JP3208653B2 - Automatic retransmission control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station controller, a plurality of base stations, and a plurality of mobile stations, wherein a radio communication channel between the base station and the plurality of mobile stations is controlled by a control channel and an information channel. And a demand-assigned TDMA (Time Divis) for allocating as required as an access method for each wireless communication channel.
The present invention relates to an automatic retransmission control method used in a wireless communication system using an ion multiple access (ion Multiple Access) method.

[0002]

2. Description of the Related Art In a communication system for performing data transmission using a transmission line having a relatively high error occurrence rate such as a radio line,
Conventionally, an automatic retransmission request (ARQ: Automatic Retransmission) has been used to perform highly reliable data transmission with few errors.
(Peat reQuest) method is being studied. In this automatic retransmission request method, the data transmitted by the transmitting side is subjected to error detection encoding according to a predetermined procedure and transmitted, and the receiving side performs error detection according to the procedure corresponding to the above procedure, and when an error is detected, Is a transmission method for automatically sending a retransmission request to the transmission side.

[0003] As a basic automatic repeat request method, FIG.
0, Stop & Wait ARQ scheme, Go-Back-N ARQ scheme, Selecti
Three schemes of the ve-repeat ARQ scheme are being studied. The Stop & Wait ARQ scheme divides data transmitted by a transmission side into a plurality of blocks, transmits one block, and then receives a reception success signal (A
ck) or a reception failure retransmission request signal (Nack) is received without receiving the next block. This method simplifies both the procedure and the device. On the other hand, in the Go-Back-N ARQ scheme, the transmitting side continuously transmits a plurality of blocks without waiting for a response (Ack or Nack) from the receiving side, and receives a retransmission request signal from the receiving side. In this system, not only the block requested to be retransmitted, but also transmitted blocks subsequent to the block are continuously retransmitted.

[0004] Also, Selective-Repeat
In the ARQ scheme, similarly to the Go-Back-N ARQ scheme, the transmitting side sequentially transmits blocks without waiting for a response from the receiving side, and the receiving side performs error detection for each received block, and performs error detection for each block. A response is returned to the block, and the transmitting side retransmits only the block that is the reception failure retransmission request signal in the response from the receiving side, and if an error is detected in the received response, the response is successful / failed. This is a method for retransmitting a block for which a confirmation is to be made.

[0005] Of the above three methods, Selective
The e-Repeat ARQ scheme can obtain the highest transmission efficiency, but it has a problem that the apparatus becomes complicated and a buffer memory having a large capacity is required. There is a problem that use for body communication is difficult.

A method of performing an automatic retransmission request (ARQ) for mobile radio data transmission is disclosed, for example, in Japanese Patent Laid-Open No. 5-160.
No. 817. Hereinafter, a conventional automatic retransmission request in this mobile communication system will be described with reference to FIG.
This will be described with reference to FIG.

FIG. 11 is a system configuration diagram in a conventional example. In FIG. 11, reference numeral 10 denotes a transmitting-side wireless communication device;
Reference numeral 0 denotes a receiving-side wireless communication device. Next, the configuration of the transmitting-side wireless communication device will be described. 11 is a communication controller, 12
Is an encoding unit that encodes transmission data according to a predetermined encoding rule, 13 is a buffer memory that temporarily stores transmission data, 14 is a carrier that modulates a carrier of a predetermined frequency with the encoded transmission data, and a transmission / reception switch 16 is operated. A transmitter 15 transmits the signal from the antenna 17 via the antenna 17, and a receiver 15 receives and modulates the carrier received by the antenna 17. Next, the configuration of the receiving-side wireless communication device will be described. 21
Is a communication control unit, 22 is an encoding unit that decodes received data that has been encoded and received, 23 is a buffer memory that temporarily stores received data, and 24 is a carrier that modulates a carrier of a predetermined frequency with encoded transmission data. , Transmission / reception switch 26
Is a transmitting unit for transmitting the signal from the antenna 27 via the antenna 27, and a receiving unit 25 for receiving and modulating the carrier received by the antenna 27.

FIG. 12 is a sequence diagram showing a retransmission procedure of the automatic retransmission request method in the conventional example.
TXB is a transmission block number, RXB is a reception block number, TACK is the latest transmission success block number confirmed by the transmission side, and RACK is a reception block confirmed by the reception side. In addition, as the content of the determination of the receiving block on the receiving side,
s is a block that is valid without error, e is a block that is invalid because an error is detected, and d is a block that is received without error but is invalid because the block number is not next to RACK. A solid line or a dotted line with a cross in the figure indicates that an error has occurred during wireless transmission. Also,
The round trip time N (the time required for the transmitting side to transmit a block and receive a response, expressed in the number of blocks transmitted by the transmitting side) in the conventional example is 4
And

Next, the operation of the conventional automatic repeat request method will be described with reference to FIGS. The automatic retransmission request method described in this conventional example is based on Go-Back-N ARQ.
Based on the scheme, this is a scheme in which the retransmission procedure is switched between when the transmitting side detects an error in the response and when it does not detect an error. The transmission-side wireless communication device 10 divides the transmission data stored in the buffer memory 13 into a plurality of blocks, and assigns a continuous block number (TXB) to each block data. Next, the transmission success block number counter (TACK) in the communication control unit 11 is reset to 0. Next, a line connection request is made to the receiving side, and after the line is established,
The data blocks are read out from the buffer memory 13 in numerical order, the encoding unit 12 performs error detection encoding according to a predetermined encoding rule, and transmits the data blocks through the transmission unit 14.

