WO2010029764A1 - 無線通信装置及び誤り検出結果フィードバック方法 - Google Patents
無線通信装置及び誤り検出結果フィードバック方法 Download PDFInfo
- Publication number
- WO2010029764A1 WO2010029764A1 PCT/JP2009/004528 JP2009004528W WO2010029764A1 WO 2010029764 A1 WO2010029764 A1 WO 2010029764A1 JP 2009004528 W JP2009004528 W JP 2009004528W WO 2010029764 A1 WO2010029764 A1 WO 2010029764A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- tti
- error detection
- retransmission
- unit
- base station
- Prior art date
Links
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
- H04L1/1607—Details of the supervisory signal
- H04L1/1671—Details of the supervisory signal the supervisory signal being transmitted together with control information
-
- 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
- H04L1/1812—Hybrid protocols; Hybrid automatic repeat request [HARQ]
-
- 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
- H04L2001/0092—Error control systems characterised by the topology of the transmission link
- H04L2001/0097—Relays
Definitions
- the present invention relates to a wireless communication apparatus and an error detection result feedback method.
- 3rd generation mobile communication services have been started, and multimedia communication such as data communication or video communication has become very popular.
- multimedia communication such as data communication or video communication has become very popular.
- the demand for communication in all environments will increase, and the expansion of the communicable area is expected.
- 3GPP-LTE Long Term Evolution
- a UE existing in the vicinity of a cell edge bundles a plurality of TTIs in uplink transmission, and this is used as one HARQ process.
- the uplink reception quality of the base station is improved by encoding small data such as VoIP data at a low coding rate, mapping the obtained codewords to a plurality of bundled TTIs, and transmitting them.
- the plurality of bundled TTIs may be hereinafter referred to as “TTI bundles”.
- FIG. 1 is a diagram for explaining a retransmission process in a communication system to which the TTI-bundling technique is applied.
- FIG. 1 shows a case where three TTIs are bundled.
- the terminal bundles TTIs 0 to 2 and transmits data to the base station.
- the terminal transmits a codeword mapped to at least TTI0 with CRC added thereto. This data is received and decoded by the base station.
- the base station performs error detection using CRC only for data transmitted in the first TTI. If an error is detected, the base station transmits a NACK to the terminal. When receiving the NACK, the terminal retransmits the data in the scheduled retransmission period.
- the scheduled retransmission intervals corresponding to TTIs 0 to 2 are TTIs 8 to 10. Therefore, the terminal retransmits at TTI 8-10.
- the interval (here, 8 TTI) between the scheduled transmission intervals (including the initial transmission interval and the scheduled retransmission interval) is the round trip time (HARQ process) of the HARQ process between the terminal and the base station existing near the cell edge.
- HARQ-RTT is determined by the time taken for the transmission signal (initial transmission signal and NACK) to propagate between the terminal and the base station and the time taken for the transmission signal generation processing of the terminal and the base station.
- the above-described conventional communication system has a problem that unnecessary retransmission is performed. That is, as shown in FIG. 2, the base station performs error detection only on the data transmitted in the first TTI among the bundled TTI groups, and transmits ACK / NACK to the terminal based on the detection result. Therefore, even if the error correction state (ie, the state in which ACK is to be transmitted) is reached while decoding is proceeding to the subsequent TTI in the bundled TTI group, the base station has already transmitted NACK to the terminal. In the case of transmission, the terminal performs a retransmission process. As a result, there is a problem that the system throughput decreases.
- the error correction state ie, the state in which ACK is to be transmitted
- An object of the present invention is to provide a wireless communication apparatus and an error detection result feedback method that improve system throughput by preventing unnecessary retransmission without degrading the quality of retransmission data.
- the radio communication apparatus of the present invention is a base station that receives a radio signal in which a codeword obtained by encoding one transmission data is mapped to a TTI bundle including a plurality of TTIs, and the codeword mapped to the TTI bundle In addition to the error detection result information relating to the codeword transmitted at the end TTI in the TTI bundle, at least one other TTI And a transmission unit that sequentially transmits the error detection result information related to the codeword transmitted in accordance with the detection timing.
- the error detection result feedback method includes a step of receiving a radio signal in which a codeword obtained by encoding one transmission data is mapped to a TTI bundle including a plurality of TTIs, and a codeword mapped to the TTI bundle.
- the step of detecting an error of each decoding result, and the error detection result information related to the code word transmitted at the end TTI in the TTI bundle it is transmitted at least one other TTI And sequentially transmitting error detection result information relating to the codeword in accordance with the detection timing.
- the present invention it is possible to provide a wireless communication apparatus and an error detection result feedback method that improve system throughput by preventing unnecessary retransmission without degrading the quality of retransmission data.
- FIG. 10 is a diagram for explaining a retransmission process in a communication system to which the TTI-bundling technique is applied.
