmitted on broadcast channels, the call indicator information module 208 may apply soft combining.

The call information receiving unit 212 receives the call information transmitted in the call channels or common data channels. The call information receiving unit 212 may apply soft combining for call information transmitted on call channels or common data channels.

The control unit 210 determines the presence of incoming information based on the call information received by the call indicator information receiving unit 208; if there is incoming information, the control unit 210 controls the call information receiving module 212 to receive the call information.

To perform soft combining between sectors, channel estimation values are needed for signals coming from individual sectors.

At receiver 20, broadcast channel reception unit 202 and call information reception unit 212 to obtain channel estimate values for individual sectors, and then soft combine channel estimate values based on all channel estimate values for individual sectors, pilot channels are used that are individual for the sectors. According to this embodiment, independent pilot channels are needed for sectors to receive common data channels, and thus this embodiment can be implemented without adding any other pilot channels.

In addition, if the common sector pilot channels are transmitted by the transmitter 10 separately, the receiver 20 can set the soft combining channel estimate value directly in the broadcast channel receiving unit 202 and the call information receiving unit 212. According to this embodiment, with soft combining, a simple channel estimate can be provided.

Next, with reference to Fig.9 describes a series of operations of the receiver 20 according to one of the embodiments of the present invention.

In step S502, the broadcast channel receiving module receives a broadcast channel (BCH).

In step S504, the control unit 204 extracts information indicating frequency blocks and the time distribution of the common data channels serving to transmit system information elements other than the required minimum system information from the control information contained in the broadcast channel.

In step S506, the control unit 204 transmits information indicating the frequency blocks and the time distribution extracted in step S504 to the common data channel receiving unit 206.

In step S508, the common data channel receiving unit 206 receives the common data channels based on information indicating frequency blocks and time distribution.

The following describes the timing over the allocation of user identifiers used for packet access. User identifiers are assigned to individual cells.

An example case of a request (call) from a mobile station is described with reference to FIG. 10.

In this case, in step S602, the mobile station requests a user ID from the base station. The identifier used in the request is transmitted as system information. Alternatively, a common system-predefined identifier may be used.

In step S604, the base station assigns a user ID and transmits the user ID to the mobile station.

In step S606, the mobile station transmits data using the user ID transmitted to it.

The following describes an exemplary case of a request for a mobile station (call to a mobile station) with reference to FIGS. 11 and 12.

When called from the network side, no user identifier for packet access is transmitted. After the call is answered from the mobile station, the base station transmits a packet access user ID from the cell receiving the response.

The following is a detailed description of the operation with reference to Fig.11.

In step S702, the base station transmits the call information to the mobile station.

In step S704, the mobile station transmits a user identifier request to the base station.

In step S706, the base station assigns a user ID for the mobile station and transmits the user ID to the mobile station.

In step S708, the mobile station transmits data using the transmitted user identifier.

According to this embodiment, since the mobile station transmits an identifier for packet access after the call to the network side, the delay time before the packet access starts may be slightly longer. On the other hand, it is possible to prevent the assignment of redundant user identifiers in those cells where the mobile station is not located, and the transmission of redundant control information. This fact may be advantageous in that the prevention of the assignment of redundant user IDs has a noticeable effect in large call areas, as in the case of location registration areas.

According to another embodiment, the packet identifier of the user may also be transmitted upon a call from the network.

The following is a detailed description of this embodiment with reference to FIG.

In step S802, the base station transmits the call information and the user ID to the mobile station.

In step S804, the mobile station transmits data using the transmitted user identifier.

According to this embodiment, if the call area of the identifier for packet access after calling the mobile station is large, as in the areas of location registration, i.e. if the request is simultaneously executed for a large number of cells, then a user identifier is assigned and transmitted for those cells in which the mobile station is not located, which leads to an increase in the processing volume and control signals in the base station. On the other hand, the mobile station can find out the user ID immediately after the call and begin packet access.

On the contrary, if the call area is small, as in separate cells, for example, if the network side, when identifying the cell in which the mobile station is located, can be limited to a small number of cells, then this embodiment may be advantageous because fewer redundant identifiers can be assigned user.

Next, a transmitter according to another embodiment of the present invention is described with reference to FIG.

In the foregoing embodiments, a case of transmitting broadcast channels in frequency domains has been described. In this embodiment, the transmitter 10 transmits broadcast channels in time domains.

The transmitter 10 according to the present embodiment, in addition to the components of the transmitter described with reference to FIG. 1, also includes an iterative transmission control module 106 connected to the system information generating module 101 ₁ .