On the other hand, when the line connection is first established, the reception-side radio communication device 20 resets a reception confirmation block number counter (RACK) in the communication control unit 21 in the same manner as the transmission side. Next, when the data is received through the receiving unit 25, error detection of the received data block is performed according to the procedure of the receiving side of the Go-Back-N ARQ scheme, it is determined whether or not to update the RACK, and a response is sent to the transmitting side. Returns a signal.

On the other hand, the transmitting side continues block transmission without waiting for a response from the receiving side, and detects an error of the response received after the round trip time by the same error detecting function as that of the receiving side. If the response is received without error and is a retransmission request, the process returns to the block of the next number of TACK and retransmits N blocks from there. On the other hand, if an error is detected in the received response signal, the signal block is discarded, and R
Processing such as comparison with ACK and updating of TACK is not performed.
Here, since there is a possibility that a retransmission request has been issued without updating the RACK, a retransmission request will be made by a reception success signal or a reception failure retransmission request signal in the response (RA
Selective-R that retransmits only one data block of the number that was to be returned as CK)
It switches to the repeat ARQ retransmission procedure and waits for the next response.

If the next response is correctly received and the RACK has been updated to plus one, the transmission is continued from the number following the block number transmitted before retransmission. If a retransmission request is issued without updating RACK, Go-Back-
Switching to the N ARQ scheme retransmission procedure is performed, but in this case, the Select
Only the remaining blocks excluding the one block retransmitted by the ve-repeat ARQ scheme are retransmitted to return to a normal communication state. Normal Go-Ba for the receiving side
In accordance with the procedure of the ck-N ARQ scheme, a method has been devised in which error detection of a received data block is performed by using error detection coding (actually decoding), RACK is updated by the RACK and the reception block, and returned as a response to the transmission side. Have been.

[0013]

In the conventional automatic retransmission request method, there is a problem that an error in a channel for transmitting a response causes a retransmission operation and lowers transmission efficiency.

In addition, since the conventional automatic retransmission request method targets only a bidirectional symmetric communication channel, a sequence number that can correspond to the maximum speed is required in order to make an automatic retransmission request even in variable speed communication, There is a problem that the overhead is increased due to the expression of the sequence number.

Further, in the conventional automatic retransmission request method, since a sequence number is used, if an error occurs in a feedback channel in consecutive TDMA frames, the same sequence number is generated and burst data cannot be distinguished. There was a point.

In the conventional automatic repeat request method, when an error occurs in a feedback channel,
The receiving device must retransmit the burst data reception success signal or the burst data reception failure signal again, and there is a problem that the delay increases accordingly.

Further, in the conventional automatic retransmission request method, there is a problem in that, when burst data to be retransmitted increases, transmission delay increases and throughput decreases.

The present invention has been made to solve such a problem, and uses a control channel for an automatic retransmission request, and when an error is detected, the amount of burst data to be retransmitted. It is an object of the present invention to obtain an automatic retransmission control method that suppresses as much as possible.

[0019]

An automatic retransmission control method according to the first invention (which is the same as the conventional automatic retransmission request method) comprises at least one base station for managing a radio zone, and the base station. A request between the base station and the base station via a radio communication channel including a base station control device that integrally manages the information channel, an information channel that transmits information for a user, and a control channel that allocates a TDMA slot of the information channel. And at least one mobile station accessed using a demand-assigned TDMA scheme that performs assignment according to the base station or a transmission-side apparatus that is used in a wireless communication system configured to transmit burst data. The mobile station or the base station, which is a receiving device that receives the burst data from the mobile station, transmits a burst data reception success signal. Ack) and a means for using the control channel as a feedback channel for transmitting a burst data reception failure signal (Nack). The transmission of the burst data reception success signal and the burst data reception failure signal on the control channel includes an information channel. Than the error correction code applied to the transmitted burst data,
It is provided with means for adding an error correction code for increasing the codeword length to the information length.

In the automatic retransmission control method according to a second aspect of the present invention, the receiving apparatus includes error detecting means for performing error detection on each burst data received from the transmitting apparatus in units of TDMA frames, and the error occurs. Slot position detecting means for detecting a TDMA slot position corresponding to the burst data; and a reception failure signal for each TDMA frame unit, the information being capable of expressing the slot position for each of the transmitting side apparatuses transmitting the erroneous burst data. And transmission means for transmitting the frame on a control channel which is a feedback channel of the frame after a predetermined time.