- FIG. 10 is a diagram for explaining a retransmission process in a communication system to which the TTI-bundling technique is applied. Diagram for explaining related technology The block diagram which shows the structure of the terminal which concerns on Embodiment 1 of this invention. The block diagram which shows the structure of the base station which concerns on Embodiment 1 of this invention.
- FIG. 4 is a block diagram showing a configuration of terminal 100 according to Embodiment 1 of the present invention.
- a terminal 100 includes a CRC unit 101, an encoding unit 102, a modulation unit 103, a multiplexing unit 104, a transmission RF unit 105, an antenna 106, a reception RF unit 107, a demodulation unit 108, A decoding unit 109 and a control unit 110 are included.
- the CRC unit 101 performs error detection (CRC: Cyclic Redundancy Check) encoding on the information bit sequence, and outputs the information bit sequence to which the CRC parity bit is added to the encoding unit 102.
- CRC Cyclic Redundancy Check
- the encoding unit 102 includes a circular buffer (not shown).
- the encoding unit 102 turbo-encodes the information bit string to which the CRC parity bits are added at the mother encoding rate, and holds the obtained code word in the circular buffer.
- the encoding unit 102 extracts an output codeword corresponding to the control information received from the control unit 110 from the codeword held in the circular buffer and outputs the codeword to the modulation unit 103.
- the control information received from the control unit 110 includes transmission type information (including a coding rate) indicating transmission by TTI-bundling, a new transmission command, a retransmission preparation command, a retransmission execution command, modulation multilevel number information, or Allocation frequency resource information is included.
- encoding unit 102 extracts an output codeword that matches the encoding rate included in the control information received from control unit 110 from the codeword held in the circular buffer and outputs the codeword to modulation unit 103. . Based on the control information received from control unit 110, encoding unit 102 performs processing related to retransmission preparation, retransmission, and new data transmission (including processing for removing codewords related to previous transmission data from the circular buffer). Details of the processing in the encoding unit 102 will be described later.
- Modulation section 103 generates a data symbol by modulating the codeword received from encoding section 102 with the modulation multi-value number included in the control signal received from control section 110, and provides the obtained data symbol to multiplexing section 104. Output.
- the multiplexing unit 104 multiplexes the data symbol received from the modulation unit 103, the control information received from the control unit 110, and the pilot signal to form a multiplexed signal that is a baseband signal.
- the data symbol is arranged at the allocated frequency indicated by the allocated frequency resource information included in the control information received from the control unit 110.
- the transmission RF unit 105 converts the frequency of the multiplexed signal and transmits the obtained RF signal via the antenna 106.
- the reception RF unit 107 receives a control signal (including allocation information or an ACK / NACK signal) transmitted from the base station 200, which will be described later, via the antenna 106, and converts the frequency of the received signal to generate a baseband signal. Get. This baseband signal is output to demodulation section 108.
- a control signal including allocation information or an ACK / NACK signal
- Demodulation section 108 demodulates the control signal included in the baseband signal received from reception RF section 107, and outputs the demodulated control signal to decoding section 109.
- the decoding unit 109 decodes the demodulated control signal and outputs the obtained control information to the control unit 110.
- the control unit 110 specifies the coding rate, the modulation multi-level number, the allocated frequency resource, and the ACK / NACK information included in the control information received from the decoding unit 109. In addition, the control unit 110 determines whether to execute each process of retransmission preparation, retransmission execution determination, retransmission, and new data transmission based on the specified ACK / NACK information, and control information corresponding to the determination result Is output to the encoding unit 102. Also, the coding rate of the specified control information is output to the encoding unit 102, the modulation multi-level number is output to the modulation unit 103, and the allocated frequency resource is output to the multiplexing unit 104.
- FIG. 5 is a block diagram showing a configuration of base station 200 according to Embodiment 1 of the present invention.
- the base station 200 includes an antenna 201, a reception RF unit 202, a separation unit 203, a demodulation unit 204, a decoding unit 205, an error detection unit 206, a channel quality estimation unit 207, a scheduler 208, A control information generation unit 209, an encoding unit 210, a modulation unit 211, and a transmission RF unit 212.
- the reception RF unit 202 receives a data signal transmitted from the terminal 100 via the antenna 201, and obtains a baseband signal by frequency-converting the received data signal.
- the baseband signal is output to the separation unit 203.
- Separation section 203 separates the baseband signal received from reception RF section 202 into data symbols and reception pilot signals. Further, demultiplexing section 203 outputs data symbols corresponding to allocated frequency resource information included in the allocation information received from scheduler 208 to demodulation section 204, and outputs a received pilot signal to channel quality estimation section 207.
- the demodulation unit 204 demodulates the data symbol received from the separation unit 203 according to the modulation multilevel number information included in the allocation information received from the scheduler 208.
- the decoding unit 205 obtains a decoded bit sequence by performing error correction decoding on the demodulation result received from the demodulation unit 204 for each TTI based on the coding rate information included in the allocation information received from the scheduler 208.
