WO2008069093A1

WO2008069093A1 - Communication system, base station, terminal, and communication method

Info

Publication number: WO2008069093A1
Application number: PCT/JP2007/073062
Authority: WO
Inventors: Nobuaki Takamatsu; Hironobu Tanigawa; Yasuhiro Nakamura
Original assignee: Kyocera Corporation
Priority date: 2006-11-29
Filing date: 2007-11-29
Publication date: 2008-06-12

Abstract

In a multi-service in which one radio link is shared by a plurality of services, a transmission queue is allocated for each of the services so that a flow within one radio link has a plurality of service priorities. A communication system (1) which performs communication by connecting a base station (2) to a terminal (3) by a single radio link includes communication control means (2-1) which uses the single radio link to add a different type of communication to the type of communication performed firstly so as to perform a plurality of different types of communication by using the single radio link.

Description

Specification

Communication system, base station, terminal and communication method

Technical field

[0001] The present invention relates to a communication system and a base station, a terminal, and a communication method used in the communication system.

Background art

[0002] QoS control of radio sections in mobile communication systems such as digital cellular phone systems and PHS systems is realized in the data link layer (MAC layer) in the OSI reference model. QoS (Quality of Service) is a function that guarantees transmission quality by setting a priority (service priority) for each communication on the network.

[0003] When QoS control is to be implemented in the radio section of such a mobile communication system, the IP header is removed when downlink (downlink) data arrives at the MAC layer. Cannot be controlled using the TOS field.

[0004] For this reason, service priority negotiation is performed in the process of call connection from a terminal, and QoS control is performed for each communication path.

[0005] Also, in the next-generation mobile communication system, when multiple services (also called multi-call) are introduced for one user, services with different service priorities may be mixed. It is done. For example, VoIP (Voice Over IP) (for example, the service with the highest service priority) and e-mail (for example, the service with the lowest service priority) that transmits and receives voice data converted into IP packets ) May be mixed.

[0006] Patent Document 1 discloses a method for managing a large number of independent simultaneous calls between a mobile communication network and a subscriber terminal.

Patent Document 1: Japanese Translation of Special Publication 2005-525934

Disclosure of the invention

Problems to be solved by the invention

[0007] In the conventional technology such as Patent Document 1 described above, only one radio link is allowed per user. Therefore, different service priorities cannot be mixed, or even if they can be mixed, a single radio link cannot have multiple service priorities! /, And! / There was a problem.

[0008] The present invention has been made to solve the above problems, and in a multi-service in which one radio link is shared by a plurality of services, a transmission queue is assigned to each service, and one radio link is provided. The purpose is to obtain a communication system, a base station, a terminal, and a communication method thereof. Means for solving the problem

[0009] In order to solve the above problems, a communication system according to the present invention is a communication system in which a base station and a terminal are connected by a single radio link to perform communication, and the single radio link is used. In addition to the first type of communication, communication control means for adding a type of communication different from the communication is provided (claim 1).

[0010] Thus, a plurality of different types of communication can be added using a single wireless link.

[0011] In addition, according to the type, a transmission unit that transmits a service identifier that specifies the type, and a reception unit that receives the service identifier, the communication control unit includes the received service identifier A transmission queue for storing communication data is assigned to each type corresponding to the above (Claim 2).

[0012] Thereby, a transmission queue for storing communication data is assigned to each type of communication corresponding to the service identifier, and communication control corresponding to the type of communication can be performed.

[0013] Further, the communication control means performs control so that the frequency of data transmission differs for each transmission queue according to the service identifier (claim 3).

[0014] In this way, by performing communication control according to the type of communication so that the frequency of data transmission differs for each transmission queue, after the packet is queued in the queue according to the communication service, The time to output can be changed, and the communication data rate can be changed for each communication service.

[0015] Further, the type is a communication application (claim 4).

[0016] Thereby, the effects of claims 1 to 3 can be obtained for various communication applications. And force S.

[0017] Further, the communication is performed according to the OFDMA scheme, and the communication control unit assigns a subchannel which is a communication channel in the OFDMA scheme according to the type (claim 5).

[0018] Accordingly, a single radio link is used in the OFDMA communication system.

V, multiple different types of communication can be performed.

[0019] Further, the communication control means assigns the number of subchannels corresponding to the service identifier for each transmission queue (claim 6).

[0020] Thereby, it is possible to make a difference in the data rate for each transmission queue according to the communication service.

[0021] Further, the transmission means transmits the service identifier through the subchannel (claim 7).