According to a third aspect of the present invention, in the automatic retransmission control method, the transmitting apparatus transmits burst data after the burst data corresponding to the slot position added to the reception failure signal received on the control channel which is a feedback channel. Burst data reading means for reading from the storage unit in the storage unit, and the burst data read from the storage unit by the burst data reading means are allocated to the transmitting apparatus in a TDMA frame after a predetermined time. And retransmission means for retransmitting TDMA frames in order from the temporally first slot in one or more slots.

According to a fourth aspect of the present invention, in the automatic retransmission control method, the transmitting apparatus detects an error in reception information of a control channel which is a feedback channel transmitted from the receiving apparatus; Transmitting means for transmitting information indicating success or failure of reception of the control channel together with burst data on an information channel in a TDMA frame after a predetermined time in accordance with the presence or absence of an error in the transmission side device. Detects an error in the control channel, the burst data reception success signal (Ack) and the burst data reception failure signal (Nac)
All the burst data transmitted in the frame for which the delivery confirmation was scheduled to be obtained in k) is transmitted again.

In the automatic retransmission control method according to a fifth aspect of the present invention, the receiving apparatus performs error detection on each burst data received from the transmitting apparatus in units of TDMA frames, and the error has occurred. Slot position detecting means for detecting the slot position of the TDMA slot corresponding to the burst data; and a frame number for identifying the frame and the slot position for each transmitting apparatus which has transmitted the erroneous burst data. To the reception failure signal, and after a predetermined time T
Response means for transmitting on a control channel which is a feedback channel in a DMA frame, wherein the transmitting apparatus reads out the burst data specified by the information representing the frame number and the slot position from a storage unit. It comprises a reading means and a retransmitting means for retransmitting designated burst data in order from the front of one or more TDMA slots capable of transmission.

In the automatic retransmission control method according to a sixth aspect of the present invention, when one or more of the received burst data is incorrect, the receiving side device is required to retransmit the burst data and transmit the untransmitted burst data. A slot number calculating means for calculating the number of slots, and a slot number requesting means for requesting the calculated number of slots together with a reception failure signal on a control channel when the receiving apparatus is a mobile station; Is a base station, a TDMA slot allocating means for allocating a new TDMA slot in accordance with the calculated number of slots, and a control of notifying a change of the allocated slot to the mobile station as the transmitting apparatus together with a reception failure signal. And means for notifying an assigned slot change performed in the channel.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a system configuration diagram showing one embodiment of a communication system including an automatic retransmission control method according to the present invention. In FIG. 1, reference numeral 1 denotes a base station controller that integrally manages base stations, reference numerals 2a to 2d denote wireless zones, reference numerals 3a to 3e denote mobile stations moving between the wireless zones 2a to 2d, and reference numerals 4a to 4d denote wireless zones 2a to 2d. The base station to manage. This system configuration diagram is used in the following embodiments.

FIG. 2 is a frame configuration diagram showing an embodiment of a configuration of a TDMA frame (hereinafter referred to as a TDMA frame) used in the automatic retransmission control method according to the present invention. In this example, the same TDMA frame is used. This figure shows a configuration in which a frame is divided into a control channel and an information channel. FIG. 3 is a sequence diagram showing an operation sequence when communication is performed between the base station 4 and the mobile station 3 using the frame configuration shown in FIG. 2. In this example, the mobile station 3 transmits the base station to the base station. 4 shows an operation sequence when transmitting burst data to the C.4. This TDMA frame configuration diagram is also used in the following embodiments.

Next, the operation of this embodiment will be described with reference to FIG. 1, FIG. 2 and FIG. As shown in FIG. 1, a plurality of mobile devices 3 existing in the same wireless zone 2 and
Can be communicated with one base station 4 that manages the communication via a wireless communication channel. Here, a demand assignment type TDMA is used as a wireless communication access method between the mobile station 3 and the base station 4. In the present embodiment, as shown in FIG. 2, a slot group for a control channel exists in the first half of the same TDMA frame, and the slot group is time-division multiplexed (TDD) into an uplink slot and a downlink slot.
The uplink slot group can be acquired by each mobile station 3 as an uplink control channel by a random access scheme, and the uplink control channel once acquired is used by the mobile station 3 until a release message from the mobile station 3 is transmitted. it can. Note that “up” indicates a direction from the mobile station 3 to the base station 4, and “down” indicates a direction from the base station 4 to the mobile station 3.

When the mobile station 3 has acquired the upstream slot, the base station 4 automatically secures a downstream slot having a slot number corresponding to the slot number of the acquired slot. Also, it is assumed that all the mobile devices 3 existing in the wireless zone 2 always secure the control channel. Note that the mobile device 3 that cannot secure the control channel cannot perform communication in the wireless zone 2.

The mobile station 3 in which the transmission burst data exists makes an information channel allocation request to the base station 4 by using the uplink control channel among the control channels configured as described above. However, the mobile device 3 transmits the allocation request by explicitly indicating the number of uplink slots and the number of downlink slots of the required information channel, respectively, according to the conditions such as up / down speed communication, one-way communication, and variable speed communication. The base station 4 that has received the above allocation request from the mobile station 3 uses the downlink control channel and, if there is a slot that can be allocated, according to the number of slots requested for the mobile station 3 using the downlink control channel. The information channel slot is allocated.

