WO2010046956A1 - 適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 - Google Patents
適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 Download PDFInfo
- Publication number
- WO2010046956A1 WO2010046956A1 PCT/JP2008/003032 JP2008003032W WO2010046956A1 WO 2010046956 A1 WO2010046956 A1 WO 2010046956A1 JP 2008003032 W JP2008003032 W JP 2008003032W WO 2010046956 A1 WO2010046956 A1 WO 2010046956A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- unit
- retransmission
- packet
- new
- decoding
- Prior art date
Links
- 238000004891 communication Methods 0.000 title claims abstract description 167
- 238000000034 method Methods 0.000 title claims abstract description 101
- 230000003044 adaptive effect Effects 0.000 title 1
- 230000005540 biological transmission Effects 0.000 claims description 186
- 238000012545 processing Methods 0.000 claims description 37
- 239000000284 extract Substances 0.000 claims description 12
- 238000012790 confirmation Methods 0.000 claims description 10
- 238000002360 preparation method Methods 0.000 claims description 10
- 230000003139 buffering effect Effects 0.000 claims description 9
- 102100038192 Serine/threonine-protein kinase TBK1 Human genes 0.000 description 32
- 230000008569 process Effects 0.000 description 12
- 238000000926 separation method Methods 0.000 description 12
- 102100036409 Activated CDC42 kinase 1 Human genes 0.000 description 10
- 238000010586 diagram Methods 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 238000003786 synthesis reaction Methods 0.000 description 4
- 230000002194 synthesizing effect Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000003111 delayed effect Effects 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 101100545229 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) ZDS2 gene Proteins 0.000 description 1
- 101100167209 Ustilago maydis (strain 521 / FGSC 9021) CHS8 gene Proteins 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 238000010187 selection method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1867—Arrangements specially adapted for the transmitter end
- H04L1/1887—Scheduling and prioritising arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
- H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
- H04L1/0026—Transmission of channel quality indication
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
- H04L1/0002—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate
- H04L1/0003—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate by switching between different modulation schemes
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
- H04L1/0009—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the channel coding
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0056—Systems characterized by the type of code used
- H04L1/0071—Use of interleaving
Definitions
- the present invention relates to a technique for retransmitting transmission information based on delivery confirmation information returned from a receiving apparatus to a transmitting apparatus in packet communication technology.
- the packet communication technology include E-UTRA (Evolved Universal Terrestrial Radio Access) communication technology that is being studied as a next-generation mobile phone communication standard.
- New mobile phone communication standards such as LTE (Long Term Evolution), which is being standardized by the standardization organization 3GPP (3rd Generation Partnership Project), packets for enabling high-speed communication on mobile terminals Communication technology has been developed.
- LTE Long Term Evolution
- 3GPP 3rd Generation Partnership Project
- a receiving apparatus receives communication information while detecting an error based on an error correction code added to a communication packet by a transmitting apparatus. Then, the reception device returns a success or failure of reception of the communication packet as ACK (positive delivery confirmation) or NAK (negative delivery confirmation) to the transmission device. The transmitting apparatus retransmits the transmission information when the receiving apparatus returns NAK or when the delivery confirmation cannot be received by the time when a reasonable time has elapsed after transmitting the packet.
- ACK positive delivery confirmation
- NAK negative delivery confirmation
- HARQ hybrid automatic repeat request
- LTE Long Term Evolution
- LTE layer 1 protocol layer
- data that failed to be decoded in the receiving apparatus is decoded without being discarded and combined with retransmission data, and then retransmitted on the transmitting apparatus side.
- a pattern is determined.
- the data that has failed to be received is not discarded but is decoded in combination with the retransmission data.
- HARQ a chase combining (CC) method and an incremental redundancy (IR) method are known.
- the transmission apparatus retransmits a copy of a packet encoded in the same way as the first transmitted packet at the time of retransmission.
- the receiving apparatus combines the packet that failed to be received first and the retransmitted packet, and performs decoding on the entire combined signal.
- SNR Signal to Noise Ratio
- the transmission apparatus does not transmit a simple repetition of the entire packet encoded in the same way as the packet transmitted first, but incrementally transmits additional redundant information.
- the receiving apparatus combines the redundant information contained in the packet that failed to be received first and the packet that was incrementally retransmitted, and performs decoding on the entire combined signal.
- redundant information used for decoding increases, SNR increases cumulatively, decoding accuracy in the receiving apparatus improves, and packet errors can be reduced.
- a HARQ scheme based on the N-channel stop-and-wait protocol has been proposed based on the above-described two schemes.
- This method is based on an operation in which a transmitting apparatus transmits a frame and then waits for an ACK from the corresponding receiving apparatus to transmit the next frame.
- the stop-and-wait mechanism is simple, but the transmission efficiency is reduced because the transmission device needs to wait for approval from the reception device.
- N-channel stop-and-wait processing when one HARQ process is waiting for delivery confirmation from the receiving device, another HARQ process can use that channel to transmit other data.
- This HARQ process is widely used in many standard communication standards such as IEEE 802.16e and LTE.
- this HARQ scheme is called a “full HARQ scheme” in the sense that the channel is completely occupied.
- Non-Complete Puncture Non-Complete Puncture
- the transmitting device makes a hole in a part of the frame configuration bit portion to which the parity bit portion of the new packet should be assigned in the channel to which the newly incoming packet is assigned. Insert, ie puncture.
- the new packet and the retransmission packet are independently encoded.
- the receiving apparatus separates the new packet and the retransmission packet mixed on one channel and decodes them individually.
- the receiving apparatus performs packet restoration processing based on the CC method or the IR method for the retransmitted packet.
- the retransmission packet is punctured to the parity bit part on the same channel frame as the new incoming packet, so that channel resources are not wasted and the overall throughput can be significantly improved.
- Non-Patent Document 2 In order to solve this problem, we recently proposed a G (Group based) -HARQ scheme in Non-Patent Document 2 below.
- the transmission apparatus groups retransmission data together with new data in the information portion (payload) instead of the parity bit portion of the new packet in a channel to which a newly incoming packet is assigned.
- the new data and the retransmission data are newly encoded together, and the parity bit is newly calculated and transmitted as a new packet.
- the receiving apparatus separates the new packet and the retransmission packet by decoding the packet.
- the receiving apparatus performs packet restoration processing based on the CC method or the IR method for the retransmitted packet.
- retransmission packets are grouped in the information bit part on the same channel frame as a new incoming packet, so that in addition to not wasting channel resources, data packets are delivered at a high coding rate. It is advantageous when However, when the coding rate is low, the NCP-HARQ scheme is more advantageous because G-HARQ compresses the information bit part of the new incoming packet.
- the full HARQ scheme is more advantageous than the NCP-HARQ scheme and G-HARQ scheme, which have a large retransmission processing delay.
- the full HARQ scheme, the NCP-HARQ scheme, and the G-HARQ scheme have problems in that they have advantages and disadvantages depending on transmission conditions such as a coding rate and a retransmission rate.
- Wu Jianming, W. Tong, and J. Li “Non-complete puncture based re-transmission for HARQ”, C50-20011105-025, 3GPP2 TSG-C WG5, November 5, 2001
- the challenge is to design a HARQ system that can operate properly in all channel environments.
- retransmission of packet transmission is performed in order to cause the receiving device to decode in combination with the retransmitted packet without discarding the packet. Assuming a transmission device that controls the above, the following configuration is provided.
- the block generation unit generates a block having a predetermined size from the information bits to be transmitted.
- the retransmission buffer unit temporarily holds a block of information bits generated by the block generation unit in preparation for retransmission.
- the new part acquisition unit acquires a new part to be transmitted from the block generated by the block generation unit.
- the retransmission part acquisition unit acquires a retransmission part to be transmitted from the block for retransmission held in the retransmission buffer unit.
- the first encoding unit generates a new packet from the new part acquired from the new part acquisition unit, generates a retransmission packet from the retransmission part acquired from the retransmission part acquisition unit, and each of the new packet and the retransmission packet Assign to individual communication channels, and output individual communication channel data obtained as a result.
- the second encoding unit assigns a packet obtained by mixing the new part acquired from the new part acquisition unit and the retransmission part output from the retransmission part acquisition unit to the communication channel, and communication channel data obtained as a result Is output.
- the modulation unit modulates communication channel data output from the first encoding unit or the second encoding unit.
- the transmission processing unit transmits the output of the modulation unit.
- the encoding scheme switching unit switches the operation of the first encoding unit or the second encoding unit.
- the transmission control unit controls the coding scheme switching unit based on information indicating the communication quality of the communication channel in the receiving device. For example, the transmission control unit periodically receives a channel quality indicator indicating the communication quality of the communication channel from the receiving device as information indicating the communication quality of the communication channel in the receiving device, and uses the communication channel based on the channel quality indicator.
- the coding method switching unit is made to select the first coding unit, and in other cases, the coding method switching unit Two encoding units can be selected.
- the transmission control unit periodically receives movement speed information indicating the movement speed of the mobile terminal device on which the receiving apparatus is mounted as information indicating the communication quality of the communication channel in the receiving apparatus,
- the encoding method switching unit is made to select the first encoding unit, and in other cases, the encoding method switching unit is made to select the second encoding unit.
- the second encoding unit generates a new packet from the new part acquired from the new part acquisition unit, assigns the new packet to the communication channel, and in the communication channel, Inserting the information bits of the retransmission part output from the retransmission part acquisition unit into the part of the bit position where the parity bit part of the new packet is to be assigned, with delayed assignment to the part of the bit position of the new packet,
- the third encoding unit that outputs the communication channel data obtained as a result, the new part acquired from the new part acquisition unit, and the retransmission part output from the retransmission part acquisition unit so as to reduce the allocation of the new part
- assign the packet to a communication channel assign the packet to a communication channel, and obtain the resulting communication channel data.
- a coding scheme switching unit that switches operations of the first coding unit, the third coding unit, or the fourth coding unit, and a transmission control unit. Calculates the coding rate representing the coding efficiency in the communication channel, and when the second coding unit is selected, if the coding rate is larger than a predetermined threshold, the coding method switching unit.
- the fourth encoding unit can be selected, and in other cases, the encoding method switching unit can be configured to select the third encoding unit.
- the transmission control unit for example, includes first selection information indicating which of the first encoding unit and the second encoding unit is selected by the encoding method switching unit, The receiving apparatus can be notified using a control channel corresponding to the communication channel.
- the transmission control unit for example, displays the second selection information indicating which of the third encoding unit and the fourth encoding unit is selected by the encoding method switching unit, and the control channel corresponding to the communication channel. Can be used to notify the receiving device.
- the reception confirmation information indicating the success / failure of the received packet is returned to the transmission device, and the reception packet that has failed in decoding is received in combination with the received packet retransmitted from the transmission device without being discarded.
- the following configuration is provided.
- the reception processing unit receives a reception signal.
- the demodulator demodulates the received packet from the communication channel that constitutes the received signal.
- the retransmission buffer unit temporarily holds the received packet in preparation for combining with the retransmission packet.
- the first decoding unit by identifying the communication channel of the received packet, sorts the received packet into a new packet in which the new part is stored and a retransmission packet in which the retransmission part is stored.