The iterative transmission control module 106 determines the number of broadcast channels allocated within one radio frame, and controls the system information generating module 101 ₁ . In other words, the iterative transmission control module 106 determines how many times a broadcast channel needs to be transmitted within one radio frame. In this case, the multiplexing unit 104 multiplexes the broadcast channel in one radio frame, depending on the number of broadcast channels thus determined. As a result, the broadcast channel is transmitted within one radio frame one or more times.

In this case, the iteratively transmitted broadcast channel is transmitted in the same transmission format.

For example, if it is determined that the broadcast channel is allocated in the same radio frame twice, then the iterative transmission control module 106 allocates the broadcast channel in the same radio frame twice, as shown in FIG.

In addition, the iterative transmission control module 106 may map a broadcast channel to a subframe for transmitting a unicast channel. Then the broadcast channel is multiplexed in a unicast subframe.

Since multicast (MBMS, Multimedia Broadcast Multicast Service, multicast multicast service) subframes are processed as common spreading codes in cells, common pilot channels for multicast subframes are not available when determining the spreading code when searching for a cell. For this reason, the upper subframe is always made unicast (a cell-specific spreading code is applied) in order to eliminate the problem noted above, so a common pilot channel can be used to determine the spreading code when searching for a cell.

In addition, since cell-specific system information is broadcast on broadcast channels, broadcast channels are mapped to subframes for unicast transmission.

System information generation module 101 ₁ generates the necessary minimum system information based on the number of broadcast channels allocated in one radio frame, according to how it is determined by iterative transmission control module 106.

The transmission path encoder 102 ₁ always encodes the necessary minimum system information coming from the system information generation module 101 ₁ using the same method in the multiplexed subframes, and then transmits the encoded system information to the modulation module 103 ₁ . As a result, the transmitter 10 can always transmit the same signals. Thus, the receiver 20 can increase the SINR (signal to interference plus noise ratio, signal reception to total noise and interference) at the reception to improve the quality by combining the signals in the receiving module.

In addition, the receiver 20 can demodulate system information when receiving broadcast channels. In other words, system information can be demodulated at any time.

Next, a transmitter according to another embodiment of the present invention is described with reference to FIG.

If the broadcast channel is transmitted within one radio frame one or more times, then the transmitter 10 according to this embodiment, transmits various puncture patterns in multiplexed frames.

The transmitter 10 according to this embodiment, in addition to the components of the transmitter described with reference to FIG. 1, further includes a puncturing module 107 connected to the transmission path encoder 102 ₁ and an iterative transmission control module 106 connected to the puncturing module 107. A puncturing module 107 is connected to a modulation module 103 ₁ .

The iterative transmission control module 106 determines the number of broadcast channels allocated in one radio frame and controls the puncturing module 107. In other words, the iterative transmission control module 106 determines how many times a broadcast channel should be transmitted within one radio frame. In this case, the multiplexing module 104 multiplexes the broadcast channel within one radio frame, depending on the number of broadcast channels thus determined. As a result, a broadcast channel is transmitted within one radio frame one or more times.

In this case, the iteratively transmitted broadcast channel is transmitted in the same transmission format.

The necessary minimum system information coming from the system information generation module 101 ₁ is encoded in the transmission path encoder 102 ₁ and transmitted to the puncturing module 107. The puncturing unit 107 punctures (perforates) according to various puncturing patterns in the multiplexed subframes based on the number of broadcast channels allocated in one radio frame, as defined by the iterative transmission control unit 106. As a result, the iteratively transmitted broadcast channel is transmitted using various puncturing patterns.

According to this embodiment, a portion of the codewords may be transmitted at a low code rate. Receiver 20 can improve performance to increase encoding gain by combining in the receiving unit. As a result, errors can be reduced compared to non-puncturing options.

The following describes a receiver according to another embodiment of the present invention with reference to FIG.

The receiver 20, in addition to the components of the receiver described with reference to FIG. 8A, further includes an iterative reception control module 208 connected to the broadcast channel reception module 202.

The iterative reception control module 208 controls the broadcast channel reception module 202 to receive subframe signals in which the broadcast channels are multiplexed. For example, iterative reception control module 208 controls the reception of broadcast channels depending on the number of broadcasts of broadcast channels within a single radio frame.

The broadcast channel receiving unit 202 performs in-phase combining and demodulation of the subframe signals with multiplexed broadcast channels under the control of the iterative reception control unit 208.

In addition, the iterative reception control module 208 can code-mix and demodulate the signals of the subframes in which puncturing broadcast channels are multiplexed.

This application is based on applications: on priority applications of Japan No. 2006-010499 (filed January 18, 2006), No. 2006-031743 (filed February 8, 2006) and No. 2006-127991 (filed May 1, 2006), all the contents of which are incorporated herein by reference.

The transmitter, receiver, and communication method according to the present invention can be used in radio communication systems.