Thus, the base station 4 can cope with a case where the mobile station 3 requests vertical and lower speed communication, a case where one-way communication is requested, and a case where variable speed communication is performed. When there is no slot that can be assigned, the base station 4 transmits a signal to reject the assignment request using the downlink control channel. Furthermore, by assigning a codeword length to the error correction redundant bits of the control channel longer than that of the information channel, the error correction capability of the control channel is made higher than that of the information channel.

Next, when the mobile station 3 to which the information channel slot is allocated as described above transmits burst data, an automatic retransmission request for the burst data and a retransmission operation based on the request will be described with reference to FIG. Will be explained. When the mobile station 3 issues a request for uplink one-way communication to the base station 4 using the slot # 1 of the uplink control channel, the base station 4
Allocates # 1 to # 3 slots of the information channel for the mobile station 3 concerned. The mobile station 3 that has received the slot assignment transmits the transmission burst data in units of TDMA frames, three burst data at a time. In contrast, base station 4 has 3
Using the downlink slot # 1 of the control channel for each frame (that is, for a total of nine received burst data units of 3 frames × 3 slots), a burst data reception success signal (Ac
k) or a burst data reception failure signal (Nack) is transmitted.

That is, if all of the nine received burst data are normally received, a reception success signal is output. If at least one of the nine burst data contains an error, the reception success signal is output. A burst data reception failure signal with the number of the first burst data is transmitted using downlink slot # 1 of the control channel.

For example, the TDMA frame of FIG.
In step 6, when the base station 4 detects an error in the burst data 14 and 16 from the mobile station 3, a burst data reception failure signal to which the number 14 of the first burst data among the burst data in which the error has occurred is added. It transmits to mobile station 3 using downlink slot # 1 of the control channel. When the mobile station 3 receives the burst data reception failure signal, nine burst data (14,
15, 16) (17, 18, 19) (20, 21, 22)
2) is transmitted to the base station 4 using the uplink slots # 1 to # 3 of the information channel.

In this embodiment, the burst data reception success signal or the burst data reception failure signal is transmitted on the downlink control channel every three frames, but the burst data reception signal is transmitted for each frame or for a plurality of frames. A success signal or a burst data reception failure signal may be transmitted. Further, the burst data reception failure signal transmits all the wrong burst data numbers (burst data 14 and burst data 16 in FIG. 3) among the nine received burst data, and the mobile station 3 transmits the burst designated by the base station 4. The data may be retransmitted.

According to this embodiment, there is an effect that the automatic retransmission request and the automatic retransmission can be performed without setting the information channel required for the automatic retransmission request even in the vertical different speed communication and the one-way communication. .

Embodiment 2 FIG. 4 is a frame configuration diagram showing another embodiment of the automatic retransmission control method according to the present invention, and also shows a slot position corresponding to error burst data transmitted from the receiving device to the transmitting device. I have. FIG. 5 is a sequence diagram showing an operation sequence when transmission is performed using the frame shown in FIG. 4, and shows a sequence for transmitting burst data from the mobile station 3 to the base station 4.

Next, the operation of this embodiment will be described with reference to FIGS. Note that the assignment of slots to the mobile device 3 is the same as that in the first embodiment, and a description thereof will not be repeated. Here, the mobile station 3 makes a request for uplink one-way communication to the base station 4 in slot # 1 of the uplink control channel, and the base station 4 transmits the information channels # 1 to # 3 to the mobile station 3. The operation after the state of the assignment is described.

As shown in FIG. 4, the base station 4 performs error detection on all the burst data received in each slot in frame units, and when an error is detected, the base station 4 uses this burst data as error detection information. 1 is set, and if no error is detected and no burst data is detected, "0" is set as error detection information, and one frame composed of slots # 1 to #n of the information channel is set. For example, as shown in FIG. 4, if an error occurs in slot # 3 and slot #n as shown in FIG.
(0010 ... 1).

Next, based on the error detection information E and the position information of the slot allocated to each mobile station 3, the base station 4 transmits a burst data reception success signal and a burst data reception failure signal to be transmitted to each mobile station 3. Create information to be added to. That is, in the case of the mobile station 3a, since slots # 1, # 2, and # 3 of the information channel are allocated,
Information represented by the first, second, and third bits from the top of the error detection information E, that is, (001) in the above-described example is added to the burst data reception failure signal and transmitted in the downlink slot of the control channel.

The burst data reception success signal and the burst data reception failure signal may be replaced with the error detection information E.

FIG. 5 shows the operation of transmitting the burst data from the mobile station 3 to the base station 4 and the automatic retransmission control of the burst data reception success signal and the burst data reception failure signal using the control channel in the present embodiment. ing. In FIG. 5, mobile station 3 transmits three burst data for each frame using uplink slots # 1 to # 3 of the assigned information channel. The base station 4 that has received the burst data detects an error in each burst data, and transmits a burst data reception failure signal to which the slot position of the burst data in which the error is detected is added using the downlink slot # 1 of the control channel. The mobile device 3 that has received the burst data reception failure signal retransmits the burst data at the slot position indicated by the information of the previously transmitted frame.

