CN108322293B - Log-likelihood ratio determination method for HARQ, HARQ feedback method and apparatus - Google Patents

Abstract

A method for determining the log-likelihood ratio of HARQ, a HARQ feedback method and a device thereof, the method comprises receiving retransmission data, calculating to obtain system bit log-likelihood ratio and check bit log-likelihood ratio according to the retransmission data, the retransmission data is determined according to the data with error received for the last times, obtaining a second system bit log-likelihood ratio and a second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are obtained after the data with error received for the last times is subjected to channel decoding, combining the system bit log-likelihood ratio and the second system bit log-likelihood ratio, and combining the check bit log-likelihood ratio and the second check bit log-likelihood ratio.

Description

Log-likelihood ratio determination method for HARQ, HARQ feedback method and apparatus

technical field

The present invention relates to the field of communication technologies, and in particular, to a method for determining a log-likelihood ratio for HARQ, a HARQ feedback method, and an apparatus.

Background technique

The traditional Hybrid Automatic Repeat Request (HARQ) technology combines Forward Error Correction (FEC) and Automatic Repeat Request (ARQ) with the advantages of FEC and ARQ. To a certain extent, it can improve data throughput, improve data transmission reliability and improve system service quality.

In the HARQ mechanism, the sender first performs FEC encoding on the source data and sends it, and then the receiver decodes the received data frame through FEC decoding. If the decoding is correct, an acknowledgment character (Acknowledgement, ACK) is fed back to the sender; if the decoding is wrong, a non-acknowledgement character (Negative Acknowledgement, NACK) is fed back to the sender. Then the sender receives the information fed back by the receiver. If the feedback is ACK, the next data transmission is performed. If the feedback is NACK, ARQ retransmission is started to retransmit the data frame with an FEC decoding error. Finally, the receiving end adopts separate FEC decoding and retransmitting data frames according to different retransmission mechanisms, and performs FEC decoding after combining the retransmitted data frames. Since FEC can correct common error conditions, it can reduce the frequency of ARQ retransmissions, thereby increasing the data throughput of the system. When an uncommon error occurs, the receiver requires the sender to retransmit the information, thereby increasing the reliability of information transmission. The key of HARQ is to store, request retransmission, and combine and demodulate. The traditional ARQ technology simply discards the erroneous data and does not store it, so there is no merging process, no diversity gain, and often requires too many retransmissions and too long waiting. Compared with the traditional ARQ technology, the existing HARQ technology combines ARQ and FEC technology to improve the accuracy of information transmission of the system to a certain extent.

However, with the development of communication technology, the existing HARQ still cannot meet the requirements in terms of information transmission accuracy.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is how to improve the accuracy of information transmission.

In order to solve the above-mentioned technical problems, an embodiment of the present invention provides a method for determining a log-likelihood ratio for HARQ, and the method for determining a log-likelihood ratio for HARQ includes:

Receive the retransmitted data, and calculate the first systematic bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmitted data, and the retransmitted data is determined according to the last received erroneous data Obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are the The erroneous data received last time is obtained after channel decoding; the first system bit log-likelihood ratio and the second system bit log-likelihood ratio are combined, and the first check bit The log likelihood ratio is combined with the second check bit log likelihood ratio.

Optionally, the method for determining the log-likelihood ratio further includes: combining the result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio, and the first check bit. Perform channel decoding on the combined result of the log-likelihood ratio and the second check bit log-likelihood ratio to obtain the third system bit log-likelihood ratio; The third systematic bit log-likelihood ratio is combined to obtain the fourth systematic bit log-likelihood ratio.

In order to solve the above technical problem, an embodiment of the present invention further discloses a HARQ feedback method, and the HARQ feedback method includes:

Receive the retransmitted data, and calculate the first systematic bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmitted data, and the retransmitted data is determined according to the last received erroneous data Obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are the The erroneous data received last time is obtained after channel decoding; the first system bit log-likelihood ratio and the second system bit log-likelihood ratio are combined, and the first check bit combining the log-likelihood ratio and the second check bit log-likelihood ratio; combining the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, and the performing channel decoding on the combined result of the log-likelihood ratio of the first check bit and the log-likelihood ratio of the second check bit to obtain a third-system bit-log-likelihood ratio; using the third-system bit-log-likelihood ratio The likelihood ratio generates a third check bit log-likelihood ratio; and a symbol is generated according to the third systematic bit log-likelihood ratio and the third check bit log-likelihood ratio for feedback.

Optionally, the HARQ feedback method further includes: combining the bit log-likelihood ratio of the second system and the bit log-likelihood ratio of the third system to obtain a fourth system bit log-likelihood ratio, for determining feedback information.

