阅读说明：本技术 一种提升DVB-RCS2中Turbo译码性能的方法及译码结构 (Method for improving Turbo decoding performance in DVB-RCS2 and decoding structure ) 是由 卜智勇 王炜 陈强 于 2021-08-11 设计创作，主要内容包括：本发明提供一种提升DVB-RCS2中Turbo译码性能的方法及译码结构,所述方法为采用双二元Turbo译码结构对待译码序列进行译码；所述双二元Turbo译码结构包括基于Max-log-MAP算法的SISO译码核一和SISO译码核二、对应SISO译码核一和SISO译码核二的加权表一和加权表二、基于DVB-RCS2标准的加扰模块一、加扰模块二、解扰模块一和解扰模块二、以及硬判决模块。本发明采用双二元Turbo译码结构对待译码序列进行译码,相较于传统直接采用Max-log-MAP算法时,译码性能能够有0.2～0.4dB的提升,因此本发明能够更好地补偿Max-Log-MAP算法由于近似损失导致的译码性能恶化。(The invention provides a method for improving Turbo decoding performance in DVB-RCS2 and a decoding structure, wherein the method is to decode a sequence to be decoded by adopting a dual-binary Turbo decoding structure; the dual-binary Turbo decoding structure comprises a first SISO decoding core and a second SISO decoding core based on a Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on a DVB-RCS2 standard and a hard decision module. According to the method, a dual-binary Turbo decoding structure is adopted to decode the sequence to be decoded, and compared with the traditional method that a Max-Log-MAP algorithm is directly adopted, the decoding performance can be improved by 0.2-0.4 dB, so that the decoding performance deterioration caused by the approximate loss of the Max-Log-MAP algorithm can be compensated better.)

1. A method for improving Turbo decoding performance in DVB-RCS2 is characterized in that the method adopts a dual-binary Turbo decoding structure to decode a sequence to be decoded; the dual-binary Turbo decoding structure comprises a first SISO decoding core and a second SISO decoding core based on a Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on a DVB-RCS2 standard and a hard decision module;

the method comprises the following steps:

step S1, when the ith iteration decoding, the system bit soft information in the sequence to be decodedAndfirst check bit soft informationAndand prior probabilityInputting the data into SISO decoding kernel I, and calculating to obtain the outer probabilityAnd posterior probability L^(z)(u_k) (ii) a The sequence to be coded is u_kZ, z ∈ {00,01,10,11} represents a bit of a sequence to be decoded;

step S2, the external probability obtained in step S1Scrambling by the scrambling module I, and outputting the scrambled outer probability output by the scrambling module IAnd the weight value output by the second weighting tableMultiplying to obtain the prior probability of SISO decoding kernel twoWherein, the weight valueThe current iteration frequency is obtained by checking a second weighting table through the waveform ID number of the RCS2 and the current iteration frequency i;

step S3, system bit soft information in the sequence to be decodedAndscrambling by a second scrambling module, and outputting the second scrambling module and second check bit soft informationAndand the prior probability obtained in step S2Inputting SISO decoding kernel two, and calculating to obtain the outer probabilityAnd posterior probability L^(z)(u_k)；

Step S4, the external probability obtained in step S3And posterior probability L^(z)(u_k) Descrambling is respectively carried out by the descrambling module I and the descrambling module II, and the descrambled external probability output by the descrambling module I is usedAnd the weight value output by the weighting tableMultiplying to obtain the prior probability of SISO decoding kernel oneWherein, the weight valueThe method is obtained by checking a first weighting table through an RCS2 waveform ID number and the current iteration times i;

step S5, repeating steps S1-S4, and executing step S6 when the iterative decoding times reach the set maximum iterative times;

step S6, the posterior probability L after descrambling by the descrambling module II in step S4^(z)(u_k) Inputting the data into a hard decision module, calculating by a hard decision algorithm, and outputting the bits of the decoding result

2. The method for improving Turbo decoding performance in DVB-RCS2 according to claim 1, wherein the SISO decoding kernel I and SISO decoding kernel II based on the Max-log-MAP algorithm have the same structure and each comprise a branch metric calculation module, a forward metric calculation module, a backward metric calculation module, a posterior probability calculation module and an outer probability calculation module.