For example, as shown in FIG. 5, when an error of burst data 4 is detected in burst data (4, 5, 6) received by base station 4 in TDMA frame # 2, downlink slot # 1 of the control channel Using,
The burst data reception failure signal is transmitted to the mobile station 3 with (100) added. Upon receiving the burst data reception failure signal, the mobile station 3 again transmits three burst data (4, 7, 8) composed of the burst data 4 and the next burst data to uplink slots # 1 to ## of the information channel.
3 to the base station 4 (TDMA frame
3).

Further, in the TDMA frame # 4, when an error in the burst data 10, 11 is detected in the burst data (9, 10, 11) received by the base station 4,
Using the downlink slot # 1 of the control channel, (011) is added to the burst data reception failure signal and transmitted to the mobile station 3. Upon receiving the burst data reception failure signal, the mobile station 3 again transmits three burst data (1) composed of the burst data 10 and 11 and the next burst data.
0, 11, 12) are assigned to uplink slots # 1 to # 1 of the information channel.
Transmit to base station 4 using # 3 (TDMA frame
5).

In this embodiment, information indicating the result of error detection is also included in the burst data reception success signal (FIG. 5).
(000)), the transmission of the burst data reception success signal may be omitted. Also, in the present embodiment, only the burst data specified by the burst data reception failure signal is retransmitted, but all burst data after the specified first burst data may be retransmitted. In this case, the error detection information up to the slot where the first error occurred in the frame, that is, for example, when E = (010), may be expressed as (01). Further, it may be represented by the slot number where an error first occurred.

According to this embodiment, the information added to the burst data reception failure signal transmitted on the control channel, which is a feedback channel, is the number of bits corresponding to the number of slots allocated to the mobile station 3, and at most one frame When only the burst data in which an error is detected is retransmitted as shown in the present embodiment, the number of information channels is smaller than the information used for the sequence number, and the amount of information transmitted on the control channel can be reduced. It has the effect of being able to do it. Furthermore, since a retransmission request can be made only in the form depending on the configuration of the TDMA frame, that is, only with the number of slots allocated to the mobile station 3, when the number of allocated slots is variable, compared with the case of using a fixed sequence number, This has the effect of reducing processing.

Embodiment 3 FIG. 6 is a transmission burst data configuration diagram showing a transmission burst data configuration showing another embodiment of the burst data transmitted on the information channel in the present invention, and FIG. FIG. 9 is a sequence diagram showing a sequence in a case where communication is performed between the mobile station 3 and the base station 4 using the indicated transmission burst data, and shows a flow of processing of automatic retransmission control in the mobile station 3 and the base station 4. ing. FIG. 2 is also used in this embodiment.

Next, the operation of this embodiment will be described with reference to FIG. 2, FIG. 6, and FIG. The assignment of the slot to the mobile device 3 is the same as in the first embodiment, and a description thereof will be omitted. Here, the mobile station 3 requests the base station 4 for uplink one-way communication in the slot # 1 of the uplink control channel,
The operation after the state where the base station 4 has allocated the information channels # 1 to # 3 to the mobile device 3 will be described.

As shown in FIG. 6, the mobile station 3, which is the burst data transmitting side, includes in the user information the uplink slot # 1 of the control channel of the frame in which the burst data is to be transmitted.
If an error is not detected (success) in FIG. 2 (“success”), “0” is added. The transmission burst data is formed and transmitted to the base station 4 which is the receiving side device, using the slot of the allocated information channel.

Next, the processing operation of the mobile device 3 as the transmitting device and the base station 4 as the receiving device in the present embodiment will be described using the sequence shown in FIG. If the mobile station 3 succeeds in receiving the control channel in the frame, that is, if no error is detected in the information received in the control channel, the mobile station 3 transmits all the transmission burst data (1, 2, 3) transmitted in the frame. ) Is added to the control channel reception correct / failure information portion of “0” indicating reception success, and transmission is performed using an individually allocated slot (TDMA frame ○ 1 in FIG. 7). The base station 4 that has received the burst data extracts the control channel reception correct / failure information portion in which no error was detected, and if all are “0”, the burst data received in the previous frame of the frame is regarded as normal reception and the data is received. The burst data (1, 2, 2) transmitted to the assembling processing unit (not shown) and received in the frame
3) is newly stored in the storage unit (not shown).

Next, when the base station 4 normally receives the burst data in the frame, that is, does not detect an error, the base station 4 transmits a burst data reception success signal using the downlink slot # 1 of the control channel of the next frame. Transmit (TDMA frame # 2 in FIG. 7). The mobile station 3 that has received the burst data reception success signal continuously uses the slots # 1 to # 3 of the information channel of the frame to transmit the three burst data (4, (5, 6) is transmitted. The base station 4 receives the burst data in the previous frame in the same manner as the burst data reception in the previous frame, and extracts the control channel reception correct / incorrect information of the burst data in which no error is detected. The stored burst data (1,
2, 3) are transferred to a data assembly processing unit (not shown), and the received burst data (4, 5, 6) is stored in a storage unit (not shown).