Claims (51)

1. The transmitter, which includes a module for generating system information, configured to generate system information; a multiplexing module configured to multiplex, in a broadcast channel, an element of information about a system frequency band from system information needed to search for a cell, and multiplex in a channel other than a broadcast channel another element of system information from system information other than a band information element a system multiplexed in a broadcast channel; and a transmission module, configured to transmit the broadcast channel and a channel other than the broadcast channel, wherein the system bandwidth information element indicates the system bandwidth of the base station containing the transmitter. 2. The transmitter according to claim 1, characterized in that the broadcast channel is defined as a physical channel, separated from the common data channel, and predefined in the system. 3. The transmitter according to claim 2, characterized in that the transmission of the broadcast channel occurs at the same center frequency as the transmission of the synchronization channel. 4. The transmitter according to claim 2, characterized in that the transmission of the broadcast channel occurs at the center frequency of the system bandwidth. 5. The transmitter according to claim 2, characterized in that the transmission of the broadcast channel occurs in a frequency band whose width is less than or equal to the width of the reception frequency band that all receivers should receive. 6. The transmitter according to claim 1, characterized in that the module for generating system information as system information necessary for cell search generates at least one information from the following list: information indicating a common data channel for transmitting a system element information other than a system information element necessary for cell search, and information indicating a cell identifier and the number of transmitting antennas. 7. The transmitter according to claim 1, characterized in that the system information generation module generates at least one information from the following list: tuning information, information about the interference level in the uplink, information indicating the configuration of the control channel of this cell, information about adjacent cells and intermittent reception cycle. 8. The transmitter according to claim 1, characterized in that the multiplexing module multiplexes information indicating a common data channel for transmitting a system information element other than a system band information element in a level 1 / level 2 control channel. 9. The transmitter according to claim 1, characterized in that it includes a call information generation module configured to generate call indicator information and call information based on a request signal from the network; the multiplexing module multiplexes the information of the call indicators either in the control channel level 1 / level 2, or in the channel of the call indicators, and multiplexes the information of the call either in the common data channel or in the call channel. 10. The transmitter according to claim 9, characterized in that the multiplexing module multiplexes information indicating the radio resources of the common data channel and the call channel, used to transmit call information, in the control channel level 1 / level 2. 11. The transmitter according to claim 9, characterized in that the multiplexing module multiplexes information indicating a common data channel and a call channel for transmitting call information in a broadcast channel. 12. The transmitter according to claim 9, characterized in that the transmission of the signal of the multiplexing module occurs at the same center frequency as the transmission of the synchronization channel. 13. The transmitter according to item 12, wherein the center frequency is equal to the center frequency of the system frequency band. 14. The transmitter according to claim 9, characterized in that the multiplexing module multiplexes a common data channel or call channel, used to transmit call information, in one block of radio resources or part thereof. 15. The transmitter according to claim 9, characterized in that the multiplexing module multiplexes the channel of the call pointers and the control channel level 1 / level 2 in blocks of radio resources that are different from each other. 16. The transmitter according to claim 1, characterized in that the data transmission module applies transmit diversity for a common data channel, a channel of call indicators and a channel of calls. 17. The transmitter according to claim 1, characterized in that the data transmission module applies for the common data channel at least time diversity or frequency diversity, or both. 18. The transmitter according to claim 1, characterized in that it includes a control module configured to control the broadcast channel in order to use common spreading code and timing distribution in sectors. 19. The transmitter according to claim 9, characterized in that it includes a control module configured to control a common data channel for multiplexing call information, in order to use common spreading code and timing in the sectors. 20. The transmitter according to claim 9, characterized in that it includes a control module configured to control the channel of the call pointers, which serves to multiplex the information of the call pointers, in order to use the common spreading code and the distribution of transmission over time in sectors. 21. The transmitter according to claim 1, characterized in that it includes an iterative transmission control module, configured to determine the number of broadcast channels allocated within one radio frame; the multiplexing module multiplexes the broadcast channel in one radio frame, depending on the number of broadcast channels determined in this way. 22. The transmitter according to item 21, wherein the multiplexing module displays the broadcast channel in a subframe for transmitting a unicast channel. 23. The transmitter according to item 21, wherein the iteratively transmitted broadcast channel is transmitted with a constant transmission format. 24. The transmitter according to item 21, characterized in that it includes a puncturing module, configured to puncture according to various puncturing patterns for multiplexed subframes; while the transmission of the iteratively transmitted broadcast channel occurs with various puncturing patterns. 