Optionally, the combined result of the bit log-likelihood ratio of the first system and the bit log-likelihood ratio of the second system, and the first check bit log-likelihood ratio and the second check After performing channel decoding on the combined result of the bit log-likelihood ratio, the method further includes: storing the bit log-likelihood ratio of the third system.

Optionally, the combined result of the bit log-likelihood ratio of the first system and the bit log-likelihood ratio of the second system, and the first check bit log-likelihood ratio and the second check After performing channel decoding on the combined result of the bit log-likelihood ratio, the method further includes: storing the third check bit log-likelihood ratio.

Optionally, the HARQ feedback method further includes: when the number of retransmissions of the retransmitted data reaches a maximum number of retransmissions, clearing the retransmitted data and the stored content.

Optionally, the HARQ feedback method further includes: combining the symbols with subsequently received retransmission data to continue channel decoding until the maximum number of retransmissions is reached.

Optionally, the HARQ feedback method further includes: if the feedback information is a negative acknowledgement, continuing to receive subsequent retransmission data, otherwise receiving new data.

In order to solve the above technical problem, the embodiment of the present invention also discloses a log-likelihood ratio determination device for HARQ, the log-likelihood ratio determination device for HARQ includes: a calculation module, suitable for receiving retransmission data, And the first system bit log-likelihood ratio and the first check bit log-likelihood ratio are obtained by calculating according to the retransmission data, and the retransmission data is determined according to the data of the last received error; the acquisition module, suitable for For obtaining the second systematic bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are the The last received error data is obtained after channel decoding; the first combining module is adapted to combine the bit log-likelihood ratio of the first system and the bit log-likelihood ratio of the second system, and combine the The log-likelihood ratio of the first parity bit is combined with the log-likelihood ratio of the second parity bit.

Optionally, the log-likelihood ratio determining apparatus further includes: a channel decoding module adapted to combine the result of the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, and Channel decoding is performed on the combined result of the log-likelihood ratio of the first check bit and the log-likelihood ratio of the second check bit to obtain the log-likelihood ratio of the third system bit; the second combining module, adapted to The second systematic bit log likelihood ratio and the third systematic bit log likelihood ratio are combined to obtain a fourth systematic bit log likelihood ratio.

In order to solve the above technical problems, an embodiment of the present invention further discloses a HARQ feedback device, and the HARQ feedback device includes:

A calculation module, adapted to receive retransmission data, and calculate and obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, the retransmission data is based on the last received data The wrong data is determined; the obtaining module is adapted to obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio; The log-likelihood ratio of the check bit is obtained after the last received erroneous data is decoded by the channel; the first combining module is adapted to combine the log-likelihood ratio of the first system bit with the second system bit The log-likelihood ratio is combined, and the log-likelihood ratio of the first check bit is combined with the log-likelihood ratio of the second check bit; the channel decoding module is suitable for the first check bit log-likelihood ratio. The combined result of the log-likelihood ratio of the systematic bits and the log-likelihood ratio of the second systematic bits, and the combined result of the log-likelihood ratio of the first check bits and the log-likelihood ratio of the second check bits are channeled Decoding, to obtain the third system bit log-likelihood ratio; the check bit log-likelihood ratio generating module utilizes the third system bit log-likelihood ratio to generate the third check bit log-likelihood ratio; A symbol generation module adapted to generate symbols for feedback according to the third systematic bit log-likelihood ratio and the third check bit log-likelihood ratio.

Optionally, the HARQ feedback apparatus further includes: a second combining module, adapted to combine the bit log-likelihood ratio of the second system and the bit log-likelihood ratio of the third system to obtain a fourth system. Bit log-likelihood ratio for determining feedback information.

Optionally, the HARQ feedback apparatus further includes: a first storage module, adapted to store the third systematic bit log-likelihood ratio.

Optionally, the HARQ feedback apparatus further includes: a second storage module, adapted to store the log-likelihood ratio of the third check bit.

Optionally, the HARQ feedback apparatus further includes: a clearing module, adapted to clear the retransmitted data and the stored content when the number of retransmissions of the retransmitted data reaches the maximum number of retransmissions.

Optionally, the HARQ feedback apparatus further includes: a third combining module, adapted to combine the symbols with subsequently received retransmission data to continue channel decoding until the maximum number of retransmissions is reached.

Optionally, if the feedback information is a negative acknowledgment, the computing module continues to receive subsequent retransmission data, otherwise, new data is received.