Further, the base station 4 transmits a burst data reception success signal using the downlink slot # 1 of the control channel of the next frame. If the mobile station 3 fails to receive the control channel for transmitting the burst data reception success signal (the X mark in the TDMA frame ○ 3 in FIG. 7), the mobile station 3 re-transmits the three burst data transmitted in the previous frame. (4, 5, 6) is transmitted by changing the control channel reception correctness information portion to be added to the burst data to "1". The base station 4 that has received the burst data extracts the control channel reception correctness information. If at least one is “1”, the base station 4 discards the burst data received and stored in the previous frame and discards it in the current frame. The received burst data is stored in a storage unit (not shown).

Further, the base station 4 transmits a burst data reception success signal again in the downlink slot # 1 of the control channel of the next frame, and the mobile station 3 having received the burst data reception success signal continues to transmit the information channel of the frame. "0" is added to the control channel reception correctness information
The three burst data (7, 8, 9) marked with are transmitted. (TDMA frame # 4 in FIG. 7) The base station 4 that has received the burst data extracts the control channel reception right / wrong information portion, and if all are "0", receives and stores the previous frame of the frame. Burst data (4,
5, 6) are transmitted normally to a data assembling unit (not shown), and the burst data (7, 8, 9) received in the frame is newly stored in a storage unit (not shown).

Further, the base station 4 transmits the burst data reception success signal in the downlink slot # 1 of the control channel of the next frame. Hereinafter, the same operation is continued until the end of the burst data.

When retransmitting burst data using the automatic retransmission control method shown in the present embodiment, it is possible to retransmit only burst data in which an error has occurred, or to transmit data in slots subsequent to the burst data in which an error has occurred. It is also possible to retransmit all of the burst data obtained.

In the case where a device for retransmitting only erroneous burst data is used, and in the present embodiment, the same burst data is transmitted a plurality of times when the control channel is continuously erroneous, the same burst data is transmitted. It is also possible to sequentially exclude the burst data that was received normally within the retransmission target from the retransmission target, and at the stage where the burst data indicating that the control channel has been received normally is received, it is possible to request retransmission only for the burst data that has failed to be received so far. is there.

According to this embodiment, by adding the success / failure information of the feedback channel to the burst data received on the information channel, it is possible to determine whether the received burst data is a burst data transmission by retransmission. Therefore, it is possible to easily control the order of the received data in the receiving device.

Embodiment 4 FIG. 8 is a sequence diagram showing another embodiment of the automatic retransmission control method according to the present invention, showing a sequence between the base station 4 and the mobile station 3. 3 shows a flow of an automatic retransmission request and retransmission process in the mobile device 3 and the base station 4. Next, the operation of the present embodiment will be described with reference to FIG. The assignment of the slot to the mobile device 3 is the same as in the first embodiment, and a description thereof will be omitted. Here, the mobile station 3 issues a request for uplink one-way communication to the base station 4 in the slot # 1 of the uplink control channel, and the base station 4 allocates information channels # 1 to # 3 to the mobile station 3. The operation after the state will be described.

As shown in FIG. 8, the mobile station 3, which is the transmitting side apparatus, transmits burst data (1, 2, 3) with control channel reception right / wrong information "0" as in the third embodiment. . When the base station 4 receiving the burst data has no error in the burst data received in the frame,
A burst data reception success signal is transmitted using the downlink control channel. On the other hand, when the base station 4 detects an error in the burst data 4 among the received burst data (4, 5, 6), the base station 4 uses the downlink control channel to
When “0” (# 0 in the figure) representing the frame and burst data in which an error has occurred are “4”, the slot position of the burst data “4” is represented (100).
Is transmitted to the mobile device 3. Upon detecting an error in the control channel including the burst data reception success signal and the burst data reception failure signal, the mobile station 3 transmits the burst data (7, 8, 9) subsequent to the burst data transmitted up to the previous frame. Data control channel reception correctness information is set to “1” and transmitted using the information channel (○ 3 in FIG. 8).

The base station 4 that has received the burst data of which the control channel reception correctness information is "1" transmits a burst data reception failure signal on the control channel of the next frame regardless of the success / failure of the burst data reception of the frame. I do. At this time, the burst data reception failure signal includes the slot position of “0” (# 0 in the figure) representing the frame immediately before transmitted on the control channel of the previous frame and the slot position of the burst data “4” in which the error has occurred. Express (100)
Is transmitted again, and “1” representing the previous frame is transmitted.
(# 1 in the figure) and the burst data in which the error occurred
In the case of “8”, the mobile station 3 which has received the burst data reception failure signal adds (010) representing the slot position of the burst data “8” and transmits the burst data. Burst data (4,
8, 10) to which "0" is added as control channel reception correctness information, and the information is transmitted to the base station 4 using the information channel.

In this embodiment, a device for retransmitting only erroneous burst data has been described. However, by retransmitting only erroneous frames, the amount of information added to the burst data reception failure signal can be reduced.