- the extracted information bits are extracted and output, and the information bits of the retransmission part are extracted from the retransmission packet and combined with the reception packet that has failed in reception held in the retransmission buffer unit. Extracts information bits from the packet and outputs them.
- the second decoding unit extracts the new part and the retransmission part from the received packet, extracts and outputs the information bits of the new part, extracts the information bits of the retransmission part, and receives the information held in the retransmission buffer unit.
- the received packet is restored by combining with the failed received packet, and information bits are extracted from the received packet and output.
- the decoding scheme switching unit switches the operation of the first decoding unit or the second decoding unit.
- the reception control unit controls the decoding scheme switching unit based on information indicating the communication quality of the communication channel.
- the reception control unit corresponds to the communication channel with the first selection information indicating which of the first decoding unit and the second decoding unit should be selected as information indicating the communication quality of the communication channel.
- the decoding method switching unit can be configured to be received based on the first selection information received from the transmission device using the control channel.
- the second decoding unit separates the new packet storing the new part from the received packet and the retransmission packet storing the retransmission part from the received packet.
- the information bits are extracted and output, the information bits of the retransmission part are extracted from the retransmission packet, and the received packet is restored by combining it with the received packet that has failed in reception held in the retransmission buffer unit.
- the third decoding unit that extracts and outputs information bits from the received packet, and the received packet held in the retransmission buffer unit that failed to receive, or the new part or retransmission part that was extracted in advance,
- the new part and the retransmission part are separated from the information bits, the information bits of the new part are extracted and output, and the information bits of the retransmission part are extracted.
- the received packet held in the retransmission buffer is unsuccessfully received, or the received packet is restored by combining with the previously extracted new part or retransmission part, and information bits are extracted from the received packet and output.
- the decoding unit switching unit switches the operation of the first decoding unit, the third decoding unit, or the fourth decoding unit, and the reception control unit performs encoding in the communication channel.
- the decoding scheme switching unit selects the fourth decoding unit, In other cases, the decoding method switching unit can be configured to select the third decoding unit.
- the reception control unit calculates, for example, a coding rate representing the coding efficiency in the communication channel from the modulation code scheme of the communication currently being performed on the communication channel. Can be configured to obtain.
- the receiving apparatus is a receiver.
- the reception control unit should select, for example, the third decoding unit or the fourth decoding unit as the coding rate representing the coding efficiency in the communication channel.
- movement flowchart which shows the HARQ system switching process by the control channel transmission / reception part 111 in a downlink side transmitter and an uplink side receiver.
- FIG. 10 is an operation explanatory diagram of the G-HARQ decoding unit 207.
- FIG. 1 is a configuration diagram of an embodiment of a transmission device of a packet transmission / reception system.
- FIG. 2 is a configuration diagram of the embodiment of the receiving apparatus.
- the packet transmission / reception system is configured as a communication system between a wireless mobile terminal (such as a mobile phone terminal) and a wireless base station, for example.
- the transmission apparatus of FIG. 1 is installed on both the downlink side of the radio base station and the uplink side of the radio mobile terminal.
- 2 is installed on both the uplink side of the radio base station and the downlink side of the radio mobile terminal.
- the packet receiving system can be realized as an E-UTRA (Evolved Universal Terrestrial Radio Access) system in the LTE communication standard that is being standardized in 3GPP.
- E-UTRA Evolved Universal Terrestrial Radio Access
- HARQ scheme switching unit 105 decoding scheme switching unit
- full HARQ encoding unit 106 First encoding unit
- NCP-HARQ encoding unit 107 third encoding unit
- G-HARQ encoding unit 108 first encoding unit constituting a partial HARQ encoding unit (second encoding unit) 4 encoding unit
- modulation unit 109 a transmission processing unit 110
- control channel transmission / reception unit 111 transmission control unit
- the full HARQ encoding unit 106 further includes a new packet encoding unit 106-1, a retransmission packet encoding unit 106-2, and a channel allocation unit 106-3.
- the NCP-HARQ encoding unit 107 includes a new packet encoding unit 107-1 and a puncturing unit 107-2.
- the G-HARQ encoding unit 108 includes a packet combining unit 108-1 and a packet encoding unit 108-2.
- the control channel transmission / reception unit 111 can be the same as the control channel transmission / reception unit 111 on the transmission apparatus side shown in FIG.
- Full HARQ decoding section 205 further includes retransmission channel separation section 205-1, decoding section 205-2, retransmission partial combining section 205-3, and decoding section 205-4.
- the NCP-HARQ decoding unit 206 includes a packet separation unit 206-1, a decoding unit 205-2 common to the above, a retransmission partial synthesis unit 205-3, and a decoding unit 205-4.
- the G-HARQ decoding unit 207 includes a packet combining unit 207-1, a decoding unit 207-2, an output switching unit 207-3, a retransmission partial combining unit 207-4, a decoding unit 207-5, and an output switching unit 207-. 6 is composed.
- the full HARQ scheme, the NCP-HARQ scheme, and the G-HARQ scheme have the following advantages and disadvantages depending on transmission conditions such as a coding rate and a retransmission rate. Can be automatically switched.
- the full HARQ method is more advantageous than the NCP-HARQ method and the G-HARQ method having a large retransmission processing delay.
- Characteristic 2 The G-HARQ scheme is advantageous when data packets are delivered at a low coding rate with a low retransmission rate.
- Characteristic 3 When the retransmission rate of data packets is low and the data packets are delivered at a low coding rate, the NCP-HARQ scheme is advantageous.
- control channel transmission / reception unit 111 controls the HARQ scheme switching unit 105.
- the control channel transmission / reception unit 111 common to FIG. Controls the HARQ system switching unit 204 to realize automatic switching of the HARQ system.
- the NCP-HARQ method and the G-HARQ method are referred to as “partial HARQ method” in the sense that the channel of a new incoming packet is partially used with respect to the full HARQ method.
- a channel quality indicator (CQI: Channel Quality) notified from the radio mobile terminal to the radio base station is used.
- CQI Channel Quality
- MCS modulation code scheme
- CQI notification (CQI report) CR is periodically sent from each wireless mobile terminal to the wireless base station at a certain interval such as CR0, CR1,..., CR8. Shall be notified.
- the MCS modulation code scheme
- MU used modulation code scheme
- MCS error the MCS error for MU1 is simply calculated as the difference in CR between the intervals separated by the MCS error interval corresponding to the processing delay as follows.
- the MCS1 error CR3-CR1
- MCS error interval is equal to the processing delay.
- MCS n (Error) CR n ⁇ CR nk (1)
- k is an index of processing delay.
- HARQ processing must be based on an instruction by a control signal transmitted on a control channel.
- an E-UTRA communication system is employed as the packet transmission / reception system
- the data format shown in FIG. 4 is employed. That is, first, as shown in FIG. 4 (a), one subframe is composed of, for example, two slots of 0.5 msec length obtained by dividing a radio frame of 10 msec (milliseconds) length into 20 # 0 to # 20. Is done. Then, as shown in FIG. 4B, an L1 control channel and a data channel are allocated in the subframe.
- a new packet or retransmission packet which is an information bit, is inserted into the data channel and transmitted.
- various control information that requires communication between the transmission apparatus and the reception apparatus is inserted and transmitted in accordance with the adopted HARQ scheme.
- the CQI notification timing for calculating the MCS error criterion for selecting the full HARQ scheme or the partial HARQ scheme is shown in FIG. 4 using, for example, an uplink control channel from the radio mobile terminal to the radio base station. Is reported in units of subframes (or slots) shown in FIG.
- a unit longer than the subframe unit shown in FIG. 4 (low speed reference of 10 to 20 msec to 50 msec)
- a long-term parameter such as a moving speed of the wireless mobile terminal is notified, and based on the long-term parameter, a selection can be made between a full HARQ scheme and a partial HARQ scheme.
- a high moving speed corresponds to the above-described MCS error being large
- a low moving speed corresponds to the above-described MCS error being small. Therefore, the moving speed information periodically notified from the wireless mobile terminal can be handled in the same manner as the MCS error.
- the HARQ switching point can be the timing of each segment of a 10 msec radio frame, or can be the timing of each segment of a radio frame.
- the full HARQ scheme selection bit may be configured to be inserted into the L1 control channel.
- the switching timing between the CQI report and the HARQ system changes relatively frequently as shown in FIG.
- the first scheme is a method using one bit of the L1 control channel.
- the second scheme is a method using 1 bit from the high layer control information as described above.
- any one of the six types of schemes indicated by the arrows in FIG. 6 can be selected as the HARQ scheme selection instruction scheme.
- the following selection instructions are more preferable.
- threshold 2 a predetermined threshold
- the block generation unit 101 generates a block of a predetermined size from information bits to be transmitted.
- the size of the block generated by the block generation unit 101 is equal to the amount of information bits that can be stored in one packet. That is, an ordinary packet transmitted by the transmission device includes information bits corresponding to one block.
- the retransmission buffer unit 102 temporarily holds the block of information bits generated by the block generation unit 101 in preparation for retransmission. Note that the retransmission buffer unit 102 may sequentially discard blocks that have been correctly decoded by the receiving device and need not be retransmitted.
- the MCS error is calculated by calculating the above-described equation (1) (step S701 in FIG. 7).
- the control channel transmission / reception unit 111 controls the HARQ scheme switching unit 105 to control the full HARQ encoding unit 106 to operate. (Step S703 in FIG. 7).
- FIG. 8 is an explanatory diagram of the full HARQ encoding method executed by the full HARQ encoding unit 106.
- the full HARQ method includes two main methods, the CC method and the IR method.
- the transmission apparatus retransmits a copy of a packet encoded in the same way as the packet transmitted first at the time of retransmission.
- the IR method as shown in FIG. 8 (b)
- the transmitting apparatus does not send a simple repetition of the entire packet encoded in the same way as the first transmitted packet at the time of retransmission. Redundant information is sent incrementally.
- the control channel transmission / reception unit 111 When operating the full HARQ encoding unit 106, the control channel transmission / reception unit 111 operates in accordance with a control signal received from the receiving apparatus via the control channel, and includes a new part and a retransmission part included in a newly transmitted packet. To the new part acquisition unit 103 and the retransmission part acquisition unit 104, respectively. Specifically, the control channel transmission / reception unit 111 first instructs the new part acquisition unit 103 to always transmit a new block generated by the block generation unit 101. In addition, when the number of received NAKs received from the receiving device reaches a predetermined number, the control channel transmission / reception unit 111 transmits the transmitted block held in the retransmission buffer unit 102 to the retransmission part acquisition unit 104.
- the retransmission portion acquisition unit 104 is instructed to retransmit a copy of the same block as the first transmission.
- the retransmission portion acquisition unit 104 is instructed to retransmit redundant information in addition to the block at the time of initial transmission.
- ACK and NAK are signals that are inserted, for example, from the above-described L1 control channel (see FIG. 4B) and received from, for example, a receiving device in a wireless mobile terminal. Indicates whether or not it occurred. These ACK and NAK are returned from the receiving device for each received packet. Therefore, the transmission apparatus needs to retransmit the transmission block included in the packet corresponding to the NAK. Therefore, when the control channel transmission / reception unit 111 in the transmission apparatus receives NAKs for a plurality of blocks, the control channel transmission / reception unit 111 retransmits the blocks corresponding to each NAK.