- the decoded bit string (received data) thus obtained is held in a memory (not shown) provided in the decoding unit 205 and is output to the error detection unit 206.
- the decoding result of the current TTI in the TTI bundle is used for decoding the codeword transmitted in the next TTI. Therefore, in the TTI bundle, the error rate of the codeword transmitted by the TTI becomes lower as the TTI becomes later. Also, the decoding unit 205 discards received data already stored in the memory only when receiving an ACK signal from the error detection unit 206.
- the error detection unit 206 performs error detection (CRC) on the decoded bit string received from the decoding unit 205 for each TTI.
- CRC error detection
- the error detection unit 206 generates a NACK signal as a response signal when there is an error in the decoded bit string as a result of error detection, and generates an ACK signal as a response signal when there is no error in the decoded bit string.
- the ACK / NACK signal thus generated is output to decoding section 205, scheduler 208, and control information generation section 209. Further, when there is no error in the decoded bit string, the error detection unit 206 outputs the decoded bit string as a received bit string.
- the channel quality estimation unit 207 estimates the channel quality (SINR: Signal-to-Interference and Noise power Ratio) from the received pilot signal.
- SINR Signal-to-Interference and Noise power Ratio
- the SINR estimate is output to the scheduler 208.
- the scheduler 208 generates allocation information based on the SINR estimation value received from the channel quality estimation unit 207 and the ACK / NACK signal received from the error detection unit 206.
- This allocation information includes modulation multilevel number information, coding rate information, and allocation resource information.
- This allocation information is output to the control information generation unit 209, the separation unit 203, the demodulation unit 204, and the decoding unit 205. The scheduling of retransmission data by the scheduler 208 will be described later.
- the control information generation unit 209 receives the ACK / NACK signal from the error detection unit 206. Then, when data transmission using the TTI-bundling technique is performed, the control information generation unit 209 sequentially transmits ACK / NACK signals related to codewords transmitted with a plurality of TTIs in the TTI bundle according to the detection timing. Send.
- the control information generation unit 209 receives the ACK / NACK signal related to the codeword transmitted in at least one other TTI. The data is sequentially transmitted according to the detection timing.
- the control information generation unit 209 generates a control signal frame by combining the ACK / NACK signal with the allocation information received from the scheduler 208, and transmits this frame via the encoding unit 210, the modulation unit 211, and the transmission RF unit 212. To do.
- the control signal frame generated by the control information generation unit 209 is encoded by the encoding unit 210, modulated by the modulation unit 211, frequency-converted by the transmission RF unit 212, and then transmitted via the antenna 201. .
- FIG. 6 is a diagram for explaining operations of the terminal 100 and the base station 200. Hereinafter, the operations of the terminal 100 and the base station 200 will be described with reference to FIG.
- the terminal 100 bundles TTIs 0 to 2 and transmits data. That is, in terminal 100, coding section 102 extracts an output codeword that matches the coding rate included in the control information received from control section 110 from the codeword held in the circular buffer and outputs the codeword to modulation section 103.
- FIG. 7 is a diagram for explaining a state in which the code word is stored in the circular buffer and a method for reading the code word from the circular buffer (at the time of initial transmission).
- the circular buffer is composed of 96 columns and stores codewords.
- S in the left part is information bits to which CRC parity is added (that is, systematic bits), and P1 and P2 (64-column structure) in the right part are parity generated by turbo coding. Is a bit.
- the systematic bit side is defined as the front, and the parity bit side is defined as the back.
- the encoding unit 102 reads a code word of a predetermined length backward from a predetermined reading start position as data 1 transmitted by TTI 0 and outputs the code word to the modulation unit 103.
- the predetermined read start position (RV0) is the third column from the left of the circular buffer (FIG. 7).
- the predetermined length is 64 columns of the circular buffer. Therefore, data 1 corresponds to the third to 66th columns of the circular buffer.
- the encoding unit 102 uses the next column after the last column read out with the data 1 as a reading start position, reads out a codeword of a predetermined length (corresponding to the data 2 in FIG. 7) backward, and modulates the unit 103. Output to.
- the last column of the circular buffer is reached before the predetermined length of reading is completed, the reading is continued from the first column of the circular buffer. Therefore, data 2 corresponds to the 67th to 96th columns and the 1st to 34th columns of the circular buffer.
- the encoding unit 102 reads the code word (corresponding to the data 3 in FIG. 7) of a predetermined length in the backward direction, using the next column of the last column read out with the data 2 as the reading start position, and the modulation unit 103. Output to. Data 3 corresponds to the 35th to 96th columns and the 1st to 2nd columns of the circular buffer.
- RV (Redundancy) Version) is instruction information for specifying from which position in the circular buffer the code word string is read.
- RV0 is defined as the third column, RV1 as the 27th column, RV2 as the 51st column, and RV3 as the 75th column. And RV0 is used at the time of the first transmission.