Compared with the prior art, the technical solutions of the embodiments of the present invention have the following beneficial effects:

The technical scheme of the present invention receives retransmission data, and calculates the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, and the retransmission data is based on the last received error The data is determined; obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio The ratio is obtained after the last received erroneous data is decoded by the channel; the first system bit log-likelihood ratio and the second system bit log-likelihood ratio are combined, and the first system bit log-likelihood ratio is combined. A parity bit log-likelihood ratio is combined with the second parity bit log-likelihood ratio. The technical scheme of the present invention compares the second system bit log-likelihood ratio and the second check bit log-likelihood ratio obtained by channel decoding the last received erroneous data, respectively, with the bit log-likelihood ratio calculated according to the retransmission data. The log-likelihood ratio of the first system bit and the log-likelihood ratio of the first check bit are combined; because the log-likelihood ratio of the second system bit after channel decoding and the log-likelihood of the second check bit Compared with the log-likelihood ratio before channel decoding, its accuracy and reliability are high, so the reliability of the log-likelihood ratio determined by the technical solution of the present invention is high; The log-likelihood ratio can improve the accuracy of subsequent symbol generation and the accuracy of system decision, thereby improving the accuracy of information transmission.

Further, the combined result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio, and the first check bit log-likelihood ratio and the second check bit log-likelihood ratio Channel decoding is performed on the combined result of the likelihood ratios to obtain a third system bit log-likelihood ratio; the second system bit log-likelihood ratio and the third system bit log-likelihood ratio are combined, to obtain the fourth systematic bit log-likelihood ratio. The technical scheme of the present invention is to combine the bit log-likelihood ratio of the third system after channel decoding of the two combining results with the bit log-likelihood ratio of the second system obtained by channel decoding the last received erroneous data , by adding a priori information, the accuracy of decoding and judging the retransmission data can be improved, thereby further improving the accuracy of information transmission.

Description of drawings

1 is a flowchart of a method for determining a log-likelihood ratio for HARQ according to an embodiment of the present invention;

2 is a flowchart of a HARQ feedback method according to an embodiment of the present invention;

3 is a schematic diagram of an application scenario of a HARQ feedback method according to an embodiment of the present invention;

4 is a schematic structural diagram of an apparatus for determining a log-likelihood ratio for HARQ according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a HARQ feedback apparatus according to an embodiment of the present invention.

Detailed ways

As described in the background art, with the development of communication technology, the existing HARQ still cannot meet the requirements in terms of information transmission accuracy.

The inventor of the present application has analyzed the prior art and found that, for a non-orthogonal multiple access system, the combining manner of the HARQ technology has a great impact on the performance of the system.

In this embodiment of the present invention, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio obtained after channel decoding the erroneous data received last time are compared with the second system bit log-likelihood ratio calculated according to the retransmission data. The log-likelihood ratio of a systematic bit and the log-likelihood ratio of the first check bit are combined; because the log-likelihood ratio of the second systematic bit after channel decoding and the log-likelihood ratio of the second check bit are Compared with the log-likelihood ratio before channel decoding, its accuracy and reliability are high, so the log-likelihood ratio determined in the embodiment of the present invention is highly reliable; The digital likelihood ratio can improve the accuracy of subsequent symbol generation and the accuracy of system decision, thereby improving the accuracy of information transmission.

On the basis of the traditional HARQ technology, the embodiment of the present invention changes its combining mechanism, improves the reliability of the log-likelihood ratio, and further improves the reliability of system information transmission.

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a flowchart of a method for determining a log-likelihood ratio for HARQ according to an embodiment of the present invention.

The log-likelihood ratio determination method for HARQ shown in FIG. 1 may include the following steps:

Step S101: Receive retransmission data, and calculate and obtain a first system bit log-likelihood ratio and a first check bit log-likelihood ratio according to the retransmission data, and the retransmission data is based on an error received last time. data determined;

Step S102: Obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, where the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are: The data of the last received error is obtained after channel decoding;

Step S103: Combine the bit log-likelihood ratio of the first system with the bit log-likelihood ratio of the second system, and combine the first check bit log-likelihood ratio with the second check bit log-likelihood ratio. The log-likelihood ratios of the test bits are combined.

In this embodiment, the method for determining the log-likelihood ratio for HARQ can be used for the receiving end.

In a specific implementation, when the decoding fails, the receiving end may request the transmitting end to retransmit the data, and the retransmitted data is determined according to the erroneous data received last time. For example, for data A1B1C1, if an error occurs in data B1 during reception, the retransmitted data can be B1; or new data can be added, and the retransmitted data can be A2B1C2.