- the new part acquisition unit 103 When the full HARQ encoding unit 106 is operated, the new part acquisition unit 103 always acquires the entire block generated by the block generation unit 101 as a new part in accordance with an instruction from the control channel transmission / reception unit 111.
- the retransmission part acquisition unit 104 follows the instruction from the control channel transmission / reception unit 111, and when the number of received NAKs is less than the predetermined number, it is not the timing to retransmit the transmitted block.
- the block held in the unit 102 is not acquired as a retransmission part.
- retransmission part acquisition section 104 acquires information on the block of the packet corresponding to NAK among the blocks held in retransmission buffer section 102 as a retransmission part. .
- the CC method is adopted, a copy of the same block as that at the first transmission corresponding to the NAK is acquired as a retransmission part.
- the IR method is adopted, additional redundant information is acquired as a retransmission part for the block at the time of initial transmission corresponding to NAK.
- the new block acquired by the new partial acquisition unit 103 is input to the new packet encoding unit 106-1 in the full HARQ encoding unit 106 via the HARQ scheme switching unit 105. Also, when retransmission block information is acquired in retransmission part acquisition section 104, the information is sent to retransmission packet encoding section 106-2 in full HARQ encoding section 106 via HARQ scheme switching section 105. input.
- the new packet encoding unit 106-1 generates a new packet including the new block in the information bit part and the corresponding parity bit in the parity bit part.
- retransmission packet encoding section 106-2 generates a retransmission packet including the information bit part and the corresponding parity bit in the parity bit part.
- the channel allocation unit 106-3 allocates the generated new packet and retransmission packet to individual communication channels (individual subframes or slots in FIG. 4), and sends the resulting frame data to the modulation unit 109. Output.
- the new packet and the retransmission packet are respectively assigned to the individual communication channels and transmitted individually.
- This coding rate can be calculated based on the MCS level determined by the control channel transmission / reception unit 111 based on, for example, CQI periodically received from a wireless mobile terminal. For example, when an E-UTRA communication system is adopted as a packet transmission / reception system, the MCS level is obtained by using various modulation schemes and encoding schemes such as QPSK (quadrature phase shift keying), 16QAM (quadrature amplitude modulation), or 64QAM. It is an indicator to be determined. If the MCS level is determined, the coding rate (coding efficiency) can be determined.
- QPSK quadrature phase shift keying
- 16QAM quadrature amplitude modulation
- 64QAM
- control channel transmission / reception unit 111 determines in the above determination that the coding rate is equal to or less than the threshold value 2, the control channel transmission / reception unit 111 controls the HARQ scheme switching unit 105 to control the NCP-HARQ encoding unit 107 to operate. (Step S705 in FIG. 7).
- FIG. 9 is an explanatory diagram of the NCP-HARQ encoding method executed by the NCP-HARQ encoding unit 107.
- the transmission apparatus punctures a retransmission packet into a part of a frame configuration bit portion to which a parity bit portion of the new packet is to be assigned in a channel to which the new packet is assigned.
- an independent parity bit P is added to the information bit I of the new block in the new packet, and the retransmitted packet encoded independently is punctured.
- the control channel transmission / reception unit 111 When operating the NCP-HARQ encoding unit 107, the control channel transmission / reception unit 111 retransmits a new part included in a packet to be newly transmitted and a retransmission according to a control signal received from the receiving apparatus side via the control channel. The part is notified to the new part acquisition unit 103 and the retransmission part acquisition unit 104, respectively. Specifically, the control channel transmission / reception unit 111 first instructs the new part acquisition unit 103 to always transmit a new block generated by the block generation unit 101.
- the control channel transmission / reception unit 111 transmits the transmitted block held in the retransmission buffer unit 102 to the retransmission part acquisition unit 104.
- the retransmission portion acquisition unit 104 is instructed to retransmit a copy of the same block as the first transmission.
- the retransmission portion acquisition unit 104 is instructed to retransmit redundant information in addition to the block at the time of initial transmission.
- the new part acquisition unit 103 When the NCP-HARQ encoding unit 107 is operated, the new part acquisition unit 103 always acquires the entire block generated by the block generation unit 101 as a new part in accordance with an instruction from the control channel transmission / reception unit 111.
- the retransmission part acquisition unit 104 follows the instruction from the control channel transmission / reception unit 111, and when the number of received NAKs is less than the predetermined number, it is not the timing to retransmit the transmitted block.
- the block held in the unit 102 is not acquired as a retransmission part.
- retransmission part acquisition section 104 acquires information on the block of the packet corresponding to NAK among the blocks held in retransmission buffer section 102 as a retransmission part. .
- the CC method is adopted, a copy of the same block as that at the first transmission corresponding to the NAK is acquired as a retransmission part.
- the IR method is adopted, additional redundant information is acquired as a retransmission part for the block at the time of initial transmission corresponding to NAK.
- the new block acquired by the new partial acquisition unit 103 is input to the new packet encoding unit 107-1 in the NCP-HARQ encoding unit 107 via the HARQ scheme switching unit 105. Also, when retransmission block information is acquired in retransmission part acquisition section 104, the information is input to puncturing section 107-2 in NCP-HARQ encoding section 107 via HARQ scheme switching section 105. .
- the new packet encoding unit 106-1 generates a new packet including the new block in the information bit part and the corresponding parity bit in the parity bit part.
- the puncture unit 107-2 includes, in the channel to which the new packet is assigned, the information bits of the retransmission block output from the retransmission part acquisition unit 104 in a part of the frame configuration bit part to which the parity bit part of the new packet should be assigned Are sequentially punctured. As a result, the allocation of the parity bit part in the new packet is delayed by an amount corresponding to a part of the frame configuration bits being punctured.
- Puncturing section 107-2 outputs the combined packet (see “Retransmission” packet in FIG. 9) assigned to the frame of one communication channel obtained as a result to modulation section 109.
- the new packet and the retransmission packet are allocated to one communication channel in a form in which the retransmission packet is punctured to the parity bit part of the new packet. It will be transmitted as a unit.
- control channel transmission / reception unit 111 determines in step S704 of FIG. 7 that the coding rate is greater than the threshold value 2
- the control channel transmission / reception unit 111 controls the HARQ scheme switching unit 105 to control the G-HARQ encoding unit. 108 is operated (step S706 in FIG. 7).
- FIG. 10 is an explanatory diagram of the G-HARQ encoding method executed by the G-HARQ encoding unit 107.
- the transmission apparatus groups retransmission blocks together with new blocks in the information part (payload) instead of the parity bit part of the newly incoming packet.
- the new block and the retransmission block are newly encoded together, the parity bit is also newly calculated, and is transmitted as a new packet.
- the control channel transmission / reception unit 111 When operating the G-HARQ encoding unit 108, the control channel transmission / reception unit 111 retransmits a new part and a new part included in a packet to be newly transmitted according to a control signal received from the receiving apparatus side via the control channel. The part is notified to the new part acquisition unit 103 and the retransmission part acquisition unit 104, respectively. Specifically, the control channel transmission / reception unit 111 first generates the block generation unit 101 for the new part acquisition unit 103 when the number of received NAKs received from the receiving device side is less than a predetermined number. Instruct to always send the new block.
- the control channel transmission / reception unit 111 sends a new block generated by the block generation unit 101 to the new partial acquisition unit 103. Instruct to send part. Further, in that case, the control channel transmission / reception unit 111 instructs the retransmission part acquisition unit 104 to retransmit the transmitted block held in the retransmission buffer unit 102.
- the retransmission portion acquisition unit 104 is instructed to retransmit a copy of the same block as the first transmission.
- the IR method is adopted, as shown in FIG. 8 (b)
- the retransmission portion acquisition unit 104 is instructed to retransmit redundant information in addition to the block at the time of initial transmission.
- the new part acquisition unit 103 follows the instruction from the control channel transmission / reception unit 111, and when the number of received NAKs is less than the predetermined number, the block generation unit 101 The entire generated block is acquired as a new part. In addition, when the number of received NAKs reaches a predetermined number, the new part acquisition unit 104 acquires a part of the block generated by the block generation unit 101 as a new part.
- the retransmission part acquisition unit 104 follows the instruction from the control channel transmission / reception unit 111, and when the number of received NAKs is less than the predetermined number, it is not the timing to retransmit the transmitted block.
- the block held in the unit 102 is not acquired as a retransmission part.
- retransmission part acquisition section 104 acquires information on the block of the packet corresponding to NAK among the blocks held in retransmission buffer section 102 as a retransmission part. .
- the CC method is adopted, a copy of the same block as that at the first transmission corresponding to the NAK is acquired as a retransmission part.
- the IR method is adopted, additional redundant information is acquired as a retransmission part for the block at the time of initial transmission corresponding to NAK.
- the new block acquired by the new partial acquisition unit 103 is input to the puncturing unit 108-1 in the G-HARQ encoding unit 108 via the HARQ scheme switching unit 105. Also, when retransmission block information is acquired by retransmission part acquisition section 104, it is input to puncturing section 108-1 in G-HARQ encoding section 108 via HARQ scheme switching section 105.
- the packet combining unit 108-1 When the retransmission block is not output from the retransmission part acquisition unit 104, the packet combining unit 108-1 combines the information bit part only with the new block output from the new part acquisition unit 103. On the other hand, when the retransmission block is output from the retransmission part acquisition unit 104, the packet combining unit 108-1 and the new block output from the new part acquisition unit 103 and the retransmission block output from the retransmission part acquisition unit 104 Synthesizes the information bit part obtained by synthesizing with a predetermined synthesis pattern. As a result, when the retransmission block does not exist, the allocation of the information bit part in the new packet includes only the new block as in the normal packet. When the retransmission block exists, the new block information is retransmitted. Is reduced and delayed by the amount inserted.
- the packet encoding unit 108-2 generates the new packet including the new block and the retransmission block in the information bit part, and the corresponding parity bit in the parity bit part, and maps it to a frame of one communication channel Thereafter, the frame data is output to the modulation unit 109.
- the new packet and the retransmission packet are allocated to one communication channel in a form in which the retransmission packet is punctured to the information bit part of the new packet. It will be transmitted as a unit.
- the modulation unit 109 modulates frame data output from any of the full HARQ encoding unit 106, the NCP-HARQ encoding unit 107, or the G-HARQ encoding unit 108, and transmits a transmission processing unit. To 110.
- the transmission processing unit 110 performs predetermined wireless transmission processing (D / A conversion or the like) on the modulated frame data, and transmits the frame data via an antenna (not shown).
- FIG. 11 shows an example of the control operation for selecting the HARQ scheme executed by the control channel transmission / reception unit 111 when the receiving apparatus of FIG. 2 is installed in the downlink system of a wireless mobile terminal, for example. This will be described based on an operation flowchart.
- the reception processing unit 201 receives a signal transmitted from the transmitting apparatus in FIG. 1 in the radio base station via an antenna, and performs predetermined radio reception processing on the received signal. (A / D conversion, etc.) is executed.
- Demodulation section 202 demodulates the received packet from each communication channel constituting the received signal and outputs it to HARQ system switching section 204.
- the retransmission buffer unit 203 temporarily holds the received packet in preparation for combining with a retransmission packet received in the future. Then, when the received packet is input to retransmission partial combining sections 205-3 and 207-4 and packet combining section 207-1, retransmission buffer section 203 receives a past received packet corresponding to the retransmission portion included in the received packet. Output to them.