[0022] Thereby, in the communication system using the OFDMA scheme, it is possible to perform transmission of a plurality of different types using a single radio link by transmitting the service identifier in the subchannel.

[0023] The base station according to the present invention is a base station that communicates by connecting to a terminal through a single radio link, in addition to the type of communication that is initially performed using the single radio link, Communication control means for adding a different type of communication from the communication, and reception means for receiving a service identifier for specifying the type. The communication control means is provided for each type according to the service identifier. A transmission queue for storing communication data is assigned to each of the transmission queues, and control is performed so that the frequency of data transmission differs for each transmission queue in accordance with the service identifier (claim 8).

[0024] Thereby, it is possible to add different types of communication in addition to the communication that was initially performed, and further by performing communication control according to the type so that the frequency of data transmission differs for each transmission queue. Depending on the communication service, a base station that can be controlled to change the time from when a packet is queued to when it is output can be obtained.

[0025] Further, the communication is performed by an OFDMA system, and the communication control unit assigns a communication subchannel in the OFDMA system according to the type (claim 9). Yes

[0026] Thereby, in the base station that performs OFDMA communication, it is possible to perform transmission of a plurality of different types of communication using a single radio link by transmitting the service identifier in the subchannel. .

[0027] A terminal according to the present invention is a terminal used in a communication system that adds a type of communication different from the communication performed in addition to the type of communication initially performed using a single radio link with the base station. And a transmission unit that transmits a service identifier that specifies the type of communication according to the type of communication, and the transmission unit performs transmission of the service identifier on a subchannel that is a communication channel in the OFDMA scheme. Characteristic (claim 10).

[0028] Thereby, in a terminal that performs OFDMA communication, a service identifier transmission is included in the subchannel and transmitted, so that it differs in addition to the communication that was initially performed using a single radio link. Types of communication can be added.

[0029] A communication method according to the present invention is a communication system in which a base station and a terminal are connected by a single radio link to perform communication, and is a type of communication that is initially performed using the single radio link. In addition, a communication method for adding a communication of a type different from the communication, the step of transmitting a service identifier specifying the type according to the type, the step of receiving the service identifier, and the received A step of allocating a transmission queue for storing communication data for each type according to a service identifier is included (claim 11).

[0030] In this manner, different types of communication can be added in addition to the communication that was initially performed, and communication control according to the type of communication is performed so that the frequency of data transmission differs for each transmission queue. By doing so, the time from when a packet is queued to when it is output can be changed according to the communication service.

The invention's effect

[0031] According to the present invention, in a multi-service in which one radio link is shared by a plurality of services, a transmission queue can be assigned for each service, and a plurality of service priorities can be assigned to flows in one unspring link. , A base station, a terminal, and a communication method thereof can be obtained. Brief Description of Drawings

FIG. 1 is an explanatory diagram showing an OFDMA frame configuration used in a communication method according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a communication system according to an embodiment of the present invention.

FIG. 3 is a sequence diagram in the communication system according to the embodiment of the present invention.

FIG. 4 is a diagram showing a structure of a MAC frame in the communication system according to the embodiment of the present invention.

FIG. 5 is a table showing an example of weights assigned to service priorities corresponding to different types of communication applications in the communication system according to the embodiment of the present invention.

Explanation of symbols

[0033] 1 Communication System

2 Base station

2-1 Communication control means

2-2 Transmission method

2-3 Receiving means

3 terminal

3- 1 Transmission method

3- 2 Reception means

4 network

BEST MODE FOR CARRYING OUT THE INVENTION

First, prior to the description of the communication system according to the present embodiment, the frame structure of OFDMA used in the communication system will be described with reference to the explanatory diagram of FIG.

[0035] FIG. 1 shows, for example, the frame structure of OFDMA when there are four time slots (S1 to S4) used in the PHS system, the vertical axis is the frequency axis, and the horizontal axis is the time axis. .

In FIG. 1, both the downlink period and the uplink period are 2 with respect to the frequency axis.

It is divided into 8 frequency bands. The subchannel of the first frequency band is called the control subchannel and is used in the control channel (CCH). Note that the first above The frequency band may be either the highest frequency band or the lowest frequency band. The control channel subchannel indicates which subchannel of each time slot is used in each frequency band.

[0037] The example of Fig. 1 is an example of a PHS system, and the base stations that can be specified by the control subchannels C1 to C4 are four base stations. In the PHS system, the control channel is transmitted intermittently every 100 ms.