In a specific implementation, in step S101, retransmission data may be received, and a first system bit log-likelihood ratio and a first check bit log-likelihood ratio may be obtained according to the retransmission data. Specifically, multi-user detection may be performed on the retransmitted data, and the first system bit log-likelihood ratio and the first check bit log-likelihood ratio may be obtained by calculating respectively. More specifically, the multi-user detection based on the Believable Propagation (BP) algorithm can be used, and the initial system bit log-likelihood ratio and the initial check bit log-likelihood ratio can be obtained by calculating respectively; The error (Minimum Mean Square Error, MMSE) algorithm performs multi-user detection and calculates the initial system bit log-likelihood ratio and initial parity bit log-likelihood ratio respectively.

In a specific implementation, in step S102, the log-likelihood ratio of the second system bit and the log-likelihood ratio of the second check bit may be obtained. The second systematic bit log likelihood ratio and the second check bit log likelihood ratio may be pre-stored. Specifically, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are obtained after the last received erroneous data is decoded by the channel; after obtaining the second system bit pair After the log-likelihood ratio and the log-likelihood ratio of the second check bit are obtained, they can be stored for retrieval and use in subsequent steps. For example, the second systematic bit log likelihood ratio and the second check bit log likelihood ratio may be stored in the buffer.

In a specific implementation, in step S103, the first system bit log-likelihood ratio and the second system bit log-likelihood ratio are combined, and the first check bit log-likelihood ratio is combined Combined with the log-likelihood ratio of the second check bit. Specifically, the combining results of the two combining are corresponding logarithmic inevitable ratios respectively, which can be used for subsequent steps such as channel decoding, so as to improve the feedback performance of HARQ.

In this embodiment of the present invention, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio obtained after channel decoding the erroneous data received last time are compared with the second system bit log-likelihood ratio calculated according to the retransmission data. The log-likelihood ratio of a systematic bit and the log-likelihood ratio of the first check bit are combined; because the log-likelihood ratio of the second systematic bit after channel decoding and the log-likelihood ratio of the second check bit are Compared with the log-likelihood ratio before channel decoding, its accuracy and reliability are high, so the log-likelihood ratio determined in the embodiment of the present invention is highly reliable; The digital likelihood ratio can improve the accuracy of subsequent symbol generation and the accuracy of system decision, thereby improving the accuracy of information transmission.

Preferably, the method for determining the log-likelihood ratio for HARQ shown in FIG. 1 may further include the following steps: combining the result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio , and the combined result of the log-likelihood ratio of the first check bit and the log-likelihood ratio of the second check bit is channel-decoded to obtain the log-likelihood ratio of the third system bit; The systematic bit log likelihood ratio and the third systematic bit log likelihood ratio are combined to obtain a fourth systematic bit log likelihood ratio. Specifically, the log-likelihood ratio of the fourth system bit can be used as a system decision threshold to decide whether to feed back ACK or NACK.

In the embodiment of the present invention, the bit log-likelihood ratio of the third system after channel decoding of the two combining results is combined with the bit log-likelihood ratio of the second system obtained by channel decoding the last received erroneous data. , by adding a priori information, the accuracy of decoding the retransmitted data can be improved, thereby further improving the accuracy of information transmission.

FIG. 2 is a flowchart of a HARQ feedback method according to an embodiment of the present invention.

The HARQ feedback method shown in FIG. 2 may include the following steps:

Step S201: Receive retransmission data, and calculate and obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, and the retransmission data is based on the error received last time. data determined;

Step S202: Obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, where the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are: The data of the last received error is obtained after channel decoding;

Step S203: Combine the bit log-likelihood ratio of the first system with the bit log-likelihood ratio of the second system, and combine the first check bit log-likelihood ratio with the second check bit log-likelihood ratio. The log-likelihood ratio of the test bits is combined;

Step S204: combining the result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio, and the first check bit log-likelihood ratio and the second check bit log-likelihood ratio Channel decoding is performed on the combined result of the likelihood ratios to obtain the third systematic bit log-likelihood ratio;

Step S205: using the third system bit log-likelihood ratio to generate a third check bit log-likelihood ratio;

Step S206: Generate a symbol according to the third systematic bit log likelihood ratio and the third check bit log likelihood ratio for feedback.

In this embodiment, the HARQ feedback method can be used at the receiving end.

For specific implementations of steps S201 to S203 in this embodiment, reference may be made to steps S101 to S103 shown in FIG. 1 , which will not be repeated here.