According to this embodiment, even when an error over a plurality of frames occurs in the information channel and the control channel (feedback channel), it is possible to easily retransmit only the burst data in which the error has occurred due to the automatic retransmission request. This has the effect.

Embodiment 5 FIG. 9 is a sequence diagram showing another embodiment of the automatic retransmission control method according to the present invention, and shows a sequence based on slot allocation change. Next, the operation of the present embodiment will be described with reference to FIG.

In FIG. 9, as in the second embodiment, mobile station 3 transmits burst data in a slot to which an information channel is allocated. When detecting an error in the received burst data, the base station 4 transmits a burst data reception failure signal to which information indicating the position of the burst data in which the error is detected is added. The mobile station 3 that has received the burst data reception failure signal retransmits transmission burst data subsequent to the burst data. If an error occurs in burst data in adjacent frames, a large amount of transmission burst data is accumulated in the mobile station 3 on the transmission side.

In this case, the base station 4 allocates additional slots to the mobile station 3 which receives a smaller number of slots than the number of slots allocated to the information channel and generates a burst data reception failure signal frequently. To increase the number of transmission burst data per frame from the mobile device 3. Further, when the transmission burst data cannot be detected in the allocated slot or when a predetermined time has elapsed, the base station 4 sends a notification to the effect that the slot allocation of the mobile station 3 is to be decreased by the control channel. Notify machine 3. As a result, the mobile station 3 stops transmission in the designated slot, and resumes transmission in the normal number of allocated slots.

The above-mentioned slot assignment is performed by the mobile station 3
The transmission delay of the transmission burst data from the mobile device 3 can be reduced by changing the number of times of transmission of the arrival transmission burst data or the burst data reception failure signal from the mobile station 3. However, when the transmitting apparatus is the base station 4, it is necessary to send a slot assignment change request from the mobile station 3 to the base station.

According to this embodiment, the slot assignment can be changed according to the increase or decrease of the retransmission burst data generated in response to the transmission error of the wireless communication channel, so that the transmission delay and the throughput performance are improved. .

[0067]

According to the first aspect of the present invention, a burst data reception success signal or a burst data reception failure signal required for controlling a retransmission request of an information channel in a control channel in which a receiving device has higher error correction capability than an information channel. Is performed, the probability that the reception of a burst data reception success signal or a burst data reception failure signal fails to be received is reduced, and an effect is obtained that the throughput is improved.

Further, according to the second invention, the receiving side apparatus detects an error in each received burst data in units of TDMA frames, and detects a TDMA corresponding to the burst data in which an error has occurred.
Since the slot position of the slot is detected, information that can express the slot position is added to the reception failure signal in units of TDMA frames, and transmission is performed on the feedback channel of the TDMA frame after a predetermined time, transmission is performed on the feedback channel. This has the effect of reducing the amount of information such as sequence numbers and the amount of processing for retransmission.

According to the third aspect of the present invention, an automatic retransmission request can be made in units of TDMA frames and retransmission can be performed in units of TDMA frames, so that there is no need to use a sequence number or the number of standings, and transmission is performed using a feedback channel. And the amount of information such as sequence numbers to be performed, and Stop & Wait in units of TDMA frames.
There is an effect that the ARQ scheme can be easily realized.

According to the fourth aspect of the present invention, the reception success / failure information of the feedback channel is added to the burst data received on the information channel to determine whether the received burst data is a burst data transmission by retransmission. Since the determination can be made, there is an effect that the processing of the received data in the receiving device can be easily performed.

Further, according to the fifth aspect, the frame number and slot position of the burst data in which the reception side device has detected an error are added to the reception failure signal to notify the transmission side device,
Since the transmitting side apparatus retransmits the burst data specified by the frame number and the slot position, even if an error occurs over a plurality of frames in the information channel and the control channel (feedback channel), the burst data is transmitted by the automatic retransmission request. This makes it possible to easily retransmit the data.

Further, according to the sixth aspect, the slot allocation is changed in accordance with the increase or decrease of the retransmission burst data generated in response to the transmission error of the radio communication channel, so that the transmission delay and the throughput performance are improved. To play.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an embodiment of a communication system including an automatic retransmission control method according to the present invention.

FIG. 2 shows a TD used by the automatic retransmission control method according to the present invention.
FIG. 1 is a frame configuration diagram illustrating an embodiment of a configuration of a frame of an MA system.

FIG. 3 shows a base station 4 using the frame configuration shown in FIG.
FIG. 7 is a sequence diagram showing an operation sequence when communication between the mobile device 3 and the mobile device 3 is performed.

FIG. 4 is a frame configuration diagram showing another embodiment of the automatic retransmission control method according to the present invention.

FIG. 5 is a sequence diagram illustrating an operation sequence when transmission is performed using the frame illustrated in FIG. 4;

FIG. 6 is a transmission burst data configuration diagram showing a configuration of transmission burst data showing another embodiment of the burst data transmitted on the information channel in the present invention.

FIG. 7 is a sequence diagram showing a sequence when communication is performed between the mobile station 3 and the base station 4 using the transmission burst data shown in FIG.