25. A receiver including a broadcast channel receiving module, configured to receive a broadcast channel transmitted by a base station; an extraction module configured to perform a cell search based on the broadcast channel and retrieve information indicating a channel other than the broadcast channel and used to transmit a system information element other than the system bandwidth information element necessary for cell search; and a receiving module configured to receive a channel other than a broadcast channel based on information indicating a channel different from a broadcast channel and used to transmit a system information element other than a system bandwidth information element multiplexed in a broadcast channel, wherein the system bandwidth information element indicates the system bandwidth of the base station. 26. The receiver of claim 25, wherein the broadcast channel reception module applies soft combining if at least a portion of the received information is common to sectors. 27. The receiver of claim 25, wherein the receiving module applies soft combining if at least a portion of the received information is common to sectors. 28. The receiver according to claim 27, wherein the receiving module applies soft combining for a call channel or a common data channel for transmitting call information and / or for a call indicator channel for transmitting call indicator information. 29. The receiver according to claim 26, wherein the broadcast channel receiving module uses pilot channels individual for individual sectors in order to determine channel estimate values for individual sectors and determines channel estimate values with soft combining based on all channel estimate values for individual sectors. 30. The receiver according to p, characterized in that the broadcast channel reception module determines the channel estimation value with soft combining based on the pilot channel common to sectors. 31. The receiver according to item 27, wherein the receiving module uses pilot channels that are individual for individual sectors, in order to determine the channel estimate values for individual sectors, and determines the channel estimate values with soft combination based on all channel estimate values for individual sectors . 32. The receiver according to claim 27, wherein the broadcast channel reception module determines a soft combining channel estimation value based on a pilot channel common to sectors. 33. The receiver according A.25, characterized in that it includes an iterative reception control module, configured to control in-phase combination of subframe signals; this causes multiplexing of the broadcast channel in the subframe signals. 34. The receiver according A.25, characterized in that it further includes an iterative reception control module, configured to control code combination of subframe signals; this causes multiplexing of the broadcast channel in the subframe signals. 35. A communication method, comprising the following steps: generating system information;
multiplexing in a broadcast channel an element of information about a system frequency band from system information necessary for cell search; and transmitting a broadcast channel from a base station;
wherein the system bandwidth information element indicates the system bandwidth of the base station. 36. The method according to p. 35, characterized in that at the step of multiplexing in a channel other than the broadcast channel, multiplexing the system information element from the system information other than the system bandwidth information element multiplexed in the broadcast channel, and at the transmission step transmitting a channel other than a broadcast channel. 37. The method according to p. 35, characterized in that it contains the step of multiplexing in the control channel level 1 / level 2 information indicating a common data channel that serves to transmit another element of system information other than the information element of the system bandwidth. 38. The method according to clause 35, wherein the step comprises determining the number of broadcast channels allocated in a single radio frame; at the same time, at the multiplexing step, the broadcast channel is multiplexed in one radio frame depending on the number of broadcast channels determined in this way. 39. The method according to § 38, characterized in that in the step of multiplexing, a broadcast channel is mapped to a subframe for transmitting a unicast channel. 40. The method according to § 38, characterized in that it contains the step of transmitting an iteratively transmitted broadcast channel in the same format. 41. The method according to § 38, characterized in that it further comprises the following steps:
gouging according to various gouging patterns in multiplexed subframes,
transmitting an iteratively transmitted broadcast channel with various puncturing patterns. 42. The method according to p, characterized in that it further comprises the following steps:
generating call indicator information and call information based on a request signal from a network;
multiplexing call indicator information either in a level 1 / level 2 control channel or in a call indicator channel; and multiplexing the call information, either in a common data channel or in a call channel. 43. The method according to § 42, characterized in that it comprises the step of multiplexing information indicating radio resources either for a common data channel or for a call channel serving to transmit call information in a level 1 / level 2 control channel. 44. The method according to § 42, characterized in that it comprises the step of multiplexing information indicating radio resources either for a common data channel or for a call channel serving to transmit call information in a broadcast channel. 45. The method according to item 42, wherein the step of multiplexing transmit at the same center frequency as the transmission of the synchronization channel. 46. The method according to item 45, wherein the center frequency is equal to the center frequency of the system frequency band. 47. The method according to § 42, wherein in the multiplexing step, either a common data channel or a call channel serving to transmit call information is multiplexed in one block of radio resources or a part thereof. 48. The method according to § 42, characterized in that at the multiplexing step, either the channel of the call pointers or the control channel of level 1 / level 2 is multiplexed in radio resource blocks different from each other. 49. The method according to clause 36, characterized in that it further comprises the step of applying diversity when transmitting for a common data channel, a channel of call indicators and a channel of calls. 50. The method according to p. 35, characterized in that it further comprises the step of applying at least time diversity, or frequency diversity, or both for a common data channel. 51. The method according to § 42, characterized in that it further comprises the step of using a common spreading and transmission time distribution code in sectors for either a common data channel or a call channel, wherein multiplexing of call information in a common data channel or call channel.

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