- the plurality of code words read from the circular buffer in this way are transmitted as TTI bundles of TTI 0 to 2 and received by the base station 200 as shown in FIG.
- error detection section 206 detects errors in received data for each TTI.
- the control information generation unit 209 adds the error detection result (that is, the ACK / NACK signal) related to the codeword transmitted at the end TTI in the TTI bundle to at least another codeword transmitted at another TTI.
- error detection results are sequentially transmitted according to the detection timing.
- the ACK / NACK signal related to the codeword transmitted in TTI2 which is the tail TTI the ACK / NACK signal related to the codeword transmitted in TTI0 which is the head TTI is transmitted.
- the ACK / NACK signal transmitted at the head TTI is used as a trigger for retransmission preparation
- the ACK / NACK signal transmitted at the tail TTI is used as a retransmission execution determination criterion. That is, as will be described later, retransmission is executed by terminal 100 only when a NACK signal is transmitted in both the head TTI and tail TTI. Therefore, the scheduler 208 of the base station 200 transmits resources for retransmission using the TTI bundle by the terminal 100 (that is, in the retransmission scheduled sections TTI8 to 10 only when the NACK signal is transmitted in both the head TTI and the tail TTI. Ensure frequency resources).
- the terminal 100 determines whether to start retransmission preparation for the entire TTI bundle based on the TTI0 ACK / NACK signal transmitted from the base station 200, and prepares based on the TTI2 ACK / NACK signal. It is determined whether or not to retransmit the code word of the entire TTI bundle.
- control section 110 determines whether or not to cause encoding section 102 to start retransmission preparation for the entire TTI bundle based on the ACK / NACK signal of TTI0.
- control unit 110 causes encoding unit 102 to start preparation for retransmission of the entire TTI bundle.
- control unit 110 causes encoding unit 102 to prepare for new data transmission.
- control section 110 determines whether or not to execute retransmission of codewords of the entire TTI bundle prepared in encoding section 102 based on the ACK / NACK signal of TTI2. Then, when an ACK signal is transmitted from base station 200 using TTI2, control unit 110 does not cause encoding unit 102 to retransmit the codeword for the entire TTI bundle. On the other hand, when the NACK signal is transmitted from the base station 200 in TTI2, the control unit 110 causes the encoding unit 102 to retransmit the codeword of the entire TTI bundle (see FIG. 8).
- FIG. 9 is a diagram for explaining a state in which a code word is stored in a circular buffer and a method for reading a code word from the circular buffer (at the time of retransmission).
- the encoding unit 102 extracts a code word using a position different from the previous transmission as a reading start position during retransmission, and outputs the code word to the modulation unit 103.
- RV2 is the read start position for the first retransmission.
- decoding section 205 decodes the codeword mapped to the TTI bundle for each TTI, and error detection section 206 detects each decoding result as an error.
- the control information generation unit 209 detects, in addition to the error detection result information related to the codeword transmitted in the last TTI in the TTI bundle, the error detection result information related to the codeword transmitted in another other TTI. Transmit sequentially according to the timing.
- the terminal 100 can use the error detection result at the tail TTI as a criterion for retransmission execution, it prevents unnecessary retransmission of sending retransmission data of a TTI bundle with a conventional NACK signal of only the head TTI. can do.
- the base station 200 transmits, in addition to the error detection result information related to the code word transmitted at the tail TTI in the TTI bundle, at least another code transmitted by another TTI.
- the error detection result information relating to the word is sequentially transmitted according to the detection timing.
- the terminal 100 can use an error detection result in a TTI other than the tail TTI as a trigger for starting retransmission preparation, retransmission using the TTI bundle can be executed. That is, according to the present embodiment, it is possible to realize base station 200 that improves error characteristics during retransmission while preventing unnecessary retransmission.
- the other TTI is preferably the head TTI. By doing so, similar to the previous transmission, retransmission using the entire TTI bundle becomes possible. If the other TTI is other than the head TTI, retransmission from the other TTI to the tail TTI is performed.
- the error detection result related to the code word transmitted at the end TTI is described as being transmitted without fail.
- the base station 200 may transmit the error detection result related to the codeword transmitted in the first TTI and the second TTI in the TTI bundle.
- terminal 100 can use the first TTI error detection result transmitted earlier as a trigger for retransmission preparation start, and can use the second TTI error detection result as a retransmission execution determination criterion. .
- Embodiment 2 the base station transmits all the error detection results obtained for the codewords mapped to the TTI bundle.
- the basic configuration of the terminal and the base station according to the present embodiment is the same as the configuration of the terminal and the base station described in Embodiment 1. Therefore, the terminal and base station according to the present embodiment will also be described using FIG. 4 and FIG. However, the operations of the control unit 110 of the terminal 100 and the scheduler 208 and the control information generation unit 209 of the base station 200 are different from those of the first embodiment.