3. The method for improving the Turbo decoding performance in DVB-RCS2 of claim 2, wherein the SISO decoding kernel-one in step S1 is calculated to obtain the outer probabilityAnd posterior probability L^(z)(u_k) The method comprises the following substeps:

in step S11, the branch metric calculation module uses the systematic bit soft informationAndfirst check bit soft informationAndand prior probabilityCalculating branch metric values for register state transitions from s' to sFormula for calculationThe following were used:

in the formula:

is a symbol of a systematic bit map of the sequence to be decoded,

is the symbol of the check bit map of the sequence to be decoded,

k denotes the sequence u to be decoded_kN denotes the sequence u to be decoded_kThe number of encoding times of (a);

step S12, the forward metric calculation module utilizes the branch metric valueCalculating a forward metric a_kThe calculation formula is as follows:

forward metric a_kInitial value of (2)Comprises the following steps:

step S13, backward measure calculating module utilizes the branch measure valueCalculating a backward measure beta_kThe calculation formula is as follows:

backward measure beta_kInitial value of (2)Comprises the following steps:

step S14, the posterior probability calculation module uses the branch metricForward metric a_kAnd a backward metric beta_kCalculating posterior probability L^(z)(u_k) The calculation formula is as follows:

in step S15, the outer probability calculation module utilizes the posterior probability L^(z)(u_k) And systematic bit soft informationAndcomputing extrinsic probabilitiesThe calculation formula is as follows:

4. the method for improving the performance of Turbo decoding in DVB-RCS2 of claim 1, wherein the step S1 is performed by using a priori probabilities during the 1 st iterative decodingThe initial value is 0.

5. The method for improving the Turbo decoding performance in DVB-RCS2 according to claim 1, wherein the hard decision algorithm in step S6 has the following formula:

in the formula (I), the compound is shown in the specification,and z represents a bit of the sequence to be decoded.

6. The method for improving the Turbo decoding performance in DVB-RCS2 of claim 1, wherein the weight tables I and II have different weights for the same RCS2 waveform ID and the same number of iterations.

7. A decoding structure for improving Turbo decoding performance in DVB-RCS2 is characterized in that the decoding structure is a dual-binary Turbo decoding structure; the dual-binary Turbo decoding structure comprises a first SISO decoding core and a second SISO decoding core based on a Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on a DVB-RCS2 standard and a hard decision module;

the output end of the SISO decoding core I is connected with the input end of the SISO decoding core II through the scrambling module and the multiplier I; the output end of the SISO decoding core II is connected with the input end of the SISO decoding core I through a descrambling module I and a multiplier II on one hand, and is connected with a hard decision module through the descrambling module II on the other hand; the input end of the SISO decoding core II is also connected with a scrambling module II; the first multiplier is also connected with a second weighting table, and the second multiplier is also connected with the first weighting table.

8. The decoding structure for improving Turbo decoding performance in DVB-RCS2 according to claim 7, wherein the SISO decoding kernel I and SISO decoding kernel II based on the Max-log-MAP algorithm have the same structure, and each of them comprises a branch metric calculating module, a forward metric calculating module, a backward metric calculating module, a posterior probability calculating module and an outer probability calculating module;

the branch metric calculation module is respectively connected with the forward metric calculation module and the posterior probability calculation module; the forward measurement computing module is respectively connected with the backward measurement computing module and the posterior probability computing module; the backward measurement calculation module is connected with the posterior probability calculation module; the posterior probability calculation module is connected with the external probability calculation module.

Technical Field

The invention relates to the technical field of communication, in particular to a method for improving Turbo decoding performance in DVB-RCS2 and a decoding structure.

Background

DVB-RCS2 is the latest ETSI standard for satellite communication, and compared with the previous generation DVB-RCS, the new standard adopts a 16-state dual binary Turbo code with better performance as its physical layer FEC code pattern. Compared with the traditional binary Turbo code, the dual binary Turbo code has the following advantages: (1) one clock completes two-bit encoding, and the encoding efficiency is higher; (2) the interleaving depth is reduced by half, and the decoding delay is smaller; (3) the error-floor is lower. Due to its excellent performance, dual binary Turbo codes have been widely used in wireless communication systems.

The classical Turbo decoding algorithm mainly comprises a Soft Output Viterbi (SOVA) algorithm and a Maximum A Posteriori (MAP) algorithm, and the latter algorithm gradually becomes an algorithm generally adopted by a Turbo decoder due to better decoding performance. However, the algorithm involves a large number of exponential operations and multiplication operations, and the hardware implementation has high complexity, which becomes an obvious short board. To reduce the complexity of the operation, the improved log-MAP algorithm converts the operation into the logarithmic domain, and converts the multiplication operation into the addition operation. The Max-Log-MAP algorithm further simplifies Log-MAP and approximately equates exponential operation to comparison selection operation. Up to now, the operation is simplified to involve only the basic add-compare-select (ACS) unit. But due to approximate loss, the decoding performance of the Max-Log-MAP algorithm is deteriorated by 0.4-0.6 dB. In order to reduce the approximate loss, J.Vogt and A.Finger propose to fix and correct the external information in the advancing the Max-Log-MAP Turbo decoder, but the J.Vogt and A.Finger can only obtain the gain of about 0.1-0.2 dB.

Disclosure of Invention

The invention aims to provide a method for improving Turbo decoding performance in DVB-RCS2 and a decoding structure, so as to better compensate decoding performance deterioration of a Max-Log-MAP algorithm caused by approximate loss.

The invention provides a method for improving Turbo decoding performance in DVB-RCS2, which is to decode a sequence to be decoded by adopting a dual-binary Turbo decoding structure; the dual-binary Turbo decoding structure comprises a first SISO decoding core and a second SISO decoding core based on a Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on a DVB-RCS2 standard and a hard decision module;

the method comprises the following steps:

step S1, when the ith iteration decoding, the system bit in the sequence to be decoded is softInformationAndfirst check bit soft informationAndand prior probabilityInputting the data into SISO decoding kernel I, and calculating to obtain the outer probabilityAnd posterior probabilityThe sequence to be coded is u_kZ, z ∈ {00,01,10,11} represents a bit of a sequence to be decoded;

step S2, the external probability obtained in step S1Scrambling by the scrambling module I, and outputting the scrambled outer probability output by the scrambling module IAnd the weight value output by the second weighting tableMultiplying to obtain the prior probability of SISO decoding kernel twoWherein, the weight valueThe current iteration frequency is obtained by checking a second weighting table through the waveform ID number of the RCS2 and the current iteration frequency i;

step S3, system bit soft information in the sequence to be decodedAndscrambling by a second scrambling module, and outputting the second scrambling module and second check bit soft informationAndand the prior probability obtained in step S2Inputting SISO decoding kernel two, and calculating to obtain the outer probabilityAnd posterior probability

Step S4, the external probability obtained in step S3And posterior probability L^(z)(u_k) Descrambling is respectively carried out by the descrambling module I and the descrambling module II, and the descrambled external probability output by the descrambling module I is usedAnd the weight value output by the weighting tableMultiplying to obtain the prior probability of SISO decoding kernel oneWherein, the weight valueThe method is obtained by checking a first weighting table through an RCS2 waveform ID number and the current iteration times i;

step S5, repeating steps S1-S4, and executing step S6 when the iterative decoding times reach the set maximum iterative times;

step S6, the posterior probability L after descrambling by the descrambling module II in step S4^(z)(u_k) Inputting the data into a hard decision module, calculating by a hard decision algorithm, and outputting the bits of the decoding result

Furthermore, the SISO decoding core I and the SISO decoding core II based on the Max-log-MAP algorithm have the same structure and respectively comprise a branch metric calculation module, a forward metric calculation module, a backward metric calculation module, a posterior probability calculation module and an external probability calculation module.

Further, in step S1, the outer probability is obtained by calculating the SISO decoding kernel oneAnd posterior probability L^(z)(u_k) The method comprises the following substeps:

in step S11, the branch metric calculation module uses the systematic bit soft informationAndfirst check bit soft informationAndandprior probabilityCalculating branch metric values for register state transitions from s' to sThe calculation formula is as follows:

in the formula:

is a symbol of a systematic bit map of the sequence to be decoded,

is the symbol of the check bit map of the sequence to be decoded,

k denotes the sequence u to be decoded_kN denotes the sequence u to be decoded_kThe number of encoding times of (a);

step S12, the forward metric calculation module utilizes the branch metric valueCalculating a forward metric a_kThe calculation formula is as follows:

forward metric a_kInitial value of (2)Comprises the following steps:

step S13, backward measure calculating module utilizes the branch measure valueCalculating a backward measure beta_kThe calculation formula is as follows:

backward measure beta_kInitial value of (2)Comprises the following steps:

step S14, the posterior probability calculation module uses the branch metricForward metric a_kAnd a backward metric beta_kCalculating posterior probability L^(z)(u_k) The calculation formula is as follows:

in step S15, the outer probability calculation module utilizes the posterior probability L^(z)(u_k) And systematic bit soft informationAndcomputing extrinsic probabilitiesThe calculation formula is as follows:

further, in step S1, the prior probability is determined in the 1 st iteration decodingThe initial value is 0.

Further, the hard decision algorithm in step S6 has the following calculation formula:

in the formula (I), the compound is shown in the specification,and z represents a bit of the sequence to be decoded.

Further, the first weighting table and the second weighting table have different weights when the waveform ID and the number of iterations of the RCS2 are the same.

The invention also provides a decoding structure for improving the Turbo decoding performance in the DVB-RCS2, wherein the decoding structure is a dual-binary Turbo decoding structure; the dual-binary Turbo decoding structure comprises a first SISO decoding core and a second SISO decoding core based on a Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on a DVB-RCS2 standard and a hard decision module;

the output end of the SISO decoding core I is connected with the input end of the SISO decoding core II through the scrambling module and the multiplier I; the output end of the SISO decoding core II is connected with the input end of the SISO decoding core I through a descrambling module I and a multiplier II on one hand, and is connected with a hard decision module through the descrambling module II on the other hand; the input end of the SISO decoding core II is also connected with a scrambling module II; the first multiplier is also connected with a second weighting table, and the second multiplier is also connected with the first weighting table.

Furthermore, the SISO decoding core I and the SISO decoding core II based on the Max-log-MAP algorithm have the same structure and respectively comprise a branch metric calculation module, a forward metric calculation module, a backward metric calculation module, a posterior probability calculation module and an external probability calculation module; the branch metric calculation module is respectively connected with the forward metric calculation module and the posterior probability calculation module; the forward measurement computing module is respectively connected with the backward measurement computing module and the posterior probability computing module; the backward measurement calculation module is connected with the posterior probability calculation module; the posterior probability calculation module is connected with the external probability calculation module.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

according to the method, a dual-binary Turbo decoding structure is adopted to decode the sequence to be decoded, and compared with the traditional method that a Max-Log-MAP algorithm is directly adopted, the decoding performance can be improved by 0.2-0.4 dB, so that the decoding performance deterioration caused by the approximate loss of the Max-Log-MAP algorithm can be compensated better.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic diagram of a method for improving Turbo decoding performance in DVB-RCS2 according to the present invention.

FIG. 2 is a schematic diagram of SISO decoding core one and SISO decoding core two based on Max-log-MAP algorithm of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The embodiment provides a method for improving Turbo decoding performance in DVB-RCS2, which is to decode a sequence to be decoded by adopting a dual-binary Turbo decoding structure; as shown in fig. 1, the dual-binary Turbo decoding structure includes a first SISO decoding core and a second SISO decoding core based on Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on DVB-RCS2 standard, and a hard decision module;

the method comprises the following steps:

step S1, when the ith iteration decoding, the system bit soft information in the sequence to be decodedAndfirst check bit soft informationAndand a prioriProbability ofInputting the data into SISO decoding kernel I, and calculating to obtain the outer probabilityAnd posterior probability L^(z)(u_k) (ii) a The sequence to be coded is u_kWhen z, z ∈ {00,01,10,11} represents the sequence u to be decoded_kAnd, at iteration 1 decoding, the prior probabilityThe initial value is 0.

As shown in FIG. 2, the SISO decoding core based on the Max-log-MAP algorithm comprises a branch metric calculation module, a forward metric calculation module, a backward metric calculation module, a posterior probability calculation module and an outer probability calculation module. Thus, the outer probability is obtained by the SISO decoding kernel one calculation in step S1And posterior probability L^(z)(u_k) The method comprises the following substeps:

in step S11, the branch metric calculation module uses the systematic bit soft informationAndfirst check bit soft informationAndand prior probabilityCalculating branch metric values for register state transitions from s' to sThe calculation formula is as follows:

in the formula:

is a symbol of a systematic bit map of the sequence to be decoded,

is the symbol of the check bit map of the sequence to be decoded,

k denotes the sequence u to be decoded_kN denotes the sequence u to be decoded_kThe number of encoding times of (a);

step S12, the forward metric calculation module utilizes the branch metric valueCalculating a forward metric a_kThe calculation formula is as follows:

forward metric a_kInitial value of (2)Comprises the following steps:

step S13, backward measure calculating module utilizes the branch measure valueCalculating a backward measure beta_kThe calculation formula is as follows:

backward measure beta_kInitial value of (2)Comprises the following steps:

it can be seen that the present invention is applied to the sequence u to be decoded with the number of encoding times N_kAnd adding and combining the (N + 1) th forward metric and the 1 st backward metric, and transmitting a combined value to the decoder for next iterative decoding to serve as an initial value of the forward metric and the backward metric during the next iterative decoding.

Step S14, the posterior probability calculation module uses the branch metricForward metric a_kAnd a backward metric beta_kCalculating posterior probability L^(z)(u_k) The calculation formula is as follows:

in step S15, the outer probability calculation module utilizes the posterior probability L^(z)(u_k) And systematic bit soft informationAndcomputing extrinsic probabilitiesThe calculation formula is as follows:

step S2, the external probability obtained in step S1Scrambling by the scrambling module I, and outputting the scrambled outer probability output by the scrambling module IAnd the weight value output by the second weighting tableMultiplying to obtain the prior probability of SISO decoding kernel twoWherein, the weight valueThe current iteration frequency is obtained by checking a second weighting table through the waveform ID number of the RCS2 and the current iteration frequency i; in other words, the weighting table is prepared according to the waveform ID number of RCS2 and the iteration number i, and is exemplified as follows: a weighting table two with the RCS2 waveform ID of 3 and the maximum number of iterations of 6 is shown in table 1.

Table 1:

scrambled outer probability of a scrambling module outputAnd the weight value output by the second weighting tableThe formula for the multiplication is as follows:

step S3, system bit soft information in the sequence to be decodedAndscrambling by a second scrambling module, and outputting the second scrambling module and second check bit soft informationAndand the prior probability obtained in step S2Inputting SISO decoding kernel two, and calculating to obtain the outer probabilityAnd posterior probability L^(z)(u_k) (ii) a The first SISO decoding core and the second SISO decoding core based on the Max-log-MAP algorithm have the same structure and respectively comprise a branch metric calculating module, a forward metric calculating module, a backward metric calculating module, a posterior probability calculating module and an outer probability calculating module, so that the specific process of the step S3 can refer to the steps S11 to S15 in the same way, and no further description is provided herein.

Step S4, the external probability obtained in step S3And posterior probability L^(z)(u_k) Descrambling is respectively carried out by the descrambling module I and the descrambling module II, and the descrambled external probability output by the descrambling module I is usedAnd the weight value output by the weighting tableMultiplying to obtain the prior probability of SISO decoding kernel oneWherein, the weight valueThe method is obtained by checking a first weighting table through an RCS2 waveform ID number and the current iteration times i; similarly to step S2, a weighting table one is also prepared according to the RCS2 waveform ID number and the iteration number i, for example: a weighting table two with the RCS2 waveform ID of 3 and the maximum number of iterations of 6 is shown in table 2.

Table 2:

as can be seen from tables 1 and 2, the weighting tables i and ii have different weights for the same RCS2 waveform ID and the same number of iterations. Descrambled external probability of one output of descrambling moduleAnd the weight value output by the weighting tableThe formula for the multiplication is as follows:

step S5, repeating steps S1-S4, and executing step S6 when the iterative decoding times reach the set maximum iterative times;

step S6, the posterior probability L after descrambling by the descrambling module II in step S4^(z)(u_k) Inputting the data into a hard decision module, calculating by a hard decision algorithm, and outputting the bits of the decoding resultThe hard decision algorithm has the following calculation formula:

in the formula (I), the compound is shown in the specification,and z represents a bit of the sequence to be decoded.

Therefore, the decoding method adopts a dual-binary Turbo decoding structure to decode the sequence to be decoded, and compared with the traditional method of directly adopting the Max-Log-MAP algorithm, the decoding performance can be improved by 0.2-0.4 dB, so that the decoding performance deterioration caused by the approximate loss of the Max-Log-MAP algorithm can be compensated better.

Example 2

Based on embodiment 1, this embodiment proposes a decoding structure for improving Turbo decoding performance in DVB-RCS2, where as shown in fig. 1, the decoding structure is a dual-binary Turbo decoding structure; the dual-binary Turbo decoding structure comprises a first SISO decoding core and a second SISO decoding core based on a Max-log-MAP algorithm, a first weighting table and a second weighting table corresponding to the first SISO decoding core and the second SISO decoding core, a first scrambling module, a second scrambling module, a first descrambling module, a second descrambling module and a second descrambling module based on a DVB-RCS2 standard and a hard decision module;

the output end of the SISO decoding core I is connected with the input end of the SISO decoding core II through the scrambling module and the multiplier I; the output end of the SISO decoding core II is connected with the input end of the SISO decoding core I through a descrambling module I and a multiplier II on one hand, and is connected with a hard decision module through the descrambling module II on the other hand; the input end of the SISO decoding core II is also connected with a scrambling module II; the first multiplier is also connected with a second weighting table, and the second multiplier is also connected with the first weighting table.

Wherein, the multiplier one is used to realize the scrambled outer probability outputted by the scrambling module one in step S2 of embodiment 1And the weight value output by the second weighting tableMultiplying to obtain the prior probability of SISO decoding kernel twoThe multiplier is used for realizing the descrambled outer probability of the step S4 of the embodiment 1 by using the output of the descrambling moduleAnd the weight value output by the weighting tableMultiplying to obtain the prior probability of SISO decoding kernel oneThe working principle of the rest of the functional modules can be executed by referring to the corresponding part in embodiment 1, and the details are not described herein.

As shown in fig. 2, the first SISO decoding core and the second SISO decoding core based on the Max-log-MAP algorithm have the same structure, and each comprise a branch metric calculating module, a forward metric calculating module, a backward metric calculating module, a posterior probability calculating module and an outer probability calculating module;

the branch metric calculation module is respectively connected with the forward metric calculation module and the posterior probability calculation module; the forward measurement computing module is respectively connected with the backward measurement computing module and the posterior probability computing module; the backward measurement calculation module is connected with the posterior probability calculation module; the posterior probability calculation module is connected with the external probability calculation module. Similarly, the working principle of the functional modules in the SISO decoding core one and the SISO decoding core two may be implemented by referring to the corresponding parts in embodiment 1, and will not be described herein again.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.