In a specific implementation, in step S204, the object of the channel decoding operation is the combined result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio, and the first check bit pair The combined result of the log-likelihood ratio and the log-likelihood ratio of the second check bit. Compared with performing channel decoding on the first system bit log-likelihood ratio and the first check bit log-likelihood ratio in the prior art, the second system bit log-likelihood ratio and the second check bit pair are added. At the same time, since the log-likelihood ratio of the second system bit and the log-likelihood ratio of the second check bit are obtained by channel decoding the erroneous data received last time, its reliability and accuracy are Therefore, the reliability and accuracy of the bit log-likelihood ratio of the third system obtained by decoding are higher.

Furthermore, in step S206, a symbol is generated according to the log-likelihood ratio of the third systematic bit and the log-likelihood ratio of the third check bit for feedback. Specifically, when the decoding of the current retransmission data fails, the receiving end generates symbol-level information and saves it; at the same time, the transmitting end is required to send subsequent retransmission data, and the receiving end will receive the subsequently retransmitted data and the current retransmission data. The generated symbol-level information is combined and then decoded. The above process can generate a certain diversity gain, reduce the number of retransmissions, and thus reduce the delay.

In this embodiment, the combining result is used to generate symbols for HARQ feedback, which can improve the accuracy of the feedback information, thereby improving the accuracy of information transmission.

Preferably, after step S206, the following step may be further included: combining the symbol with the subsequently received retransmission data to continue channel decoding until the maximum number of retransmissions is reached. It should be understood by those skilled in the art that the maximum number of retransmissions may be pre-configured or predetermined by a protocol, which is not limited in this embodiment of the present invention.

Preferably, after step S204, the following step may be further included: storing the log-likelihood ratio of the third system bit.

Preferably, after step S204, the following step may be further included: storing the log-likelihood ratio of the third check bit.

In this embodiment, by storing the bit log-likelihood ratio of the third system and the log-likelihood ratio of the third check bit, when subsequent retransmission data is received, the third system generated by the current retransmission data can be retrieved Bit log-likelihood ratio and third check bit log-likelihood ratio for merging.

Preferably, after step S204, the following step may be further included: combining the bit log-likelihood ratio of the second system and the bit log-likelihood ratio of the third system to obtain a fourth system bit log-likelihood ratio , which is used to determine feedback information. Specifically, the decoded output of the channel can be used as a system decision threshold to determine feedback information. Then, the sender can determine whether to send the retransmission data according to the feedback information. For example, if the log-likelihood ratio of the fourth systematic bit is greater than 0, an ACK is fed back; if the log-likelihood ratio of the fourth systematic bit is less than 0, a NACK is fed back. In the embodiment of the present invention, the bit log-likelihood ratio of the third system after channel decoding of the two combining results is combined with the bit log-likelihood ratio of the second system obtained by channel decoding the last received erroneous data. , by adding a priori information to the system decision threshold, the accuracy of decoding the retransmitted data can be improved, thereby improving the accuracy of information transmission.

Further, if the feedback information is a negative acknowledgement, continue to receive subsequent retransmission data, otherwise receive new data. That is to say, when the feedback information is a negative acknowledgement, it means that the current retransmission data is decoded incorrectly, and it is necessary to continue to receive subsequent retransmission data; otherwise, it means that the current retransmission data is correctly decoded, and new data can be received.

Preferably, when the number of retransmissions of the retransmitted data reaches the maximum number of retransmissions, the retransmitted data and the stored content are cleared. That is to say, each time retransmission data is received, the number of retransmissions is increased by one. When the number of retransmissions reaches the maximum number of retransmissions, it means that the receiving end decodes for many times and still has a decoding error. In order to avoid wasting resources, the retransmission data and the stored content are cleared so as to receive new data. For example, it could be to clear the contents of the cache.

FIG. 3 is a schematic diagram of an application scenario of a HARQ feedback method according to an embodiment of the present invention.

As shown in FIG. 3 , the receiving end receives the data y1 transmitted for the first time (not shown in the figure), and the detector 301 can calculate the initial system bit log-likelihood ratio and the initial check bit respectively based on the confidence propagation algorithm of multi-user detection. Log-likelihood ratio. The log-likelihood ratio of the initial systematic bits and the log-likelihood ratio of the initial check bits are input to the decoder 304 for channel decoding to obtain the log-likelihood ratio of the second systematic bits. The second systematic bit is passed through the parity bit log likelihood ratio generator 305 to generate the second parity bit log likelihood ratio. The second systematic bit log-likelihood ratio and the second check bit log-likelihood ratio are passed through the symbol generator 306 to generate symbols.

Wherein, the log-likelihood ratio of the second system bit and the log-likelihood ratio of the second check bit may be stored, for example, by using a buffer for storage.