- control section 110 performs each process of retransmission preparation, retransmission execution determination, retransmission, and new data transmission based on the specified ACK / NACK information. It is determined whether or not to execute, and control information corresponding to the determination result is output to the encoding unit 102.
- Embodiment 2 all of the error detection results obtained for the codeword mapped to the TTI bundle are transmitted from the base station 200. Therefore, Embodiment 1 and Embodiment 2 are the same in that the error detection result of the head TTI is used as a trigger for starting retransmission preparation, and the error detection result of the tail TTI is used as a retransmission execution determination criterion. On the other hand, the difference is that the TTI error detection result in the meantime is used as a trigger for stopping retransmission preparation.
- control unit 110 causes the encoding unit 102 to start preparation for retransmission of the entire TTI bundle.
- the control unit 110 stops the retransmission preparation already started at that time in the coding unit 102 To prepare for new data transmission.
- control information generation section 209 sequentially transmits ACK / NACK signals related to codewords transmitted in each TTI according to detection timing.
- the scheduler 208 transmits an ACK signal in a TTI bundle
- the scheduler 208 releases resources related to retransmission of the TTI bundle.
- FIG. 10 is a diagram for explaining operations of terminal 100 and base station 200 according to Embodiment 2.
- the terminal 100 bundles TTIs 0 to 2 and transmits data.
- the error detection unit 206 detects errors in received data for each TTI. Then, the control information generation unit 209 sequentially transmits the error detection result of each TTI according to the detection timing. In FIG. 10, a NACK signal is transmitted in TTI0, and an ACK signal is transmitted in TTI1 and TTI2.
- control unit 110 causes encoding unit 102 to start retransmission preparation for the entire TTI bundle.
- the control unit 110 causes the encoding unit 102 to stop the retransmission preparation already started and prepare for new data transmission.
- the terminal 100 can stop the retransmission preparation at the time of receiving the ACK signal without waiting for the ACK / NACK signal of the last TTI from the base station 200, so that the power consumption for the retransmission preparation can be reduced. .
- the buffer area reserved for retransmission data can be released at an early stage.
- the base station transmits an ACK / NACK signal using only the last TTI in the TTI bundle.
- the terminal When the terminal transmits data in the TTI bundle, the terminal automatically enters preparation for retransmission, and determines whether or not to perform retransmission based on the ACK / NACK signal of the last TTI.
- the basic configuration of the terminal and the base station according to the present embodiment is the same as the configuration of the terminal and the base station described in Embodiment 1. Therefore, the terminal and base station according to the present embodiment will also be described using FIG. 4 and FIG. However, the operations of the control unit 110 of the terminal 100, the scheduler 208 of the base station 200, and the control information generation unit 209 are different from those of the first embodiment.
- control section 110 executes each process of retransmission execution determination, retransmission, and new data transmission based on the specified ACK / NACK information.
- the control information according to the determination result is output to the encoding unit 102.
- control unit 110 causes encoding unit 102 to start retransmission preparation when data is transmitted in a TTI bundle. Then, the control unit 110 determines whether or not to perform retransmission based on the error detection result of the tail TTI transmitted from the base station 200.
- control information generation section 209 transmits to terminal 100 only the ACK / NACK signal related to the codeword transmitted at the end TTI for the TTI bundle.
- the scheduler 208 releases resources related to retransmission of the TTI bundle only when an ACK signal is transmitted with the tail TTI.
- FIG.11 and FIG.12 is a figure with which it uses for operation
- FIG.11 and FIG.12 is a figure with which it uses for operation
- FIG.11 and FIG.12 is a figure with which it uses for operation
- FIG.11 and FIG.12 is a figure with which it uses for operation
- control section 110 causes encoding section 102 to start preparation for retransmission of the entire TTI bundle.
- the error detection unit 206 detects errors in received data for each TTI. Then, the control information generation unit 209 transmits only the error detection result of the tail TTI to the terminal 100.
- terminal 100 it is determined whether or not to perform retransmission based on the error detection result of the tail TTI transmitted from base station 200.
- the control unit 110 since the NACK signal is transmitted from the base station 200, the control unit 110 causes the encoding unit 102 to retransmit the entire TTI bundle.
- control section 110 causes encoding section 102 to prepare for new data transmission.
- the base station 200 transmits only the ACK / NACK signal related to the codeword transmitted in the last TTI to the terminal 100.
- the same effect as in Embodiment 3 can be obtained.
- control information generation unit 209 transmits an ACK / NACK signal to the terminal 100 only with a TTI in which no error is detected for the first time with respect to one TTI bundle.
- terminal 100 uses this ACK / NACK signal as a criterion for performing retransmission.
- terminal 100 can receive an ACK signal at an early stage as compared with Embodiment 3, preparation for retransmission can be stopped at an early stage. Therefore, it is possible to reduce the power consumption required for retransmission preparation.
- the terminal 100 can move to preparation for new data transmission, so that the buffer area reserved for retransmission data can be released at an early stage.