- the control channel transmission / reception unit 111 is a full HARQ scheme selection bit (FIG. 4 (FIG. 4)) periodically notified from the control channel transmission / reception unit 111 in the transmission apparatus of FIG. b)) is received (step S1101 in FIG. 11).
- the full HARQ scheme selection bit indicates that the full HARQ scheme is selected in the transmitter of FIG. 1 in the radio base station when the value is 1, and when the value is 0, the partial HARQ scheme selection bit is partially It shows that the HARQ method is selected.
- control channel transmission / reception unit 111 determines whether or not the value of the received full HARQ scheme selection bit is 1 (step S1102 in FIG. 11).
- the control channel transmission / reception unit 111 controls the HARQ scheme switching unit 204 to operate the full HARQ decoding unit 205 (see FIG. 11). Step S1103).
- the new packet and the retransmission packet are allocated to individual communication channels and transmitted individually.
- the received packet output from the demodulation unit 202 is input to the channel separation unit 205-1 in the full HARQ decoding unit 205 via the HARQ scheme switching unit 204. To do.
- the channel separation unit 205-1 distributes the new packet (normal packet) and the retransmission packet to the decoding unit 205-2 and the retransmission partial synthesis unit 205-3 by identifying the communication channel.
- the control channel transmission / reception unit 111 receives identification information indicating whether or not each communication channel is used as a channel of a retransmission packet, for example, using an L1 control channel from the transmission device, and uses this identification information as a channel separation unit. 205-1 is notified.
- the channel separation unit 205-1 sorts the new packet and the retransmission packet based on this identification information.
- the decoding unit 205-2 decodes the new packet input from the channel separation unit 205-1 and outputs the new information bit obtained as a result to a processing unit (not shown) in the subsequent stage.
- the decoding unit 205-2 calculates an error rate from the decoding result. For example, when the calculated error rate reaches a predetermined threshold value or more, the decoded information bit is not output and the new part is retransmitted.
- the control channel transmission / reception unit 111 is notified that it is necessary.
- retransmission partial combining section 205-3 first fails in reception when full HARQ encoding based on the CC scheme is performed in the transmission apparatus.
- the held past received packet and the retransmission packet input from the channel separation unit 205-1 are combined, and the combined result is output to the decoding unit 205-4.
- retransmission partial combining section 205-3 when full HARQ encoding based on the IR scheme is performed in the transmission apparatus, first fails in reception and retransmission buffer section
- the past received packet held in 203 and the incrementally retransmitted redundant information included in the retransmission packet are combined, and the combined result is output to the decoding unit 205-4.
- control channel transmission / reception unit 111 receives retransmission sequence information and other control information in the full HARQ scheme using, for example, the L1 control channel from the transmission apparatus, and notifies the retransmission partial combining unit 205-3 of these control information. To do.
- Retransmission partial combining section 205-3 combines retransmission packets based on these control information.
- the decoding unit 205-4 decodes the packet synthesized by retransmission, and outputs the restored information bits obtained as a result to a processing unit (not shown) in the subsequent stage.
- the decoding unit 205-4 calculates an error rate from the decoding result. For example, when the calculated error rate reaches a predetermined threshold value or more, the decoded information bit is not output and further retransmission is necessary.
- the control channel transmission / reception unit 111 is notified of this fact.
- step S1102 determines that the value of the full HARQ scheme selection bit is not 1 in step S1102 in FIG. 2
- This coding rate is currently applied to the communication of the corresponding communication channel based on MCS level information periodically received by the control channel transmission / reception unit 111 using, for example, the L1 control channel from the radio base station. It can be determined from the MCS.
- the control channel transmission / reception unit 111 controls the HARQ scheme switching unit 204 to operate the NCP-HARQ encoding unit 206 when the coding rate is equal to or less than the threshold 2 (step S1105 in FIG. 11). ).
- the new packet and the retransmission packet are transmitted in one communication channel in a form in which the retransmission packet is punctured in the parity bit part of the new packet. To be transmitted as a unit.
- the received packet output from the demodulation unit 202 is sent to the packet separation unit 206-1 in the NCP-HARQ decoding unit 206 via the HARQ scheme switching unit 204. To enter.
- the packet separation unit 206-1 separates the new packet and the retransmission packet from the packets received as a unit from one communication channel, and distributes them to the decoding unit 205-2 and the retransmission partial synthesis unit 205-3, respectively.
- the control channel transmission / reception unit 111 receives control information related to the puncture position and the like from the transmission device using, for example, the L1 control channel, and notifies the packet separation unit 206-1 of this control information.
- the packet separation unit 206-1 distributes the new packet and the retransmission packet based on this control information.
- the operation of the decoding unit 205-2 that decodes the new packet and the operations of the retransmission partial combining unit 205-3 and the decoding unit 205-4 that restore the past received packet from the retransmission packet are the same as the full HARQ decoding unit 205. Is the same as
- control channel transmission / reception unit 111 determines in step S1104 of FIG. 11 that the coding rate is greater than the threshold value 2
- the control channel transmission / reception unit 111 controls the HARQ scheme switching unit 204 to control the G-HARQ encoding unit. Control is performed to operate 207 (step S1106 in FIG. 11).
- the new packet and the retransmission packet are transmitted in one communication channel in a form in which the retransmission packet is punctured into the information bit part of the new packet. To be transmitted as a unit.
- the received packet output from the demodulation unit 202 is sent to the packet combining unit 207-1 in the G-HARQ decoding unit 207 via the HARQ scheme switching unit 204. And input to retransmission partial combining section 205-4.
- the packet combining unit 207-1 combines the retransmission part included in the received packet and a part of the past received packet output from the retransmission buffer unit 203.
- the packet combining unit 207-1 refers to a control signal for the G-HARQ scheme received by the control channel transmission / reception unit 111 from the transmission apparatus side, for example, via the L1 control channel.
- the packet combining unit 207-1 refers to the control signal and determines whether or not the received packet is a packet including a retransmission portion. When packet combining section 207-1 determines that the received packet does not contain a retransmission part, packet combining section 207-1 outputs the received packet as it is to decoding section 207-2.
- the packet combining unit 207-1 determines that the retransmission part is included in the received packet, a part of the past received packet output from the retransmission buffer unit 203 in the received packet or the output switching unit 207-6 The information bits output from are combined.
- the packet combining unit 207-1 acquires a part of the past received packet corresponding to the retransmission part included in the received packet from the retransmission buffer unit 203, and combines it with the received packet. .
- the packet combining unit 207-1 generates a combined packet by combining the information of the past received packet with the retransmission portion included in the received packet.
- the packet combining unit 207-1 fails in the first decoding process for a certain received packet including a new part and a retransmission part when a plurality of packets are continuously received in one reception. Even so, there may be a case where the decoding succeeds by synthesizing the successful information bits into the failed received packet again because the retransmission part of another received packet has been successfully decoded.
- the packet combining unit 207-1 combines the decoding result of the retransmission portion of the received packet output from the output switching unit 207-6 with the received packet at the second and subsequent decoding.
- the decoding result of the retransmission portion combined with the received packet after the second time is more accurate than the information of the past received packet combined at the time of the previous decoding or the decoding result of the retransmission portion.
- the synthesized packet is decoded more accurately.
- the packet synthesizing unit 207-1 outputs the synthesized packets generated at the first decoding and the second and subsequent decodings to the decoding unit 207-2.
- the decoding unit 207-2 decodes the received packet or the combined packet output from the packet combining unit 207-1.
- the decoding unit 207-2 performs decoding of the received packet using the redundant data portion of the received packet. Since the received packet does not include the retransmission part, the decoding result includes only the information bits of the new part.
- the decoding unit 207-2 When a combined packet is output from the packet combining unit 207-1, the decoding unit 207-2 performs not only the redundant data portion of the received packet, but also a part of the past received packet or the retransmission portion of another received packet. The decryption of the synthesized packet is executed using the result of the decryption. Then, decoding section 207-2 outputs the decoding result corresponding to the new part of the received packet to output switching section 207-3. The decoding unit 207-2 performs decoding using the decoding result of a part of the past received packet and the retransmission part of the other received packet, and thus obtains a decoding result with higher accuracy than when decoding by the received packet alone. be able to.
- the output switching unit 207-3 calculates an error rate from the decoding result in the decoding unit 207-2, and when the calculated error rate is equal to or greater than a predetermined threshold and the number of decoding iterations is less than the predetermined number, a new The partial decoding result is output only to retransmission partial combining section 207-4. Further, when the error rate is less than the predetermined threshold, the output switching unit 207-3 outputs the decoding result of the new portion to the retransmission partial combining unit 207-4, and particularly as the information bit of the new block The data is output to a subsequent processing unit (not shown).
- the output switching unit 207-3 outputs the decoding result of the new part to the retransmission partial combining unit 207-4 when the error rate is equal to or higher than a predetermined threshold and the number of decoding iterations reaches the predetermined number.
- the control channel transmitting / receiving unit 111 is notified that the new part needs to be retransmitted.
- retransmission part combining section 207-4 extracts the retransmission part contained in the received packet using the decoding result of the new part of the received packet, and combines it with the past received packet.
- the packet combining unit 207-1 refers to a control signal for the G-HARQ scheme received by the control channel transmission / reception unit 111 from the transmission apparatus side, for example, via the L1 control channel.
- retransmission part combining section 207-4 determines whether or not the received packet is a packet including the retransmission part. When retransmission part combining section 207-4 determines that the retransmission part is included in the received packet, it uses the decoding result of the new part output from output switching section 207-3 to extract the retransmission part from the received packet. To do. Then, retransmission part combining section 207-4 acquires a past received packet corresponding to the extracted retransmission part from retransmission buffer section 203, and combines the extracted retransmission part and the past received packet. As a result, retransmission partial combining section 207-4 generates a combined packet by combining the retransmitted portion of the new received packet with the past received packet.
- a new received packet may include retransmission parts related to a plurality of past received packets, in such a case, the retransmission part combining unit 207-4 receives each past received packet. For the corresponding retransmission part.
- the retransmission partial combining unit 207-4 may receive a plurality of packets in one reception. And even if the decoding of the retransmission part fails in the first decoding process for a certain received packet including the new part and the retransmission part, it succeeds because the decoding of the new part of other received packets succeeds. There are cases where decoding is successful by combining the information bits with the failed received packet again.
- the retransmission part combining unit 207-4 repeatedly extracts the retransmission part from the new received packet, Then, a synthesized packet is generated by synthesizing the retransmission portion more accurate than the previous decoding. Since the retransmission part extracted at the second and subsequent decoding is extracted using the decoding result of the new part with higher accuracy than the previous decoding, it is more accurate than the retransmission part extracted at the previous decoding. It will be.
- the decoding unit 207-5 decodes the combined packet output from the retransmission partial combining unit 207-4. That is, the decoding unit 207-5 performs decoding of the combined packet by using the past received packet in which there is an error and the retransmission part of the received packet. Then, the decoding unit 207-5 outputs the decoding result of the combined packet to the output switching unit 207-6.