Assuming that the first received data y1 receives an error, the receiving end receives the second transmitted data and retransmits the data y2. The retransmission data y2 is combined with the symbols generated in the first transmission and input to the detector 301 . The detector 301 may obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio by using a confidence propagation algorithm based on multi-user detection, respectively. At this time, the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio are combined by the adder 302, and the first check bit log-likelihood ratio and the The log-likelihood ratios of the second check bits are combined. The outputs of the adder 302 and the adder 303 can be input to the decoder 304 for channel decoding and output the third systematic bit log-likelihood ratio. In other words, the log-likelihood ratio of the second system bit and the log-likelihood ratio of the second check bit of the data output for the first transmission are added to the front end of the decoder 304 as prior knowledge, since the retransmission data y2 is transmitted The log-likelihood ratio of the second system bit and the log-likelihood ratio of the second check bit after channel decoding during the first transmission are combined, which increases the prior information and effectively improves the reliability of system information transmission. .

Further, the second systematic bit log-likelihood ratio of the first transmission data output and the third systematic bit log-likelihood ratio output by the retransmission data y2 are added by the adder 307 to obtain the output result, which is used as The decision threshold for decoding the retransmitted data y2. The embodiments of the present invention can better utilize the log-likelihood ratio information of each transmission data output to improve data transmission performance.

It can be understood that if the decoding of the data transmitted for the second time is incorrect, the data transmitted for the third time is retransmission data, and before the data is input to the decoder 304, the adder 302 and the adder 303 are used to convert the data into the detector. The output of 301 is combined with the third system bit log-likelihood ratio and the third check bit log-likelihood ratio after the decoding of the data channel of the second transmission. The bit log-likelihood ratio is merged; if the data of the third transmission is decoded incorrectly, the data of the fourth transmission is the retransmission data, and the merging process can refer to the processing process of the retransmission data y2; the subsequent retransmission data is based on this analogy.

If the decoding of the data transmitted for the second time is correct, the retransmission data y2 and all stored log-likelihood ratios will be cleared; new data will be received at the same time. For this process, refer to the processing process of the data y1 transmitted for the first time. To repeat.

FIG. 4 is a schematic structural diagram of an apparatus for determining a log-likelihood ratio for HARQ according to an embodiment of the present invention.

The log-likelihood ratio determining apparatus 40 for HARQ shown in FIG. 4 may include a calculating module 401 , an obtaining module 402 and a first combining module 403 .

The calculation module 401 is adapted to receive retransmission data, and calculate and obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, and the retransmission data is based on the above It is ok to receive wrong data once.

The obtaining module 402 is adapted to obtain a second system bit log-likelihood ratio and a second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio The ratio is obtained after the last received error data is decoded by the channel.

The first combining module 403 is adapted to combine the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, and combine the first check bit log-likelihood ratio with the obtained bit log-likelihood ratio. The log-likelihood ratios of the second check bits are combined.

Preferably, the log-likelihood ratio determining apparatus 40 for HARQ may further include a channel decoding module (not shown in the figure) and a second combining module (not shown in the figure). The channel decoding module is adapted to combine the result of the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, as well as the first check bit log-likelihood ratio and the second check The combined result of the bit log-likelihood ratio is channel-decoded to obtain a third system bit log-likelihood ratio; the second combining module is adapted to combine the second system bit log-likelihood ratio with the third system bit log-likelihood ratio The bit log-likelihood ratios are combined to obtain a fourth systematic bit log-likelihood ratio.

It should be noted that, in specific implementation, the first combining module 403 can be implemented by using the adder 302 and the adder 303 shown in FIG. 3; the second combining module can be implemented by using the adder 307; the first combining module 403 and The second merging module may also be implemented by using any other implementable merging device, which is not limited in this embodiment of the present invention.

For more information about the working principle and working mode of the apparatus 40 for determining the log-likelihood ratio for HARQ, reference may be made to the relevant descriptions in FIG. 1 to FIG. 3 , and details are not repeated here.

FIG. 5 is a schematic structural diagram of a HARQ feedback apparatus according to an embodiment of the present invention.

The HARQ feedback apparatus 50 shown in FIG. 5 may include a calculation module 501 , an acquisition module 502 , a first combining module 503 , a channel decoding module 504 , a check bit log-likelihood ratio generation module 505 and a symbol generation module 506 .

The calculation module 501 is adapted to receive retransmission data, and calculate and obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, and the retransmission data is based on the above It is ok to receive wrong data once.

The obtaining module 502 is adapted to obtain a second systematic bit log likelihood ratio and a second check bit log likelihood ratio, the second systematic bit log likelihood ratio and the second check bit log likelihood The ratio is obtained after the last received error data is decoded by the channel.

The first combining module 503 is adapted to combine the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, and combine the first check bit log-likelihood ratio with the The log-likelihood ratios of the second check bits are combined.