- Embodiments 1 to 3 it has been described that decoding and error detection are performed for each TTI, but decoding and error detection may be performed only at the timing of transmitting an ACK / NACK signal.
- Each functional block used in the description of the first to third embodiments is typically realized as an LSI that is an integrated circuit. These may be individually made into one chip, or may be made into one chip so as to include a part or all of them.
- the name used here is LSI, but it may also be called IC, system LSI, super LSI, or ultra LSI depending on the degree of integration.
- the method of circuit integration is not limited to LSI, and implementation with a dedicated circuit or a general-purpose processor is also possible.
- An FPGA Field Programmable Gate Array
- a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used.
- the wireless communication apparatus and error detection result feedback method of the present invention are useful for improving system throughput by preventing unnecessary retransmission without degrading the quality of retransmission data.
Abstract
Description
[端末の構成]
図4は、本発明の実施の形態1に係る端末100の構成を示すブロック図である。図4において、端末100は、CRC部101と、符号化部102と、変調部103と、多重部104と、送信RF部105と、アンテナ106と、受信RF部107と、復調部108と、復号部109と、制御部110とを有する。
図5は、本発明の実施の形態1に係る基地局200の構成を示すブロック図である。図5において、基地局200は、アンテナ201と、受信RF部202と、分離部203と、復調部204と、復号部205と、誤り検出部206と、回線品質推定部207と、スケジューラ208と、制御情報生成部209と、符号化部210と、変調部211と、送信RF部212とを有する。
図6は、端末100及び基地局200の動作説明に供する図である。以下、図6を参照しつつ、端末100及び基地局200の動作について説明する。
図6に示すように、端末100は、TTI0~2を束ねてデータ送信する。すなわち、端末100において、符号化部102が、制御部110から受け取る制御情報に含まれる符号化率に合った出力符号語をサーキュラーバッファに保持された符号語から抜き出して変調部103へ出力する。
基地局200において、誤り検出部206は、受信データをTTIごとに誤り検出する。
後述するように、端末100では、先頭TTIで送信されるACK/NACK信号が再送準備のトリガとして利用され、さらに、末尾TTIで送信されるACK/NACK信号が再送実行判断基準として利用される。すなわち、後述するように、先頭TTI及び末尾TTIの両方でNACK信号が送信されるときにのみ端末100で再送が実行される。従って、基地局200のスケジューラ208は、先頭TTI及び末尾TTIの両方でNACK信号を送信する場合にのみ、端末100によるTTI束を用いた再送のためのリソース(つまり、再送予定区間TTI8~10における周波数リソース等)を確保しておく。
端末100は、基地局200から送信されたTTI0のACK/NACK信号に基づいてTTI束全体の再送準備を開始するか否かを判断し、TTI2のACK/NACK信号に基づいて、準備しておいたTTI束全体の符号語の再送を実行するか否かを判断する。
図9は、符号語がサーキュラーバッファに格納されている状態、及び、サーキュラーバッファからの符号語読み出し方法(再送時)の説明に供する図である。
ここで、TTI束における末尾TTIで送信された符号語に係る誤り検出結果を基地局200が端末100に送信する態様も考えられる(図3参照)。こうすることでも、無駄な再送を防止することができる。しかしながら、この態様では、端末100は、再送時には、末尾TTIに対応する再送予定区間でしか再送することができない。すなわち、端末100は、TTI束を用いて再送することができない。なぜならば、末尾TTIでNACK信号を受け取ってから、末尾TTI以外のTTIに対応する再送予定区間での再送準備を開始しても当該再送予定区間には間に合わないからである。従って、TTI-bundling技術を用いた再送を実行することができないので、データ受信側における誤り特性が劣化してしまう。
実施の形態2では、基地局が、TTI束にマッピングされた符号語について得られた誤り検出結果のすべてを送信する。本実施の形態に係る端末及び基地局の基本構成は、実施の形態1で説明された端末及び基地局の構成と同じである。従って、本実施の形態に係る端末及び基地局についても、図4及び図5を用いて説明する。ただし、端末100の制御部110、並びに、基地局200のスケジューラ208及び制御情報生成部209の動きが実施の形態1と異なる。
実施の形態3では、基地局が、TTI束における末尾TTIのみでACK/NACK信号を送信する。そして、端末は、TTI束でデータを送信すると、自動的に再送の準備に入り、末尾TTIのACK/NACK信号に基づいて再送を実行するか否かを判断する。本実施の形態に係る端末及び基地局の基本構成は、実施の形態1で説明された端末及び基地局の構成と同じである。従って、本実施の形態に係る端末及び基地局についても、図4及び図5を用いて説明する。ただし、端末100の制御部110、並びに、基地局200のスケジューラ208及び制御情報生成部209の動きが実施の形態1と異なる。
(1)実施の形態3において、基地局200は、末尾TTIで送信された符号語に係るACK/NACK信号のみを端末100に送信している。しかしながら、基地局200が、末尾TTIの変わりに、TTI束において初めて誤りが検出されないTTIでのみACK/NACK信号を送信する態様としても、実施の形態3と同様の効果を得ることができる。
Claims (4)
- 1つの送信データを符号化した符号語が複数のTTIからなるTTI束にマッピングされた無線信号を受信する無線通信装置であって、
前記TTI束にマッピングされた符号語をTTIごとに復号する復号手段と、
各復号結果を誤り検出する誤り検出手段と、
前記TTI束における末尾TTIで送信された符号語に係る誤り検出結果情報の他に、少なくとももう1つの他TTIで送信された符号語に係る誤り検出結果情報を、検出タイミングに応じて順次送信する送信手段と、