- the decoding unit 207-5 performs decoding using information on the accurate retransmission part extracted using the decoding result of the new part, and therefore simply combines the retransmission part of the received packet with the past received packet and decodes it. It is possible to obtain a decoding result with higher accuracy than in the case of doing so.
- the output switching unit 207-6 calculates an error rate from the decoding result in the decoding unit 207-5. When the calculated error rate is equal to or greater than a predetermined threshold and the number of decoding iterations is less than the predetermined number, The decoding result corresponding to the retransmission part in the packet is output only to the packet combining unit 207-1. Further, when the error rate is less than the predetermined threshold, the output switching unit 207-6 outputs the decoded result of the combined packet to a subsequent processing unit (not shown).
- the output switching unit 207-6 determines that further retransmission is necessary for the block corresponding to the retransmission portion when the error rate is equal to or higher than a predetermined threshold and the number of decoding iterations reaches a predetermined number. Notify the transmission / reception unit 111.
- the control channel transmission / reception unit 111 receives a control signal indicating whether or not the retransmission part is included in the packet via the L1 control channel, for example, from the transmission device. Further, the control channel transmission / reception unit 111 transmits ACK / NAK to the transmission apparatus in FIG. 1 according to the necessity of retransmission notified from the output switching unit 207-3 and the output switching unit 207-6.
- step 1 of FIG. 12 it is assumed that two packets 1 and 2 are transmitted from the transmission device to the reception device, but both of the reception devices failed to receive and NAK was returned. To do. Further, consider a case where two retransmission packets 1 and 2 are transmitted, retransmission packet 1 fails to be received and NAK is returned, and retransmission packet 2 is successfully received and ACK is returned.
- step 2 of FIG. 12 first, the retransmission packet 1 is combined with the received packets 1 and 2 held in the retransmission buffer unit 203 by the packet combining unit 207-1, and each combined packet is combined.
- decoding is attempted by the decoding unit 207-2, but the decoding fails.
- the NAK corresponding to the new part in the retransmission packet 1 is returned from the control channel transmission / reception unit 111 to the transmission device via the L1 control channel, for example.
- the retransmission packet 2 is combined with the received packets 1 and 2 held in the retransmission buffer unit 203 by the packet combining unit 207-1 and decoded by the decoding unit 207-2 for each combined packet. Tried.
- the new part (white part) in the retransmission packet 2 is successfully decoded, and the new part is obtained in the output switching unit 207-3.
- the information bits of the new part are output from the output switching unit 207-3 to the subsequent processing unit and also output to the retransmission partial combining unit 207-4.
- an ACK corresponding to the new part in the retransmission packet 2 is returned from the control channel transmission / reception unit 111 to the transmission device via, for example, the L1 control channel.
- step 2 of FIG. 12 first, retransmission packet 1 is combined with received packets 1 and 2 held in retransmission buffer unit 203 in retransmission partial combining section 207-4, and each combined packet is combined.
- decoding is attempted by the decoding unit 207-5. However, both decodings fail.
- the retransmission partial combining unit 207-4 receives the received packets 1 and 2 held in the retransmission buffer unit 203 and the retransmission packet 2 input from the output switching unit 207-3. Are synthesized with each new part.
- Decoding section 207-5 attempts to decode each composite packet. As a result, decoding of the combined packet 1 including the retransmission portion of the retransmission packet 2 succeeds, decoding of the combined packet 2 including the retransmission portion of the retransmission packet 2 fails, and the information bit of the packet 1 is output switched. Part 207-6.
- the information bits of packet 1 restored by retransmission are output from the output switching unit 207-6 to the subsequent processing unit and also output to the packet combining unit 207-1. Further, based on the notification from the output switching unit 207-6, the ACK corresponding to each of the packet 1 and the retransmission packet 2 is returned from the control channel transmission / reception unit 111 to the transmission device via the L1 control channel, for example.
- the packet combining unit 207-1 receives the received packets 1 and 2, In addition, the information bits of the packet 1 input from the output switching unit 207-6 are combined. Then, the decoding unit 207-2 tries the second decoding for each synthesized packet. As a result, the new part (white part) in the retransmission packet 1 is successfully decoded, and the new part is obtained in the output switching unit 207-3. As a result, the information bits of the new part are output from the output switching unit 207-3 to the subsequent processing unit and also output to the retransmission partial combining unit 207-4. Further, based on the notification from the output switching unit 207-3, an ACK corresponding to the new part in the retransmission packet 1 is returned from the control channel transmission / reception unit 111 to the transmission device via, for example, the L1 control channel.
- retransmission packet 1 is input from retransmission packet combining section 207-4, received packet 2 remaining in retransmission buffer section 203, and output switching section 207-3. It is combined with the new part of the retransmission packet 1 respectively.
- Decoding section 207-5 attempts to decode each composite packet. As a result, decoding of the combined packet 2 including the retransmission portion of the retransmission packet 1 is successful, and the information bits of the packet 2 are obtained in the output switching unit 207-6. As a result, the information bits of packet 2 restored by retransmission are output from output switching section 207-6 to the subsequent processing section and also output to packet combining section 207-1. Further, based on the notification from the output switching unit 207-6, the control channel transmission / reception unit 111 returns, for example, ACKs respectively corresponding to the packet 2 and the retransmission packet 1 to the transmission device via the L1 control channel.
- decoding can be successful by repeating the decoding process a plurality of times using other decoding results based on retransmission.
- 1 is installed in a radio base station, for example, and the receiver in FIG. 2 is installed in a radio mobile terminal, for example.
- An example of the control operation for selection has been described with reference to the operation flowcharts of FIGS. This is a case assuming downlink communication from a radio base station to a radio mobile terminal.
- the transmission apparatus of FIG. 1 is installed in, for example, a wireless mobile terminal and the reception apparatus of FIG. This is a case assuming uplink communication from a wireless mobile terminal to a wireless base station.