The channel decoding module 504 is adapted to combine the result of the first systematic bit log likelihood ratio and the second systematic bit log likelihood ratio, as well as the first check bit log likelihood ratio and the second check bit log likelihood ratio. Channel decoding is performed on the combined result of the bit log-likelihood ratio to obtain the third system bit log-likelihood ratio.

The check bit log-likelihood ratio generating module 505 uses the third systematic bit log-likelihood ratio to generate a third check bit log-likelihood ratio.

The symbol generation module 506 is adapted to generate symbols for feedback based on the third systematic bit log likelihood ratio and the third check bit log likelihood ratio.

For specific implementations of the calculation module 501 , the acquisition module 502 and the first combination module 503 in this embodiment, reference may be made to the foregoing description of the calculation module 401 , the acquisition module 402 and the first combination module 403 shown in FIG. Repeat.

Preferably, the HARQ feedback apparatus 50 shown in FIG. 5 may include a second combining module (not shown in the figure), and the second combining module is adapted to combine the log-likelihood ratio of the second systematic bit with the third systematic bit The log-likelihood ratios are combined to obtain a fourth systematic bit log-likelihood ratio, which is used to determine feedback information. Further, if the feedback information is a negative acknowledgement, the computing module 501 continues to receive subsequent retransmission data, otherwise, new data is received.

Preferably, the HARQ feedback apparatus 50 shown in FIG. 5 may include a first storage module (not shown in the figure), and the first storage module is adapted to store the third systematic bit log-likelihood ratio.

Preferably, the HARQ feedback apparatus 50 shown in FIG. 5 may include a second storage module (not shown in the figure), and the second storage module is adapted to store the log-likelihood ratio of the third check bit.

Preferably, the HARQ feedback apparatus 50 shown in FIG. 5 may include a clearing module (not shown). The clearing module is adapted to clear the retransmitted data and the stored content when the number of retransmissions of the retransmitted data reaches the maximum number of retransmissions.

Preferably, the HARQ feedback apparatus 50 shown in FIG. 5 may include a third combining module (not shown). The third combining module is adapted to combine the symbols with the subsequently received retransmission data to continue channel decoding until the maximum number of retransmissions is reached

For more content about the working principle and working mode of the HARQ feedback apparatus 50, reference may be made to the relevant descriptions in FIG. 1 to FIG. 4, and details are not repeated here.

Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage medium can include: ROM, RAM, magnetic disk or optical disk, etc.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be based on the scope defined by the claims.

Claims (18)