を具備する無線通信装置。 - 前記他TTIは、前記TTI束における末尾TTIを除くすべてのTTIである、
請求項1に記載の無線通信装置。 - 前記他TTIは、前記TTI束における先頭TTIである、
請求項1に記載の無線通信装置。 - 1つの送信データを符号化した符号語が複数のTTIからなるTTI束にマッピングされた無線信号を受信するステップと、
前記TTI束にマッピングされた符号語をTTIごとに復号するステップと、
各復号結果を誤り検出するステップと、
前記TTI束における末尾TTIで送信された符号語に係る誤り検出結果情報の他に、少なくとももう1つの他TTIで送信された符号語に係る誤り検出結果情報を、検出タイミングに応じて順次送信するステップと、
を具備する誤り検出結果フィードバック方法。
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/062,482 US20110173519A1 (en) | 2008-09-12 | 2009-09-11 | Wireless communication apparatus and error detection result feedback method |
JP2010528658A JPWO2010029764A1 (ja) | 2008-09-12 | 2009-09-11 | 無線通信装置及び誤り検出結果フィードバック方法 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2008235358 | 2008-09-12 | ||
JP2008-235358 | 2008-09-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010029764A1 true WO2010029764A1 (ja) | 2010-03-18 |
Family
ID=42005028
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2009/004528 WO2010029764A1 (ja) | 2008-09-12 | 2009-09-11 | 無線通信装置及び誤り検出結果フィードバック方法 |
Country Status (3)
Country | Link |
---|---|
US (1) | US20110173519A1 (ja) |
JP (1) | JPWO2010029764A1 (ja) |
WO (1) | WO2010029764A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2011061388A (ja) * | 2009-09-08 | 2011-03-24 | Ntt Docomo Inc | 無線基地局及び移動通信方法 |
JP2017537508A (ja) * | 2014-10-27 | 2017-12-14 | クアルコム,インコーポレイテッド | 信頼できる低レイテンシ通信のためのファウンテンharq |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NO2648356T3 (ja) * | 2007-06-18 | 2018-09-01 | ||
WO2009126902A2 (en) * | 2008-04-11 | 2009-10-15 | Interdigital Patent Holdings, Inc. | Methods for transmission time interval bundling in the uplink |
WO2010088950A1 (en) * | 2009-02-03 | 2010-08-12 | Nokia Siemens Networks Oy | Apparatus, method and article of manufacture |
JP5590141B2 (ja) * | 2010-11-12 | 2014-09-17 | 富士通株式会社 | 基地局、移動局、制御方法および通信システム |
US9398579B2 (en) * | 2013-05-03 | 2016-07-19 | Qualcomm Incorporated | Systems and methods for downlink frequency domain multiplexing transmissions |
JPWO2020217612A1 (ja) * | 2019-04-23 | 2020-10-29 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008503183A (ja) * | 2004-06-10 | 2008-01-31 | インターデイジタル テクノロジー コーポレーション | データ伝送パラメータを動的に調整しh−arq処理を制御する方法および装置 |
JP2008160742A (ja) * | 2006-12-26 | 2008-07-10 | Fujitsu Ltd | 移動通信装置 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7813754B2 (en) * | 2004-06-17 | 2010-10-12 | Ntt Docomo, Inc. | Transfer rate control method, transmission power control method, transmission power ratio control method, mobile communication system, mobile station, and radio base station |
KR20060006725A (ko) * | 2004-07-16 | 2006-01-19 | 삼성전자주식회사 | 향상된 상향링크 전용채널을 지원하는 이동통신시스템에서자율전송을 위한 파라미터 결정 방법 및 장치 |
WO2006024321A1 (en) * | 2004-08-31 | 2006-03-09 | Telefonaktiebolaget Lm Ericsson (Publ) | Communication device |
US7382747B2 (en) * | 2004-09-16 | 2008-06-03 | Lucent Technologies Inc. | Selecting a subset of automatic request retransmission processes |
KR100651548B1 (ko) * | 2004-11-05 | 2006-11-29 | 삼성전자주식회사 | 상향링크 패킷 데이터 서비스를 지원하는 이동통신시스템에서 단말 식별자를 이용하여 상향링크 데이터전송을 스케쥴링하는 방법 및 장치 |
US9882683B2 (en) * | 2006-09-28 | 2018-01-30 | Telefonaktiebolaget Lm Ericsson (Publ) | Autonomous transmission for extended coverage |
US7778151B2 (en) * | 2006-10-03 | 2010-08-17 | Texas Instruments Incorporated | Efficient scheduling request channel for wireless networks |