- the control channel transmission / reception unit 111 in the reception device in FIG. 2 can be the same device as the control channel transmission / reception unit 111 in the transmission device in FIG. 1 in the same radio base station.
- the control operation for selecting the HARQ scheme for the receiving apparatus is the HARQ scheme selection shown in the operation flowchart of FIG. 7 performed by the control channel transmission / reception unit 111 for the transmitting apparatus of FIG. 1 in the radio base station. It is executed as the same operation as the control operation for.
- the control channel transmission / reception unit 111 in the transmission apparatus in FIG. 1 may be the same apparatus as the control channel transmission / reception unit 111 in the reception apparatus in FIG. 2 in the same radio mobile terminal. it can.
- the control operation for selecting the HARQ scheme for the transmitting apparatus is the HARQ scheme selection shown in the operation flowchart of FIG. 11 performed by the control channel transmitting / receiving unit 111 for the receiving apparatus of FIG. 2 in the radio mobile terminal. It is executed as the same operation as the control operation for.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Quality & Reliability (AREA)
- Mobile Radio Communication Systems (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
Abstract
Description
G-HARQ方式では、送信装置は、再送データを、新たに流入してくるパケットが割り当てられるチャネルにおいて、その新規パケットのパリティビット部ではなく情報部(ペイロード)において、新規データと共にグループ化する。このとき、新規データと再送データは、一体となって新たに符号化され、パリティビットも新たに計算されて、新たなパケットとして送信される。受信装置は、そのパケットを復号することにより、新規パケットと再送パケットを分離する。受信装置は、再送されたパケットに対して、CC方式又はIR方式に基づくパケット復元処理を実行する。
Wu Jianming, W. Tong, and J. Li, "Non-complete puncture based re-transmission for HARQ", C50-20011105-025, 3GPP2 TSG-C WG5, November 5, 2001 Wu Jianming "Grouped and Encoded Packet based HARQ for LTE-Advanced", R1-083777, 3GPP TSG-RAN1 #54BIS, Prague, Czech, September 29 - October 3, 2008
第1の態様は、受信装置から返信される送達確認情報に基づいて、その受信装置に復号に失敗したパケットを破棄せずに再送されたパケットと組み合わせて復号させるために、パケットの送信の再送を制御する送信装置を前提とし、以下の構成を有する。
再送バッファ部は、そのブロック生成部によって生成される情報ビットのブロックを再送に備えて一時的に保持する。
再送部分取得部は、再送バッファ部に保持されている再送のためのブロックから送信すべき再送部分を取得する。
送信処理部は、その変調部の出力を送信する。
送信制御部は、受信装置における通信チャネルの通信品質を示す情報に基づいて、符号化方式切替部を制御する。この送信制御部は例えば、受信装置における通信チャネルの通信品質を示す情報として、受信装置から通信チャネルの通信品質を示すチャネル品質指標を定期的に受信し、そのチャネル品質指標に基づいて通信チャネルで実行される通信の変調コード方式を制御し、通信チャネルに対して現在実行中の通信の変調コード方式に対応する通信品質と、現在受信装置から通知されているその通信チャネルに対応するチャネル品質指標が示す通信品質との誤差を算出し、その誤差が所定の閾値よりも大きい場合に符号化方式切替部に第1の符号化部を選択させ、それ以外の場合に符号化方式切替部に第2の符号化部を選択させるように構成することができる。また、送信制御部は例えば、受信装置における通信チャネルの通信品質を示す情報として、受信装置からその受信装置が搭載される移動端末装置の移動速度を示す移動速度情報を定期的に受信し、その移動速度情報が所定の閾値よりも大きい場合に符号化方式切替部に第1の符号化部を選択させ、それ以外の場合に符号化方式切替部に第2の符号化部を選択させるように構成することができる。
復調部は、受信信号を構成する通信チャネルから受信パケットを復調する。
再送バッファ部は、その受信パケットを再送パケットとの合成に備えて一時的に保持する。
受信制御部は、通信チャネルの通信品質を示す情報に基づいて、復号方式切替部を制御する。この受信制御部は例えば、通信チャネルの通信品質を示す情報として、第1の復号部と第2の復号部の何れを選択させるべきかを指示する第1の選択情報を、通信チャネルに対応する制御チャネルを用いて送信装置から受信し、その第1の選択情報に基づいて、復号方式切替部を制御するように構成することができる。
また、上述の第2の態様の構成において、受信制御部は例えば、通信チャネルにおける符号化の効率を表す符号化率として、第3の復号部と第4の復号部の何れを選択させるべきかを指示する第2の選択情報を、通信チャネルに対応する制御チャネルを用いて送信装置から受信し、その第2の選択情報に基づいて、復号方式切替部を制御するように構成することができる。
図1は、パケット送受信システムの送信装置の実施形態の構成図である。また、図2は、同じく受信装置の実施形態の構成図である。パケット送受信システムは例えば、無線移動端末(携帯電話端末等)と無線基地局との間の通信システムとして構成される。この場合に、図1の送信装置は、無線基地局のダウンリンク側と無線移動端末のアップリンク側の双方に装備される。図2の受信装置は、無線基地局のアップリンク側と無線移動端末のダウンリンク側の双方に装備される。パケット受信システムは例えば、3GPPにて標準化作業が進められているLTE通信規格におけるE-UTRA(Evolved Universal Terrestrial Radio Access)システムとして実現することができる。
特性1 データパケットの再送率が高いときには、再送処理遅延の大きいNCP-HARQ方式やG-HARQ方式よりも、フルHARQ方式のほうが有利である。
特性2 データパケットの再送率が低くデータパケットが高符号化率で配送されるときには、G-HARQ方式が有利である。
特性3 データパケットの再送率が低くデータパケットが低符号化率で配送されるときには、NCP-HARQ方式が有利である。
具体的には、図1の送信装置においては、制御チャネル送受信部111がHARQ方式切替部105を制御することにより、また、図2の受信装置においては、図1と共通の制御チャネル送受信部111がHARQ方式切替部204を制御することにより、それぞれHARQ方式の自動切替えを実現する。
MCS1誤差=CR3-CR1
なお、一般に、フィードバック間隔が変化しなければ、MCS誤差間隔は処理遅延に等しい。一般的なケースとして、MCS誤差を示す数式は、下記のように表わされる。
MCSn (Error) =CRn -CRn-k ・・・(1)
ここで、kは、処理遅延のインデックスである。
今、パケット送受信システムとして例えばE-UTRA通信システムが採用される場合には、図4に示されるデータフォーマットが採用される。即ちまず、図4(a)に示されるように、10msec(ミリ秒)長の無線フレームを#0~#20に20分割した0.5msec長のスロットの例えば2つで、1サブフレームが構成される。そして、図4(b)に示されるように、そのサブフレーム内に、L1制御チャネルとデータチャネルが割り当てられる。
L1制御チャネルには、前述したCQIが挿入されるほか、採用されるHARQ方式に対応して送信装置と受信装置の間で通信が必要な各種制御情報が挿入されて伝送される。
次に、NCP-HARQ方式とG-HARQ方式の選択制御のための実装方式としては、3つの案が考えられる。第1の案は、L1制御チャネルの1ビットを使用する方式である。第2の案は、前述したような高レイヤ制御情報から1ビットを使用する方式である。そして、第3の案は、送信装置と受信装置のそれぞれにおいて、MCSレベル等に基づいて算出される符号化率を所定閾値(=閾値2)と比較する、送信装置と受信装置とでトランスペアレントな判定を行う方式である。
・フルHARQ又は部分的HARQを選択指示するために、高レイヤ制御情報から1ビットを用いる。
・追加ビット無しにNCP-HARQ又はG-HARQを選択指示するために、送信装置と受信装置のそれぞれにおいて、MCSレベル等に基づいて算出される符号化率を所定閾値(=閾値2)と比較する判定を行う。
以上のHARQ方式の選択方式に基づく図1及び図2の実施形態の具体的な動作について、以下に説明する。
制御チャネル送受信部111は、上記判定において、算出したMCS誤差が閾値1より大きいと判定した場合には、HARQ方式切替部105を制御して、フルHARQ符号化部106を動作させるように制御する(図7のステップS703)。
再送パケット符号化部106-2は、再送ブロックが入力された場合には、それを情報ビット部に含み、それに対応するパリティビットをパリティビット部に含む再送パケットを生成する。
パンクチャ部107-2は、上記新規パケットが割り当てられるチャネルにおいて、その新規パケットのパリティビット部が割り当てられるべきフレーム構成ビット部分の一部に、再送部分取得部104から出力された再送ブロックの情報ビットを順次パンクチャする。この結果、新規パケットにおけるパリティビット部の割当ては、フレーム構成ビットの一部がパンクチャされた分だけ遅延させられる。上記パンクチャ処理は、再送部分取得部104から出力された再送ブロックの全ての情報ビットの割当てが完了するまで、フレーム構成ビットの一部がパターンを変えながら選択されそこにパンクチャされてゆく。パンクチャ部107-2は、結果として得られる1つの通信チャネルのフレームに割り当てられた合成パケット(図9の「再送信」パケットを参照)を、変調部109へ出力する。
次に、図2の受信装置が例えば無線移動端末のダウンリンク系に設置される場合において、制御チャネル送受信部111が実行するHARQ方式の選択のための制御動作の一例について、図11に示される動作フローチャートに基づいて説明する。
再送バッファ部203は、受信パケットを将来受信される再送パケットとの合成に備えて一時的に保持する。そして、再送バッファ部203は、受信パケットが再送部分合成部205-3、207-4やパケット合成部207-1へ入力されると、受信パケットに含まれる再送部分に対応する過去の受信パケットをそれらへ出力する。
制御チャネル送受信部111は、受信したフルHARQ方式選択ビットの値が1である場合には、HARQ方式切替部204を制御して、フルHARQ復号部205を動作させるように制御する(図11のステップS1103)。
パケット合成部207-1は、受信パケットに再送部分が含まれていないと判定したときには、受信パケットをそのまま復号部207-2へ出力する。
復号部207-2は、パケット合成部207-1から出力される受信パケット又は合成パケットを復号する。
再送部分合成部207-4は、受信パケットに再送部分が含まれていると判定したときには、出力切替部207-3から出力される新規部分の復号結果を利用して受信パケットから再送部分を抽出する。そして、再送部分合成部207-4は、抽出した再送部分に対応する過去の受信パケットを再送バッファ部203から取得し、抽出した再送部分と過去の受信パケットとを合成する。これにより、再送部分合成部207-4は、過去の受信パケットに対して、新たな受信パケットの再送部分を合成した合成パケットを生成することになる。
以上、図1の送信装置が例えば無線基地局に設置される場合、及び図2の受信装置が例えば無線移動端末に設置される場合の各々にて、制御チャネル送受信部111が実行するHARQ方式の選択のための制御動作の一例を、図7及び図11の動作フローチャートで説明した。これは、無線基地局から無線移動端末に向かうダウンリンク系の通信を想定したケースである。
Claims (15)
- 受信装置から返信される送達確認情報に基づいて、該受信装置に復号に失敗したパケットを破棄せずに再送されたパケットと組み合わせて復号させるために、前記パケットの送信の再送を制御する送信装置であって、
送信されるべき情報ビットから所定サイズのブロックを生成するブロック生成部と、
該ブロック生成部によって生成される情報ビットのブロックを再送に備えて一時的に保持する再送バッファ部と、
前記ブロック生成部が生成するブロックから送信すべき新規部分を取得する新規部分取得部と、
前記再送バッファ部に保持されている再送のためのブロックから送信すべき再送部分を取得する再送部分取得部と、
前記新規部分取得部から取得される新規部分から新規パケットを生成し、前記再送部分取得部から取得される再送部分から再送パケットを生成し、該新規パケット及び再送パケットをそれぞれ個別の通信チャネルに割り当て、その結果得られる個別の通信チャネルデータを出力する第1の符号化部と、
前記新規部分取得部から取得される新規部分と前記再送部分取得部から出力された再送部分とを混合して得られるパケットを通信チャネルに割当て、その結果得られる通信チャネルデータを出力する第2の符号化部と、
前記第1の符号化部又は前記第2の符号化部から出力される通信チャネルデータを変調する変調部と、
該変調部の出力を送信する送信処理部と
前記第1の符号化部又は前記第2の符号化部の動作を切り替える符号化方式切替部と、
前記受信装置における前記通信チャネルの通信品質を示す情報に基づいて、前記符号化方式切替部を制御する送信制御部と、
を含むことを特徴とする送信装置。 - 前記送信制御部は、
前記受信装置における前記通信チャネルの通信品質を示す情報として、前記受信装置から前記通信チャネルの通信品質を示すチャネル品質指標を定期的に受信し、
該チャネル品質指標に基づいて前記通信チャネルで実行される通信の変調コード方式を制御し、
前記通信チャネルに対して現在実行中の通信の変調コード方式に対応する通信品質と、現在前記受信装置から通知されている該通信チャネルに対応するチャネル品質指標が示す通信品質との誤差を算出し、該誤差が所定の閾値よりも大きい場合に前記符号化方式切替部に前記第1の符号化部を選択させ、それ以外の場合に前記符号化方式切替部に前記第2の符号化部を選択させる、
ことを特徴とする請求項1に記載の送信装置。 - 前記送信制御部は、
前記受信装置における前記通信チャネルの通信品質を示す情報として、前記受信装置から該受信装置が搭載される移動端末装置の移動速度を示す移動速度情報を定期的に受信し、
該移動速度情報が所定の閾値よりも大きい場合に前記符号化方式切替部に前記第1の符号化部を選択させ、それ以外の場合に前記符号化方式切替部に前記第2の符号化部を選択させる、
ことを特徴とする請求項1に記載の送信装置。 - 前記第2の符号化部は、