[0038] The remaining 27 frequency bands include a traffic subchannel T1 for transmitting and receiving data.

~ T108, 27 in the frequency direction and 4 in the time axis direction, consisting of 108 subchannels in total.

[0039] This traffic subchannel includes an anchor subchannel and an extra subchannel.

[0040] An anchor subchannel is used to notify each terminal of which subchannel is used and which terminal is used, and the ability to correctly exchange data by retransmission control between the base station and the terminal. This is a subchannel for use in negotiation.

[0041] An extra subchannel is a subchannel that transmits data that is actually used. A plurality of extra subchannels can be assigned to one terminal. In this case, the greater the number of allocated sub-subchannels, the wider the band, so high-speed communication becomes possible.

Hereinafter, embodiments of a communication system according to the present invention will be described in detail with reference to the drawings. FIG. 2 is a configuration diagram of a communication system according to the embodiment of the present invention.

[0043] As shown in FIG. 2, the communication system according to the embodiment of the present invention is a communication system 1 in which a base station 2 and a terminal 3 are connected by a single radio link to perform communication. 2 is connected to network 4.

[0044] The base station 2 controls communication of the base station, communication control means 2-1 for performing a plurality of different types of communication using a single radio link, and transmits data and voice to the terminal connected to the antenna. Transmitting means 2-2 and receiving means 2-3 for receiving data and voice from the terminal.

[0045] The terminal 3 includes transmission means 2-2 connected to an antenna and transmitting data and voice to the base station, and reception means 2-3 receiving data and voice from the base station. The communication system according to this embodiment will be described in detail with reference to FIG. 3 which shows an example of a communication procedure sequence between the terminal 2 and the base station 3.

[0047] The sequence in Fig. 3 is an example of a case where the terminal 2 sends a voice call and receives an E-mail during voice communication (call).

[0048] (1) When the user performs a voice call transmission operation at the terminal 3, the transmission means 3-1 of the terminal 3 transmits a link channel (LCH) establishment request to the connected base station 2.

[0049] (2) The communication control means 2-1 of the base station 2 that has received the link channel (LCH) establishment request allocates an anchor subchannel (ASCH) based on the carrier sense, and the transmission means 2-2 The location of the anchor subchannel (ASCH) is notified to the terminal by link channel (LCH) allocation.

[0050] (3) The terminal 3 that has received the link channel (LCH) assignment by the receiving means 3-2 is the transmitting means 3

In step 1, a service flow addition request is transmitted to the base station 2. The service flow addition request includes a service identifier for identifying the service flow to be communicated by the terminal 3 and the service priority requested by the communication application.

[0051] Specifically, the requested service is transmitted to the base station as a message using the extra subchannel (ESCH). At this time, the value of the CD field as the service identifier is (0, 0, 0).

[0052] (4) Upon receiving the service flow addition request, the communication control means 2-1 of the base station 2 stores the communication data corresponding to the type of service for the service flow requested by the terminal 3. A queue (transmission queue 1) is assigned, and the data transmission frequency is controlled so as to satisfy the service priority required for voice communication that is the type of service concerned.

[0053] Next, the transmission means 2-2 of the base station 2 transmits a service flow addition confirmation to the terminal, notifying that preparation for exchanging data is completed on the base station side.

(5) The terminal 3 that has received the service flow addition confirmation by the receiving unit 3-2 transmits a radio bandwidth request to the base station side by the transmitting unit 3-1.

[0055] (6) The communication control means 2-1 of the base station 2 that has received the wireless bandwidth request secures a wireless bandwidth for the service. In order to notify this reserved radio band, transmission means 2-2 Notifies the terminal of the position of the subchannel used for communication by MAP and starts voice communication (communication).

At this time, the frequency of data transmission is controlled so that the transmission queues of both the base station 2 and the terminal 3 satisfy the service priority requested corresponding to the voice communication as the service type.

[0057] The data receiving side identifies a communication application in which the arrived data is to be received by the service identifier included in the received data.

[0058] (7) Ability to notify the packet reception by e-mail when e-mail arrives at base station 2 for the user in voice communication. It has recognized.

[0059] When the base station 2 determines that the terminal 3 that should receive the call is in communication, the paging is not transmitted and the same processing as in (4) is performed. In this case, the communication control means 2-1 assigns the service priority assigned to the e-mail service, which is the type of the service, as the service priority assigned to the transmission queue. In addition, a transmission queue (transmission queue 2) different from that notified in (4) is allocated, and the frequency of data transmission is controlled so that the service priority required for the e-mail service is satisfied. To do. At this time, the anchor subchannel changes the allocation of the V and extra subchannels for data transmission for each service according to the service priority.