1. a method for determining a log-likelihood ratio for HARQ, comprising: Receive the retransmitted data, and calculate the first systematic bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmitted data, and the retransmitted data is determined according to the last received erroneous data ; Obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are the above It is obtained after receiving the wrong data after channel decoding; The first systematic bit log likelihood ratio and the second systematic bit log likelihood ratio are combined by an adder, and the first check bit log likelihood ratio is combined with the said first check bit log likelihood ratio by an adder. The log-likelihood ratios of the second check bits are combined. 2. log-likelihood ratio determination method according to claim 1, is characterized in that, also comprises: The combined result of the first systematic bit log likelihood ratio and the second systematic bit log likelihood ratio, and the first check bit log likelihood ratio and the second check bit log likelihood ratio The combined result is channel-decoded to obtain the third system bit log-likelihood ratio; The second systematic bit log likelihood ratio and the third systematic bit log likelihood ratio are combined to obtain a fourth systematic bit log likelihood ratio. 3. A HARQ feedback method, comprising: Receive the retransmitted data, and calculate the first systematic bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmitted data, and the retransmitted data is determined according to the last received erroneous data ; Obtain the second system bit log-likelihood ratio and the second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio are the above It is obtained after receiving the wrong data after channel decoding; The first systematic bit log likelihood ratio and the second systematic bit log likelihood ratio are combined by an adder, and the first check bit log likelihood ratio is combined with the said first check bit log likelihood ratio by an adder. The second check bit log-likelihood ratio is combined; The combined result of the first systematic bit log likelihood ratio and the second systematic bit log likelihood ratio, and the first check bit log likelihood ratio and the second check bit log likelihood ratio The combined result is channel-decoded to obtain the third system bit log-likelihood ratio; Using the third systematic bit log likelihood ratio to generate a third check bit log likelihood ratio; A symbol is generated for feedback based on the third systematic bit log likelihood ratio and the third check bit log likelihood ratio. 4. The HARQ feedback method according to claim 3, further comprising: The second systematic bit log likelihood ratio and the third systematic bit log likelihood ratio are combined to obtain a fourth systematic bit log likelihood ratio, which is used for determining feedback information. 5. The HARQ feedback method according to claim 4, wherein the combined result of the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, and the first systematic bit log-likelihood ratio After channel decoding is performed on the combined result of the log-likelihood ratio of the check bits and the log-likelihood ratio of the second check bits, the method further includes: The third systematic bit log-likelihood ratio is stored. 6. The HARQ feedback method according to claim 4, wherein the combined result of the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio, and the first systematic bit log-likelihood ratio After the combined result of the log-likelihood ratio of the check bits and the log-likelihood ratio of the second check bits is subjected to channel decoding, it further includes: The third check bit log-likelihood ratio is stored. 7. The HARQ feedback method according to claim 5 or 6, further comprising: When the number of retransmissions of the retransmitted data reaches the maximum number of retransmissions, the retransmitted data and the stored content are cleared. 8. The HARQ feedback method according to claim 6, further comprising: The symbols are combined with subsequently received retransmission data to continue channel decoding until the maximum number of retransmissions is reached. 9. The HARQ feedback method according to claim 4, further comprising: If the feedback information is a negative acknowledgement, continue to receive subsequent retransmission data, otherwise receive new data. 10. A device for determining a log-likelihood ratio for HARQ, comprising: A calculation module, adapted to receive retransmission data, and calculate and obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, the retransmission data is based on the last received data erroneous data identified; an acquisition module, adapted to acquire a second system bit log-likelihood ratio and a second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio The ratio is obtained after the last received error data is decoded by the channel; A first combining module, adapted to combine the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio by an adder, and combine the first check bit pair by an adder The log-likelihood ratio is combined with the second check bit log-likelihood ratio. 11. The log-likelihood ratio determining device according to claim 10, characterized in that, further comprising: The channel decoding module is adapted to combine the result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio, as well as the first check bit log-likelihood ratio and the second check bit log-likelihood ratio. Perform channel decoding on the combined result of the bit log-likelihood ratio to obtain the third system bit log-likelihood ratio; The second combining module is adapted to combine the bit log-likelihood ratio of the second system and the bit log-likelihood ratio of the third system to obtain a fourth system bit log-likelihood ratio. 12. A HARQ feedback device, comprising: A calculation module, adapted to receive retransmission data, and calculate and obtain the first system bit log-likelihood ratio and the first check bit log-likelihood ratio according to the retransmission data, the retransmission data is based on the last received data erroneous data identified; an acquisition module, adapted to acquire a second system bit log-likelihood ratio and a second check bit log-likelihood ratio, the second system bit log-likelihood ratio and the second check bit log-likelihood ratio The ratio is obtained after the last received error data is decoded by the channel; A first combining module, adapted to combine the first systematic bit log-likelihood ratio and the second systematic bit log-likelihood ratio by an adder, and combine the first check bit pair by an adder combining the log-likelihood ratio with the log-likelihood ratio of the second check bit; The channel decoding module is adapted to combine the result of the first system bit log-likelihood ratio and the second system bit log-likelihood ratio, as well as the first check bit log-likelihood ratio and the second check bit log-likelihood ratio. Perform channel decoding on the combined result of the bit log-likelihood ratio to obtain the third system bit log-likelihood ratio; a check bit log-likelihood ratio generating module, using the third system bit log-likelihood ratio to generate a third check bit log-likelihood ratio; A symbol generation module adapted to generate symbols for feedback according to the third systematic bit log-likelihood ratio and the third check bit log-likelihood ratio. 13. The HARQ feedback device according to claim 12, further comprising: The second combining module is adapted to combine the bit log-likelihood ratio of the second system and the bit log-likelihood ratio of the third system to obtain a fourth system bit log-likelihood ratio, which is used for determining feedback information. 14. The HARQ feedback device according to claim 13, further comprising: The first storage module is adapted to store the bit log-likelihood ratio of the third system. 15. The HARQ feedback device according to claim 13, further comprising: The second storage module is adapted to store the log-likelihood ratio of the third check bit. 16. The HARQ feedback device according to claim 14 or 15, further comprising: The clearing module is adapted to clear the retransmitted data and the stored content when the number of retransmissions of the retransmitted data reaches the maximum number of retransmissions. 17. The HARQ feedback device according to claim 15, further comprising: The third combining module is adapted to combine the symbols with the subsequently received retransmission data to continue channel decoding until the maximum number of retransmissions is reached. 18 . The HARQ feedback device according to claim 13 , wherein, if the feedback information is a negative acknowledgement, the calculation module continues to receive subsequent retransmission data, otherwise, new data is received. 19 .

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