FIG. 8 is a sequence diagram showing another embodiment of the automatic retransmission control method according to the present invention.

FIG. 9 is a sequence diagram showing another embodiment of the automatic retransmission control method according to the present invention.

FIG. 10 is an explanatory diagram showing an automatic retransmission request method in a conventional example.

FIG. 11 is a system configuration diagram in a conventional example.

FIG. 12 is a sequence diagram showing a retransmission procedure of an automatic retransmission request method in a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base station control device 2 wireless zone 3 mobile station 4 base station 10 transmitting-side wireless communication device 11 communication control unit 12 encoding unit 13 buffer memory 14 transmitting unit 15 receiving unit 16 switch 17 antenna 20 receiving-side wireless communication device 21 communication Control unit 22 Encoding unit 23 Buffer memory 24 Transmitting unit 25 Receiving unit 26 Changeover switch 27 Antenna

Continuation of the front page (56) References JP-A-7-245600 (JP, A) JP-A-7-74735 (JP, A) JP-A-7-336774 (JP, A) JP-A-9-181759 (JP) , A) JP-A-8-237735 (JP, A) JP-A-7-250370 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04B 7/24 H04L 1/00 H04J 3/00

Claims (6)

(57) [Claims] At least one base station that manages a wireless zone, a base station controller that integrally manages the base station,
An information channel for transmitting information for a user, and TDMA (Time Division Mul) of the information channel.
at least one of which is accessed using a demand-assigned TDMA system that performs assignment with the base station on demand via a wireless communication channel that includes a control channel that assigns a slot of “type access”.
One mobile station, and used in a wireless communication system configured from the base station or the transmitting side apparatus that transmits burst data, the mobile station that is the receiving side apparatus that receives the burst data from the mobile station or The base station uses the control channel as a feedback channel for transmitting a burst data reception success signal (Ack) and a burst data reception failure signal (Nack), and a burst data reception success signal on the control channel. The transmission of the burst data reception failure signal includes means for adding an error correction code that takes a codeword length for the information length longer than the error correction code applied to the burst data transmitted on the information channel. Characteristic automatic retransmission control method. 2. The receiving apparatus includes error detecting means for detecting an error for each burst data received from the transmitting apparatus in a TDMA frame unit, and a TDMA slot position corresponding to the burst data in which the error is detected. And a slot position detecting means for detecting the error, and adding the slot position to the reception failure signal in units of TDMA frames for each of the transmitting-side apparatuses that have transmitted the burst data in which the error has been detected, and after a predetermined time, 2. The automatic retransmission control method according to claim 1, further comprising: transmission means for transmitting using a control channel that is a feedback channel in the frame. 3. A burst data reading means for reading, from a storage unit, burst data subsequent to burst data corresponding to a slot position added to a reception failure signal received on a control channel which is a feedback channel from a receiving device. And retransmitting means for retransmitting the burst data read from the storage section by the burst data reading means in a TDMA frame after a predetermined time in order from the first slot in TDMA frame units. 3. The automatic retransmission control method according to claim 2, wherein: 4. A transmission-side apparatus, comprising: an error detection unit configured to detect an error in received information due to a control channel that is a feedback channel from the receiving-side apparatus; Transmitting means for transmitting information indicating success or failure together with burst data on an information channel in a TDMA frame after a predetermined time, wherein the transmitting apparatus detects an error in the control channel, All the previously transmitted burst data is re-used by using the frame in which the delivery confirmation is to be obtained by the burst data reception success signal (Ack) and the burst data reception failure signal (Nack) scheduled to be received on the control channel. The automatic retransmission control method according to claim 1, wherein the transmission is performed. 5. The receiving device performs error detection on each burst data received from the transmitting device on a TDMA frame basis, and a slot position of a TDMA slot corresponding to the burst data in which the error has occurred. And a slot number detecting means for detecting a frame number for identifying the frame and the slot position for each transmitting apparatus transmitting the erroneous burst data to the reception failure signal for each TDMA frame, and Response means for transmitting on a control channel that is a feedback channel in a TDMA frame after a predetermined time, wherein the transmitting device transmits the burst data specified by the information expressing the frame number and the slot position. Burst data reading means for reading from the storage unit, 2. The automatic retransmission control method according to claim 1, further comprising retransmission means for retransmitting the designated burst data in order from the front of the one or more TDMA slots. 6. A number-of-slots calculating means for calculating the number of slots required for retransmission of the burst data and transmission of untransmitted burst data when the receiving apparatus detects an error in one or more received burst data. When the receiving apparatus is a mobile station, the apparatus further comprises slot number requesting means for requesting the calculated number of slots together with a reception failure signal on a control channel, and when the receiving apparatus is a base station, TDMA slot assignment changing means for changing the assignment of TDMA slots in accordance with the number of slots, and an assignment slot for notifying the assignment of the assignment slot to the mobile station as the transmitting side device using the control channel together with the reception failure signal. 2. The automatic retransmission control method according to claim 1, further comprising a change notification unit.