前記新規部分取得部から取得される新規部分から新規パケットを生成し、該新規パケットを通信チャネルに割り当てると共に、該通信チャネルにおいて、該新規パケットのパリティビット部が割り当てられるべきビット位置の一部に、前記再送部分取得部から出力された再送部分の情報ビットを、前記新規パケットの前記ビット位置の一部への割当てを遅らせて挿入し、その結果得られる通信チャネルデータを出力する第3の符号化部と、
前記新規部分取得部から取得される新規部分と前記再送部分取得部から出力された再送部分とを該新規部分の割当てを削減するように混合し情報ビット部を構成してパケットを生成し、該パケットを通信チャネルに割り当て、その結果得られる通信チャネルデータを出力する第4の符号化部とから構成され、
前記符号化方式切替部は、前記第1の符号化部、前記第3の符号化部、又は前記第4の符号化部の動作を切り替え、
前記送信制御部は、前記通信チャネルにおける符号化の効率を表す符号化率を算出し、前記第2の符号化部を選択したときに更に、該符号化率が所定の閾値よりも大きい場合に前記符号化方式切替部に前記第4の符号化部を選択させ、それ以外の場合に前記符号化方式切替部に前記第3の符号化部を選択させる、
ことを特徴とする請求項1乃至3の何れか1項に記載の送信装置。 - 前記送信制御部は、前記符号化方式切替部に前記第1の符号化部と前記第2の符号化部の何れを選択させたかを示す第1の選択情報を、前記通信チャネルに対応する制御チャネルを用いて前記受信装置に通知する、
ことを特徴とする請求項1乃至4の何れか1項に記載の送信装置。 - 前記送信制御部は、前記符号化方式切替部に前記第3の符号化部と前記第4の符号化部の何れを選択させたかを示す第2の選択情報を、前記通信チャネルに対応する制御チャネルを用いて前記受信装置に通知する、
ことを特徴とする請求項1乃至5の何れか1項に記載の送信装置。 - 送信装置に受信パケットの成否を示す送達確認情報を返信しながら、復号に失敗した前記受信パケットを破棄せずに前記送信装置から再送された受信パケットと組み合わせて復号しながら、前記受信パケットの再送を制御する受信装置であって、
受信信号を受信する受信処理部と
前記受信信号を構成する通信チャネルから前記受信パケットを復調する復調部と、
該受信パケットを再送パケットとの合成に備えて一時的に保持する再送バッファ部と、
前記受信パケットの通信チャネルを識別することにより、該受信パケットを新規部分が格納されている新規パケットと再送部分が格納されている再送パケットに振り分け、前記新規パケットからは新規部分の情報ビットを抽出して出力し、前記再送パケットからは再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第1の復号部と、
前記受信パケットから新規部分と再送部分をそれぞれ抽出し、前記新規部分の情報ビットを抽出して出力し、前記再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第2の復号部と、
前記第1の復号部又は前記第2の復号部の動作を切り替える復号方式切替部と、
前記通信チャネルの通信品質を示す情報に基づいて、前記復号方式切替部を制御する受信制御部と、
を含むことを特徴とする受信装置。 - 前記受信制御部は、
前記通信チャネルの通信品質を示す情報として、前記第1の復号部と前記第2の復号部の何れを選択させるべきかを指示する第1の選択情報を、前記通信チャネルに対応する制御チャネルを用いて前記送信装置から受信し、
該第1の選択情報に基づいて、前記復号方式切替部を制御する、
ことを特徴とする請求項7に記載の受信装置。 - 前記第2の復号部は、
前記受信パケットから新規部分が格納されている新規パケットと再送部分が格納されている再送パケットを分離し、前記新規パケットからは新規部分の情報ビットを抽出して出力し、前記再送パケットからは再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第3の復号部と、
前記再送バッファ部に保持されている受信に失敗した受信パケット又は先行して抽出された新規部分又は再送部分と合成しながら、前記受信パケットの情報ビットから新規部分と再送部分を分離し、該新規部分の情報ビットを抽出して出力し、該再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケット又は先行して抽出された新規部分又は再送部分と合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第4の復号部とから構成され、
前記復号方式切替部は、前記第1の復号部、前記第3の復号部、又は前記第4の復号部の動作を切り替え、
前記受信制御部は、前記通信チャネルにおける符号化の効率を表す符号化率を取得し、前記第2の復号部を選択したときに更に、該符号化率が所定の閾値よりも大きい場合に前記復号方式切替部に前記第4の復号部を選択させ、それ以外の場合に前記復号方式切替部に前記第3の復号部を選択させる、
ことを特徴とする請求項7又は8の何れか1項に記載の受信装置。 - 前記受信制御部は、前記通信チャネルにおける符号化の効率を表す符号化率を、前記通信チャネルに対して現在実行中の通信の変調コード方式から算出して取得する、
ことを特徴とする請求項7乃至9の何れか1項に記載の受信装置。 - 前記受信制御部は、
前記通信チャネルにおける符号化の効率を表す符号化率として、前記第3の復号部と前記第4の復号部の何れを選択させるべきかを指示する第2の選択情報を、前記通信チャネルに対応する制御チャネルを用いて前記送信装置から受信し、
該第2の選択情報に基づいて、前記復号方式切替部を制御する、
ことを特徴とする請求項7乃至9の何れか1項に記載の受信装置。 - 送達確認情報を通信しながら、復号に失敗した受信パケットを破棄せずに再送された受信パケットと組み合わせて復号しながら、前記受信パケットの再送を制御する通信システムであって、
送信されるべき情報ビットから所定サイズのブロックを生成するブロック生成部と、
該ブロック生成部によって生成される情報ビットのブロックを再送に備えて一時的に保持する再送バッファ部と、
前記ブロック生成部が生成するブロックから送信すべき新規部分を取得する新規部分取得部と、
前記再送バッファ部に保持されている再送のためのブロックから送信すべき再送部分を取得する再送部分取得部と、
前記新規部分取得部から取得される新規部分から新規パケットを生成し、前記再送部分取得部から取得される再送部分から再送パケットを生成し、該新規パケット及び再送パケットをそれぞれ個別の通信チャネルに割り当て、その結果得られる個別の通信チャネルデータを出力する第1の符号化部と、
前記新規部分取得部から取得される新規部分と前記再送部分取得部から出力された再送部分とを混合して得られるパケットを通信チャネルに割当て、その結果得られる通信チャネルデータを出力する第2の符号化部と、
前記第1の符号化部又は前記第2の符号化部から出力される通信チャネルデータを変調する変調部と、
該変調部の出力を送信する送信処理部と
前記第1の符号化部又は前記第2の符号化部の動作を切り替える符号化方式切替部と、
受信装置における前記通信チャネルの通信品質を示す情報に基づいて、前記符号化方式切替部を制御する送信制御部と、
を含む送信装置と、
受信信号を受信する受信処理部と
前記受信信号を構成する通信チャネルから前記受信パケットを復調する復調部と、
該受信パケットを再送パケットとの合成に備えて一時的に保持する再送バッファ部と、
前記受信パケットの通信チャネルを識別することにより、該受信パケットを新規部分が格納されている新規パケットと再送部分が格納されている再送パケットに振り分け、前記新規パケットからは新規部分の情報ビットを抽出して出力し、前記再送パケットからは再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第1の復号部と、
前記受信パケットから新規部分と再送部分をそれぞれ抽出し、前記新規部分の情報ビットを抽出して出力し、前記再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第2の復号部と、
前記第1の復号部又は前記第2の復号部の動作を切り替える復号方式切替部と、
前記通信チャネルの通信品質を示す情報に基づいて、前記復号方式切替部を制御する受信制御部と、
を含む受信装置とからなることを特徴とする通信システム。 - 前記第2の符号化部は、
前記新規部分取得部から取得される新規部分から新規パケットを生成し、該新規パケットを通信チャネルに割り当てると共に、該通信チャネルにおいて、該新規パケットのパリティビット部が割り当てられるべきビット位置の一部に、前記再送部分取得部から出力された再送部分の情報ビットを、前記新規パケットの前記ビット位置の一部への割当てを遅らせて挿入し、その結果得られる通信チャネルデータを出力する第3の符号化部と、
前記新規部分取得部から取得される新規部分と前記再送部分取得部から出力された再送部分とを該新規部分の割当てを削減するように混合し情報ビット部を構成してパケットを生成し、該パケットを通信チャネルに割り当て、その結果得られる通信チャネルデータを出力する第4の符号化部とから構成され、
前記符号化方式切替部は、前記第1の符号化部、前記第3の符号化部、又は前記第4の符号化部の動作を切り替え、
前記送信制御部は、前記通信チャネルにおける符号化の効率を表す符号化率を算出し、前記第2の符号化部を選択したときに更に、該符号化率が所定の閾値よりも大きい場合に前記符号化方式切替部に前記第4の符号化部を選択させ、それ以外の場合に前記符号化方式切替部に前記第3の符号化部を選択させ、
前記第2の復号部は、
前記受信パケットから新規部分が格納されている新規パケットと再送部分が格納されている再送パケットを分離し、前記新規パケットからは新規部分の情報ビットを抽出して出力し、前記再送パケットからは再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第3の復号部と、
前記再送バッファ部に保持されている受信に失敗した受信パケット又は先行して抽出された新規部分又は再送部分と合成しながら、前記受信パケットの情報ビットから新規部分と再送部分を分離し、該新規部分の情報ビットを抽出して出力し、該再送部分の情報ビットを取り出して前記再送バッファ部に保持されている受信に失敗した受信パケット又は先行して抽出された新規部分又は再送部分と合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第4の復号部とから構成され、
前記復号方式切替部は、前記第1の復号部、前記第3の復号部、又は前記第4の復号部の動作を切り替え、
前記受信制御部は、前記通信チャネルにおける符号化の効率を表す符号化率を取得し、前記第2の復号部を選択したときに更に、該符号化率が所定の閾値よりも大きい場合に前記復号方式切替部に前記第4の復号部を選択させ、それ以外の場合に前記復号方式切替部に前記第3の復号部を選択させる、
ことを特徴とする請求項12に記載の通信システム。 - 送達確認情報を通信しながら、復号に失敗した受信パケットを破棄せずに再送された受信パケットと組み合わせて復号しながら、前記受信パケットの再送を制御する通信方法であって、
送信されるべき情報ビットから所定サイズのブロックを生成するブロック生成ステップと、
該ブロック生成ステップによって生成される情報ビットのブロックを再送に備えて一時的に保持する再送バッファリングステップと、
前記ブロック生成ステップが生成するブロックから送信すべき新規部分を取得する新規部分取得ステップと、
前記再送バッファリングステップにて保持されている再送のためのブロックから送信すべき再送部分を取得する再送部分取得ステップと、
前記新規部分取得ステップから取得される新規部分から新規パケットを生成し、前記再送部分取得ステップから取得される再送部分から再送パケットを生成し、該新規パケット及び再送パケットをそれぞれ個別の通信チャネルに割り当て、その結果得られる個別の通信チャネルデータを出力する第1の符号化ステップと、
前記新規部分取得ステップから取得される新規部分と前記再送部分取得ステップから出力された再送部分とを混合して得られるパケットを通信チャネルに割当て、その結果得られる通信チャネルデータを出力する第2の符号化ステップと、
前記第1の符号化ステップ又は前記第2の符号化ステップから出力される通信チャネルデータを変調する変調ステップと、
該変調ステップの出力を送信する送信処理ステップと
前記第1の符号化ステップ又は前記第2の符号化ステップの動作を切り替える符号化方式切替ステップと、
受信装置における前記通信チャネルの通信品質を示す情報に基づいて、前記符号化方式切替ステップを制御する送信制御ステップと、
を含む送信装置と、
受信信号を受信する受信処理ステップと
前記受信信号を構成する通信チャネルから前記受信パケットを復調する復調ステップと、
該受信パケットを再送パケットとの合成に備えて一時的に保持する再送バッファリングステップと、
前記受信パケットの通信チャネルを識別することにより、該受信パケットを新規部分が格納されている新規パケットと再送部分が格納されている再送パケットに振り分け、前記新規パケットからは新規部分の情報ビットを抽出して出力し、前記再送パケットからは再送部分の情報ビットを取り出して前記再送バッファリングステップにて保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第1の復号ステップと、
前記受信パケットから新規部分と再送部分をそれぞれ抽出し、前記新規部分の情報ビットを抽出して出力し、前記再送部分の情報ビットを取り出して前記再送バッファリングステップにて保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第2の復号ステップと、
前記第1の復号ステップ又は前記第2の復号ステップの動作を切り替える復号方式切替ステップと、
前記通信チャネルの通信品質を示す情報に基づいて、前記復号方式切替ステップを制御する受信制御ステップと、
を含む受信装置とからなることを特徴とする通信方法。 - 前記第2の符号化ステップは、
前記新規部分取得ステップから取得される新規部分から新規パケットを生成し、該新規パケットを通信チャネルに割り当てると共に、該通信チャネルにおいて、該新規パケットのパリティビット部が割り当てられるべきビット位置の一部に、前記再送部分取得ステップから出力された再送部分の情報ビットを、前記新規パケットの前記ビット位置の一部への割当てを遅らせて挿入し、その結果得られる通信チャネルデータを出力する第3の符号化ステップと、
前記新規部分取得ステップから取得される新規部分と前記再送部分取得ステップから出力された再送部分とを該新規部分の割当てを削減するように混合し情報ビット部を構成してパケットを生成し、該パケットを通信チャネルに割り当て、その結果得られる通信チャネルデータを出力する第4の符号化ステップとから構成され、
前記符号化方式切替ステップは、前記第1の符号化ステップ、前記第3の符号化ステップ、又は前記第4の符号化ステップの動作を切り替え、
前記送信制御ステップは、前記通信チャネルにおける符号化の効率を表す符号化率を算出し、前記第2の符号化ステップを選択したときに更に、該符号化率が所定の閾値よりも大きい場合に前記符号化方式切替ステップに前記第4の符号化ステップを選択させ、それ以外の場合に前記符号化方式切替ステップに前記第3の符号化ステップを選択させ、
前記第2の復号ステップは、
前記受信パケットから新規部分が格納されている新規パケットと再送部分が格納されている再送パケットを分離し、前記新規パケットからは新規部分の情報ビットを抽出して出力し、前記再送パケットからは再送部分の情報ビットを取り出して前記再送バッファリングステップにて保持されている受信に失敗した受信パケットと合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第3の復号ステップと、
前記再送バッファリングステップにて保持されている受信に失敗した受信パケット又は先行して抽出された新規部分又は再送部分と合成しながら、前記受信パケットの情報ビットから新規部分と再送部分を分離し、該新規部分の情報ビットを抽出して出力し、該再送部分の情報ビットを取り出して前記再送バッファリングステップにて保持されている受信に失敗した受信パケット又は先行して抽出された新規部分又は再送部分と合成することにより該受信パケットを復元して該受信パケットから情報ビットを抽出して出力する第4の復号ステップとから構成され、
前記復号方式切替ステップは、前記第1の復号ステップ、前記第3の復号ステップ、又は前記第4の復号ステップの動作を切り替え、
前記受信制御ステップは、前記通信チャネルにおける符号化の効率を表す符号化率を取得し、前記第2の復号ステップを選択したときに更に、該符号化率が所定の閾値よりも大きい場合に前記復号方式切替ステップに前記第4の復号ステップを選択させ、それ以外の場合に前記復号方式切替ステップに前記第3の復号ステップを選択させる、
ことを特徴とする請求項14に記載の通信方法。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2010534610A JP5141771B2 (ja) | 2008-10-24 | 2008-10-24 | 適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 |
PCT/JP2008/003032 WO2010046956A1 (ja) | 2008-10-24 | 2008-10-24 | 適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 |
CN200880131582XA CN102187610A (zh) | 2008-10-24 | 2008-10-24 | 基于自适应混合自动重传请求方式的发送装置、接收装置、通信系统以及通信方法 |
US13/088,812 US8457059B2 (en) | 2008-10-24 | 2011-04-18 | Transmission apparatus, reception apparatus, communication system and communication method using adaptive hybrid automatic retransmission request method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2008/003032 WO2010046956A1 (ja) | 2008-10-24 | 2008-10-24 | 適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/088,812 Continuation US8457059B2 (en) | 2008-10-24 | 2011-04-18 | Transmission apparatus, reception apparatus, communication system and communication method using adaptive hybrid automatic retransmission request method |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010046956A1 true WO2010046956A1 (ja) | 2010-04-29 |
Family
ID=42119015
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2008/003032 WO2010046956A1 (ja) | 2008-10-24 | 2008-10-24 | 適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 |
Country Status (4)
Country | Link |
---|---|
US (1) | US8457059B2 (ja) |
JP (1) | JP5141771B2 (ja) |
CN (1) | CN102187610A (ja) |
WO (1) | WO2010046956A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2011082869A (ja) * | 2009-10-08 | 2011-04-21 | Ntt Docomo Inc | 無線通信システム、無線送信装置及び無線受信装置 |
JPWO2023105720A1 (ja) * | 2021-12-09 | 2023-06-15 |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102012200181B4 (de) * | 2012-01-09 | 2024-06-20 | Robert Bosch Gmbh | Steuereinrichtungen an Bord des Kraftfahrzeugs |
US10098095B2 (en) * | 2012-05-25 | 2018-10-09 | Qualcomm Incorporated | Feedback to enhance rate prediction with bursty interference |
CN103825685B (zh) * | 2012-11-16 | 2018-05-11 | 华为技术有限公司 | 用于实现混合自动重传请求的方法和装置 |
CN105940628A (zh) * | 2013-10-30 | 2016-09-14 | 华为技术有限公司 | 混合自动重传请求数据解码方法、节点设备及解码系统 |
RU2669743C1 (ru) * | 2014-03-31 | 2018-10-15 | Хуавэй Текнолоджиз Ко., Лтд. | Способ и устройство гибридного автоматического запроса на повторение с полярным кодом и беспроводное устройство связи |
CN105634656A (zh) * | 2014-10-29 | 2016-06-01 | 中国移动通信集团公司 | 一种确定终端调制编码方式 mcs 的方法、终端和基站 |
WO2016120829A1 (en) * | 2015-01-29 | 2016-08-04 | Telefonaktiebolaget Lm Ericsson (Publ) | System and method for handling uplink transmissions |
CN105991235B (zh) * | 2015-03-04 | 2020-10-30 | 株式会社Ntt都科摩 | 一种调整编码调制方案的方法、用户设备及基站 |
CN108141313B (zh) * | 2015-09-30 | 2020-12-18 | 日本电气株式会社 | 通信装置、通信系统和控制方法 |
JP6821014B2 (ja) * | 2016-08-26 | 2021-01-27 | 華為技術有限公司Huawei Technologies Co.,Ltd. | 符号化レート調節方法および端末 |
US20180083750A1 (en) * | 2016-09-22 | 2018-03-22 | Mediatek Inc. | Design For Communication Systems Suffering Burst Error |
CN108282257A (zh) * | 2017-01-06 | 2018-07-13 | 株式会社Ntt都科摩 | 用户终端、在其处的反馈方法、基站和在其处的方法 |
US11121821B2 (en) | 2017-02-06 | 2021-09-14 | Telefonaktiebolaget Lm Ericsson (Publ) | Enhancements for retransmission due to conflicting transmissions for different services |
KR102251634B1 (ko) * | 2017-06-15 | 2021-05-13 | 후지쯔 가부시끼가이샤 | 기지국 장치, 단말기 장치, 무선 통신 시스템, 및 통신 방법 |
CN109151846B (zh) * | 2017-06-16 | 2020-09-11 | 华为技术有限公司 | 一种cp类型的确定方法及终端设备、基站 |
JP7591494B2 (ja) * | 2019-04-23 | 2024-11-28 | パナソニック インテレクチュアル プロパティ コーポレーション オブ アメリカ | 基地局及び通信方法 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7152196B2 (en) * | 2001-12-10 | 2006-12-19 | Nortel Networks Limited | Adaptive multi-mode HARQ system and method |
ATE349828T1 (de) * | 2002-08-13 | 2007-01-15 | Matsushita Electric Ind Co Ltd | Hybrides automatisches wiederholungsaufforderungsprotokoll |
JP4077333B2 (ja) | 2002-12-24 | 2008-04-16 | 松下電器産業株式会社 | 無線送信装置及び無線送信方法 |
KR101009145B1 (ko) * | 2004-01-09 | 2011-01-18 | 엘지전자 주식회사 | 소프트핸드오버중인 단말에서 하향링크ack/nack피드백 판정방법 |
JP4596958B2 (ja) | 2005-04-01 | 2010-12-15 | 株式会社エヌ・ティ・ティ・ドコモ | 無線通信装置及び無線通信方法 |
EP1880501A1 (en) * | 2005-05-13 | 2008-01-23 | Matsushita Electric Industrial Co., Ltd. | Bit reliability equalization by modulation switching for harq |
JP2007116427A (ja) | 2005-10-20 | 2007-05-10 | Sharp Corp | スケジューリング方法、基地局、及び送信機 |
CN101911755A (zh) * | 2008-01-07 | 2010-12-08 | 松下电器产业株式会社 | 无线发送装置和重发控制方法 |
EP2299621A4 (en) * | 2008-07-03 | 2013-12-18 | Fujitsu Ltd | ENCODER, DECODER, ENCODING METHOD, AND DECODING METHOD |
-
2008
- 2008-10-24 JP JP2010534610A patent/JP5141771B2/ja not_active Expired - Fee Related
- 2008-10-24 WO PCT/JP2008/003032 patent/WO2010046956A1/ja active Application Filing
- 2008-10-24 CN CN200880131582XA patent/CN102187610A/zh active Pending
-
2011
- 2011-04-18 US US13/088,812 patent/US8457059B2/en not_active Expired - Fee Related
Non-Patent Citations (2)
Title |
---|
FUJITSU, 3GPP R1-083777, 29 September 2008 (2008-09-29), pages 1 - 11 * |
JUNG-FU CHENG ET AL: "Coding performance of hybrid ARQ schemes", IEEE TRANSACTIONS ON COMMUNICATIONS, vol. 54, no. 6, June 2006 (2006-06-01), pages 1017 - 1029 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2011082869A (ja) * | 2009-10-08 | 2011-04-21 | Ntt Docomo Inc | 無線通信システム、無線送信装置及び無線受信装置 |
EP2309669A3 (en) * | 2009-10-08 | 2011-12-14 | NTT DoCoMo, Inc. | Radio communication system using a hybrid ARQ scheme |
US8743780B2 (en) | 2009-10-08 | 2014-06-03 | Ntt Docomo, Inc. | Radio communication system, radio transmitting apparatus and radio receiving apparatus |
JPWO2023105720A1 (ja) * | 2021-12-09 | 2023-06-15 | ||
JP7483158B2 (ja) | 2021-12-09 | 2024-05-14 | 三菱電機株式会社 | 列車情報管理支援装置、中央装置、表示装置、列車情報管理システム、列車情報管理支援方法および列車情報管理支援プログラム |
Also Published As
Publication number | Publication date |
---|---|
JPWO2010046956A1 (ja) | 2012-03-15 |
JP5141771B2 (ja) | 2013-02-13 |
CN102187610A (zh) | 2011-09-14 |
US8457059B2 (en) | 2013-06-04 |
US20110194518A1 (en) | 2011-08-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5141771B2 (ja) | 適応ハイブリッド自動再送要求方式による送信装置、受信装置、通信システム、及び通信方法 | |
US12166592B2 (en) | HARQ in spatial multiplexing MIMO system | |
CN101075859B (zh) | 用于分组传输的混合自动重发请求方法和装置及传输系统 | |
CN101662346B (zh) | 自动重传控制方法、通信系统及其发射机和接收机 | |
EP3890426B1 (en) | Adaptive transmission method, device and system for satellite communication | |
US8631296B2 (en) | Automatic retransmission controller and retransmission block recombination apparatus | |
JP5360198B2 (ja) | 通信方法、通信システム、通信端末装置、及び通信基地局装置 | |
KR101008636B1 (ko) | 소프터 핸드오버시에 적용되는 패킷 전송 성공 여부 전송방법 | |
CN108631960B (zh) | 一种数据传输方法和相关设备 | |
EP1850520B1 (en) | Mimo transmitting apparatus, and data retransmitting method in mimo system | |
CN101529779B (zh) | 无线通信系统中的传输控制方法及发送装置和接收装置 | |
JP5298648B2 (ja) | 送信機及び受信機並びに送信方法及び受信方法 | |
US7065068B2 (en) | Multi channel stop and wait ARQ communication method and apparatus | |
WO2006093093A1 (ja) | 再送制御方法および無線通信装置 | |
CN101888289A (zh) | 一种混合自动重传方法及装置 | |
JP4077333B2 (ja) | 無線送信装置及び無線送信方法 | |
JP2007312156A (ja) | 誤り訂正符号データの再送制御方法、無線装置及びプログラム | |
EP2507931B1 (en) | Data carrier identification method and system | |
EP2075972A1 (en) | Transmitter | |
JP2005192175A (ja) | 送信装置及び受信装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200880131582.X Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 08877522 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010534610 Country of ref document: JP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 08877522 Country of ref document: EP Kind code of ref document: A1 |