CN101562838B (zh) * | 2008-04-15 | 2011-06-29 | 创新音速有限公司 | 改善传输时间间隔集束传输的方法及通讯装置 |
WO2009132169A1 (en) * | 2008-04-25 | 2009-10-29 | Interdigital Patent Holdings, Inc. | Methods to implement transmission time interval bundling |
-
2009
- 2009-09-11 WO PCT/JP2009/004528 patent/WO2010029764A1/ja active Application Filing
- 2009-09-11 JP JP2010528658A patent/JPWO2010029764A1/ja active Pending
- 2009-09-11 US US13/062,482 patent/US20110173519A1/en not_active Abandoned
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008503183A (ja) * | 2004-06-10 | 2008-01-31 | インターデイジタル テクノロジー コーポレーション | データ伝送パラメータを動的に調整しh−arq処理を制御する方法および装置 |
JP2008160742A (ja) * | 2006-12-26 | 2008-07-10 | Fujitsu Ltd | 移動通信装置 |
Non-Patent Citations (2)
Title |
---|
ERICSSON, 3GPP TSG-RAN WG2 #62 TDOC R2-082149, 3GPP, 5 May 2008 (2008-05-05), pages 1 - 6 * |
NOKIA CORPORATION ET AL., 3GPP TSG-RAN WG2 MEETING #62 BIS R2-083107, 3GPP, 30 June 2008 (2008-06-30) * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2011061388A (ja) * | 2009-09-08 | 2011-03-24 | Ntt Docomo Inc | 無線基地局及び移動通信方法 |
JP2017537508A (ja) * | 2014-10-27 | 2017-12-14 | クアルコム,インコーポレイテッド | 信頼できる低レイテンシ通信のためのファウンテンharq |
US11489646B2 (en) | 2014-10-27 | 2022-11-01 | Qualcomm Incorporated | Fountain harq for reliable low latency communication |
Also Published As
Publication number | Publication date |
---|---|
US20110173519A1 (en) | 2011-07-14 |
JPWO2010029764A1 (ja) | 2012-02-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20220321282A1 (en) | Harq handling for nodes with variable processing times | |
WO2010029763A1 (ja) | 中継装置及び無線通信システム | |
CN108292976B (zh) | 电信装置和方法 | |
CN110463109B (zh) | 发送删余信号的方法、设备和存储介质 | |
KR101634177B1 (ko) | 데이터 패킷의 처리 및 전송 방법 | |
US8667357B2 (en) | Method for conducting HARQ with a wireless communications system | |
JP3522728B2 (ja) | Harq方式を使用するデータ通信システムのデータ伝送装置及び方法 | |
WO2010029764A1 (ja) | 無線通信装置及び誤り検出結果フィードバック方法 | |
US10972228B2 (en) | Base station device, user equipment, wireless communication system, and communication method | |
KR101631714B1 (ko) | 터보 복호기를 위한 반복 복호의 제어 방법 및 장치 | |
KR20180013171A (ko) | 이동 통신 시스템에서 harq 프로세스 관리 방법 및 장치 | |
CN106899390B (zh) | 基于harq传输的方法、装置及系统 | |
RU2554527C2 (ru) | Способы и устройства в телекоммуникационной системе | |
US20180167171A1 (en) | HARQ Feedback Scheme for 5G New Radio | |
WO2018171737A1 (zh) | 一种数据传输方法和相关设备 | |
JP2010016824A (ja) | 自動再送コントローラ及び再送ブロック再結合装置 | |
CN108521316B (zh) | 一种混合自动重传请求方法及装置 | |
JP2006253980A (ja) | 受信方法および受信装置 | |
JP2010098741A (ja) | 送信データ生成装置及び受信機 | |
CN101416434A (zh) | 用于改进的混合自动重传请求的方法、接收机和发射机 | |
US10931405B2 (en) | Relaying method and device and destination with feedback in an OMAMRC system | |
TWI669926B (zh) | 用於5g新無線電之混合自動重傳請求回授方案 | |
JPWO2009019817A1 (ja) | 無線通信装置、無線通信システム及び無線通信方法 | |
US8599760B2 (en) | Error propagation protection in non-binary multiple ACK/NACKS | |
WO2004102864A1 (en) | A method, arrangement, node and mobile unit for improved transmission between two units of a telecommunication system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 09812913 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010528658 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13062482 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 09812913 Country of ref document: EP Kind code of ref document: A1 |