[0060] In this way, the base station 2 and the terminal 3 are connected by a single radio link, and data assigned with different service identifiers are passed through the base station 2 and the terminal 3, and the single radio link is connected by a plurality of service flows. Multi-service is realized by sharing.

[0061] Next, a service identifier that identifies the type of communication according to the type of communication will be described. FIG. 4 is a diagram showing the structure of the MAC frame in the present embodiment.

[0062] In the communication system according to the present embodiment, the CD field for identifying control information and data in the MAC header part is extended to a 3-bit area (Bitl, Bit2, Bit3). Features.

[0063] The value of the CD field (Bitl, Bit2, Bit3) force θ, 0, 0) indicates that the content of the MAC payload is MAC control data. In other cases, that is, (0, 0) , 1) to (; 1, 1, 1 ), This value indicates the service identifier (SI to S7) used by the user.

[0064] Next, a method for transmitting and receiving service flows having different service identifiers over a single radio link will be described. FIG. 5 is a table showing an example of a correspondence relationship between communication identifiers different from service identifiers and weights assigned to service priorities.

As shown in FIG. 5, priorities are assigned to the service priorities Priority 1 to Priority 5 in advance. In other words, the service priority is determined according to the service identifier.

[0066] For example, consider a multi-service using the Priority 1 service (service identifier: S1) and the Priority 5 service (service identifier: S5) in a single wireless link in the table of FIG.

[0067] In this example, if the radio band reserved for data transmission is sufficient to satisfy the quality of both services, the band necessary for service S1 is reserved for data transmission of service S1. All that remains is allocated for data transmission of service S5.

[0068] Also, if the radio band reserved for data transmission is sufficient to satisfy both service qualities, the band reserved for service S1 and the band reserved for service S5 The ratio is the ratio of the weights assigned to each priority. In this example, the ratio of the weights of S1 and S5 is 10: 2, and the bandwidth allocation of S1 and S5 shares the reserved bandwidth at a ratio of 10: 2.

[0069] Thereby, it is possible to avoid continually allocating a radio band only to a service with a high service priority.

Claims

The scope of the claims

[1] In a communication system in which a base station and a terminal are connected by a single wireless link for communication, in addition to the type of communication initially performed using the single wireless link, the communication is different. A communication system comprising communication control means for adding a type of communication.

[2] A transmission unit that transmits a service identifier that specifies the type according to the type, and a reception unit that receives the service identifier,

The communication system according to claim 1, wherein the communication control unit allocates a transmission queue for storing communication data for each type according to the received service identifier.

[3] The communication control means includes:

3. The communication system according to claim 2, wherein control is performed so that the frequency of data transmission differs for each transmission queue according to the service identifier.

[4] The communication system according to any one of claims 1 to 3, wherein the type is a communication application.

[5] Communicate using the OFDMA method,

5. The communication system according to claim 1, wherein the communication control means assigns a subchannel that is a communication channel in the OFDMA scheme according to the type.

6. The communication system according to any one of claims 2 to 5, wherein the communication control unit allocates the number of subchannels corresponding to the service identifier for each transmission queue.

7. The communication system according to claim 5, wherein the transmission means transmits the service identifier through the subchannel.

[8] In a base station that communicates with a terminal via a single wireless link,

A communication control means for adding a different type of communication to the first type of communication using the single radio link,

Receiving means for receiving a service identifier for specifying the type, and the communication control means sends communication data for each type according to the service identifier. Assign each transmit queue to store,

A base station that controls the frequency of data transmission to be different for each transmission queue according to the service identifier.

[9] Communicate using the OFDMA method,

9. The base station according to claim 8, wherein the communication control unit assigns a communication subchannel in the OFDMA scheme according to the type.

[10] In a terminal used for a communication system that adds a type of communication different from the communication of the type first performed using a base station and a single radio link,

According to the type of communication, comprising a transmission means for transmitting a service identifier that identifies the type of communication,

The terminal characterized in that the transmission means transmits the service identifier through a subchannel which is a communication channel in the OFDMA scheme.

[11] In a communication system in which a base station and a terminal are connected by a single radio link for communication, in addition to the type of communication initially performed using the single radio link, the communication is different. A communication method for adding types of communication,

Depending on the type, transmitting a service identifier identifying the type; receiving the service identifier;

Allocating a transmission queue for storing communication data for each type according to the received service identifier;

A communication method comprising: