A polar code decoding method and device

Abstract

The application discloses a polar code decoding method and device. According to the position indexes of the frozen bits and the information bits corresponding to the code length and code rate of the polar code sequence, the polar code sequence to be decoded is divided into multiple special nodes such as HCF nodes, TCI nodes, Rate0 nodes, REP nodes, Rate1 nodes and SPC nodes. According to the preset multiple decoding processing modes and the corresponding relationship between the node types and the decoding processing modes, the decoding processing mode corresponding to each special node is determined, so that the most suitable decoding processing mode is adopted for each special node to reduce the decoding time delay of each special node, thereby reducing the overall decoding time delay of the decoding process. When the decoding of all special nodes is completed, the decoding result of the polar code sequence is obtained, and the technical problem of long decoding time delay of the existing polar code decoding mode is solved.

Description

Technical Field

[0001] The present application relates to the field of communications and digital circuit technology, and in particular to a polar code decoding method and device. Background Art

[0002] Polar codes are currently the only channel coding scheme proven to achieve achievable channel capacity. The core of their construction is channel polarization processing. Methods are employed on the coding side to impart different reliability levels to each subchannel. As the code length continues to increase, some channels will tend toward perfect channels (error-free) with a capacity close to 1, while others will tend toward pure noise channels with a capacity close to 0. Direct information transmission on channels with a capacity close to 1 is chosen to approach the channel capacity.

[0003] The SCL decoding algorithm is a breadth-first decoding algorithm and is currently the most widely used polar code decoding algorithm in practical engineering. This algorithm splits the path when decoding information bits, retaining multiple decoding results and introducing a path metric to evaluate the reliability of the paths in the current list. If the paths in the list are greater than a set value, the path metric is sorted and relatively reliable paths are selected for further decoding. After decoding, the most reliable path is selected as the final decoding result. If the number of paths in the list is less than the set maximum value, no sorting is performed and all decoding paths in the current list are retained for further decoding. This algorithm substantially improves decoding performance. However, as the number of lists increases, a large number of path metric calculations and path sorting are introduced, which increases latency and complexity, leading to the technical problem of high decoding latency. Summary of the Invention

[0004] The present application provides a polar code decoding method and apparatus, which are used to solve the technical problem of large delay in existing polar code decoding methods.

[0005] To solve the above technical problems, the first aspect of the present application provides a polar code decoding method, including:

[0006] Obtaining a polar code sequence to be decoded;

[0007] Divide the polar code sequence into multiple special nodes based on position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence. The special nodes include: an HCF node, a TCI node, a Rate0 node, a REP node, a Rate1 node, and an SPC node. The HCF node consists of consecutive frozen bits at the head of the polar code sequence, and the TCI node consists of consecutive information bits at the tail of the polar code sequence.

[0008] Using the LLR information input by the channel layer, the log-likelihood ratio of the current node is recursively calculated one by one;

[0009] Determine the decoding processing method corresponding to each special node based on the preset multiple decoding processing methods and the correspondence between node type and decoding processing method;

[0010] Decoding is performed on each special node according to a decoding processing mode and a log-likelihood ratio corresponding to the special node. After decoding of all special nodes is completed, a decoding result of the polar code sequence is obtained.

[0011] Preferably, dividing the polar code sequence into a plurality of special nodes according to position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence specifically includes:

[0012] traversing the bit types of the polar code sequence according to position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, and determining the first information bit and the last frozen bit in the polar code sequence;

[0013] Using the first information bit and the last frozen bit as segment identifiers, the polar code sequence is divided into a header segment, a middle segment, and a tail segment, and the header segment is used as an HCF node and the tail segment is used as a TCI node;

[0014] The middle section is divided by a binary method to obtain a Rate0 node, a REP node, a Rate1 node and an SPC node.

[0015] Preferably, according to the preset multiple decoding processing modes and the correspondence between node types and decoding processing modes, determining the decoding processing mode corresponding to each special node specifically includes:

[0016] When the special node is an HCF node, a TCI node or a Rate0 node, the decoding processing method is: decoding the special node by using a multi-bit decoding method;

[0017] When the special node is a REP node, the decoding processing method is as follows: first, splitting the path of the REP node, updating the metric value of each path according to the split path, determining the surviving path according to the metric value, and then storing the surviving path;

[0018] When the special node is an SPC node or a Rate1 node, the decoding processing method is: decoding the special node through the meiotic SCL decoding method.

[0019] Preferably, decoding the special node by using the meiotic SCL decoding method specifically includes:

[0020] determining, according to a partial order relationship of the polar codes, an unreliable information bit in the special node;

[0021] Path splitting processing is performed on the unreliable information bits, and LLR hard decision processing is performed on the remaining information bits in the special node.

[0022] Preferably, the step of recursively calculating the log-likelihood ratio of the current node one by one using the LLR information inputted by the channel layer specifically includes:

[0023] According to the division results of each special node, the starting position and the ending position of the LLR operation of each special node are determined, so as to recursively calculate the log-likelihood ratio value of each special node one by one through LLR according to the starting position and the ending position of each special node.

[0024] At the same time, the second aspect of the present application provides a polar code decoding device, including:

[0025] a polar code sequence acquisition unit, configured to acquire a polar code sequence to be decoded;

[0026] a special node division unit, configured to divide the polar code sequence into a plurality of special nodes based on position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, wherein the special nodes include: an HCF node, a TCI node, a Rate0 node, a REP node, a Rate1 node, and an SPC node; the HCF node is composed of consecutive frozen bits at the head of the polar code sequence, and the TCI node is composed of consecutive information bits at the tail of the polar code sequence;

[0027] The log-likelihood ratio calculation unit is used to recursively calculate the log-likelihood ratio value of the current node one by one using the LLR information input by the channel layer;

[0028] A decoding processing mode pairing unit is used to determine the decoding processing mode corresponding to each special node based on a plurality of preset decoding processing modes and the correspondence between node types and decoding processing modes;

[0029] The decoding result output unit is configured to perform decoding processing on each special node according to the decoding processing mode and log-likelihood ratio corresponding to the special node, and obtain a decoding result of the polar code sequence after decoding of all special nodes is completed.

[0030] Preferably, dividing the polar code sequence into a plurality of special nodes according to position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence specifically includes:

[0031] traversing the bit types of the polar code sequence according to position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, and determining the first information bit and the last frozen bit in the polar code sequence;

[0032] Using the first information bit and the last frozen bit as segment identifiers, the polar code sequence is divided into a header segment, a middle segment, and a tail segment, and the header segment is used as an HCF node and the tail segment is used as a TCI node;

[0033] The middle section is divided by a binary method to obtain a Rate0 node, a REP node, a Rate1 node and an SPC node.

[0034] Preferably, according to the preset multiple decoding processing modes and the correspondence between node types and decoding processing modes, determining the decoding processing mode corresponding to each special node specifically includes:

[0035] When the special node is an HCF node, a TCI node or a Rate0 node, the decoding processing method is: decoding the special node by using a multi-bit decoding method;

[0036] When the special node is a REP node, the decoding processing method is as follows: first, splitting the path of the REP node, updating the metric value of each path according to the split path, determining the surviving path according to the metric value, and then storing the surviving path;

[0037] When the special node is an SPC node or a Rate1 node, the decoding processing method is: decoding the special node through the meiotic SCL decoding method.

[0038] Preferably, decoding the special node by using the meiotic SCL decoding method specifically includes:

[0039] determining, according to a partial order relationship of the polar codes, an unreliable information bit in the special node;

[0040] Path splitting processing is performed on the unreliable information bits, and LLR hard decision processing is performed on the remaining information bits in the special node.

[0041] Preferably, the step of recursively calculating the log-likelihood ratio of the current node one by one using the LLR information inputted by the channel layer specifically includes:

[0042] According to the division results of each special node, the starting position and the ending position of the LLR operation of each special node are determined, so as to recursively calculate the log-likelihood ratio value of each special node one by one through LLR according to the starting position and the ending position of each special node.

[0043] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0044] The technical solution of the present application divides the polar code sequence to be decoded into multiple special nodes, such as HCF nodes, TCI nodes, Rate0 nodes, REP nodes, Rate1 nodes, and SPC nodes, based on the position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence. Then, based on multiple preset decoding processing modes and the correspondence between node type and decoding processing mode, the decoding processing mode corresponding to each special node is determined. The most appropriate decoding processing mode is then adopted for each special node for decoding, thereby reducing the decoding latency of each special node one by one, and thus reducing the decoding latency of the entire decoding process. Once all special nodes have been decoded, the decoding result of the polar code sequence is obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0046] Figure 1 This is a flowchart of an embodiment of a polar code decoding method provided by the present application.

[0047] Figure 2 This is a flowchart of step 102 of an embodiment of a polar code decoding method provided by the present application.

[0048] Figure 3 A schematic diagram of special node division in an embodiment of a polar code decoding method provided in this application.

[0049] Figure 4 This is an overall logic diagram of an embodiment of a polar code decoding method provided by this application.

[0050] Figure 5 This is a schematic structural diagram of an embodiment of a polar code decoding device provided by this application.

[0051] Figure 6 A schematic diagram of the hardware circuit for logic calculation of an embodiment of a polar code decoding device provided in this application.

[0052] Figure 7 This is a logical diagram of path metric update in an embodiment of a polar code decoding device provided by the present application.

[0053] Figure 8This is a dynamic configuration logic diagram of an embodiment of a polar code decoding device provided in this application. DETAILED DESCRIPTION

[0054] The embodiments of the present application provide a polar code decoding method and apparatus, which are used to solve the technical problem of large delay in existing polar code decoding methods.

[0055] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0056] First, a detailed description of an embodiment of a polar code decoding method provided by this application is as follows:

[0057] The explanations of the terms mentioned in this embodiment include:

[0058] Path splitting: retains all possible values ​​of the currently decoded information bit, i.e., "0" and "1". This device performs path splitting operations on the REP, SPC, and Rate1 nodes, and does not perform path splitting on other nodes;

[0059] Path metric: The estimated value is compared with the LLR hard decision value. If the two are different, a penalty value, i.e., the absolute value of the LLR, is added to the path metric value. Otherwise, the path metric value remains unchanged.

[0060] Path sorting: When the number of paths in the decoder exceeds the search width L due to path classification, the path metrics are sorted and L paths with smaller path metrics are retained for further decoding.

[0061] See also Figure 1 , an embodiment of the present application provides a polar code decoding method, including:

[0062] Step 101: Obtain a polar code sequence to be decoded;

[0063] Step 102: Divide the polar code sequence into multiple special nodes according to position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence;

[0064] It should be noted that, first, the polar code sequence to be decoded is obtained, and then the polar code sequence is divided into multiple special nodes, such as HCF node, TCI node, Rate0 node, REP node, Rate1 node, and SPC node, according to the position index of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence.

[0065] Special nodes include: HCF nodes, TCI nodes, Rate0 nodes, REP nodes, Rate1 nodes, and SPC nodes. HCF nodes consist of consecutive frozen bits at the head of the polar code sequence, and TCI nodes consist of consecutive information bits at the tail of the polar code sequence.

[0066] More specifically, if Figure 2 and Figure 3 As shown, the code point division process corresponding to step 102 in this embodiment may specifically include:

[0067] Step 1021: Based on the position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, the bit types of the polar code sequence are traversed to determine the first information bit and the last frozen bit in the polar code sequence.

[0068] Step 1022: Using the first information bit and the last frozen bit as segment identifiers, the polar code sequence is divided into a header segment, a middle segment, and a tail segment. The header segment is used as an HCF node, and the tail segment is used as a TCI node.

[0069] Step 1023: Divide the middle segment by a binary method to obtain a Rate0 node, a REP node, a Rate1 node, and an SPC node.

[0070] It should be noted that the codeword division method provided in this embodiment is different from the standard SCL decoding algorithm that estimates the source sequence bit by bit. This embodiment first divides the codeword into different special nodes according to the frozen / information bits and decodes these special nodes.

[0071] For polar codes, the partial order relationship results in a large number of consecutive frozen bits at the head of the codeword. This embodiment defines these frozen bits as a Head Consecutive Frozen (HCF) node. The tail of the codeword contains a large number of consecutive information bits, which this embodiment defines as a Tail Consecutive Information (TCI) node. The remaining middle portion is divided using a binary search method into four special nodes defined in FSC (Fast Successive Cancellation): Rate0, REP, Rate1, and SPC. The number and order of these four special nodes are not fixed and are determined by the actual polar code sequence obtained.

[0072] Step 103: Using the LLR information input by the channel layer, recursively calculate the log-likelihood ratio of the current node one by one;

[0073] It should be noted that for the logarithm likelihood ratio (LLR) calculation, the LLR information input by the channel layer is used to recursively calculate the LLR value of the intermediate layer, that is, the logarithmic likelihood ratio value. The specific calculation can refer to the LLR calculation method used in the standard SCL decoding algorithm. The difference between this embodiment and the standard SCL decoding algorithm is that it is necessary to use the special node division method mentioned above to determine the end position of the LLR operation according to the length of each divided node. The calculated LLR value can be written into the corresponding memory for storage first, so as to facilitate calling when executing the decoding process.

[0074] Step 104 determines the decoding processing method corresponding to each special node based on the preset multiple decoding processing methods and the correspondence between node type and decoding processing method;

[0075] It should be noted that, through the preset multiple decoding processing modes and the correspondence between the node type and the decoding processing mode, the decoding processing mode corresponding to each special node is determined according to the correspondence.

[0076] More specifically, if Figure 4 As shown, the meanings of the letters in the figure are: i: current decoding index; : The length of the current decoding node: The length of the current decoding node; N: The code length of the decoding codeword;

[0077] The decoding processing examples corresponding to each special node are as follows:

[0078] When the special node is an HCF node, a TCI node, or a Rate0 node, the decoding processing method is: decoding the special node through a multi-bit decoding method;

[0079] When the special node is a REP node, the decoding process is as follows: first, the path of the REP node is split, and the metric values ​​of each path are updated according to the split paths. The surviving path is determined based on the metric values, and then the surviving path is stored.

[0080] When the special node is an SPC node or a Rate 1 node, the decoding processing method is: decoding the special node through the meiotic SCL decoding method.

[0081] It should be noted that for HCF, TCI, Rate0, and REP nodes, this embodiment employs a decoding process based on multi-bit decoding. Multi-bit decoding does not require recursive LLR calculations to the decision layer. Instead, the calculation stops at a special node in the intermediate layer. The codeword bits are then determined based on the LLR sequence input to that node, thereby obtaining an estimated value for the information bit. Since Rate0 and HCF nodes do not contain information bits, they can be directly decoded as the known frozen bit "0." For REP nodes, which contain only one information bit, multi-bit decoding does not increase hardware complexity, so multi-bit decoding is performed. For the TCI node, although it contains all information bits and is the last node to be decoded, path splitting for any information bit will increase the path metric and reduce reliability. Directly performing a hard decision on the LLR sequence input to this node is the most reliable path, so this node also performs multi-bit decoding.

[0082] HCF: Since this node contains only frozen bits, it is directly decoded as an all-zero sequence. The path metric is not updated because the decoder only has one decoding path. Path metric modification simply changes the initial value of the path metric. This is the difference between HCF nodes and Rate0 nodes.

[0083] TCI: After the current node is decoded, only one optimal decoding path needs to be selected as the decoding result output. Assume that the metrics of the decoding paths in the decoder after hard decision are , then no matter which path is split, the path metric will increase, so the most reliable path must be Therefore, although this node contains all information bits, this embodiment directly hard-decides the LLR sequence input to this node to obtain an estimated value without the need for path extension. This does not result in a loss in decoding performance. This is the difference between this node and the Rate 1 node.

[0084] Rate0: This node contains frozen bits and can be directly judged as 0. The path metric is updated based on the LLR sequence input to this node. Note that this is different from the HCF node. Although both nodes contain frozen bits, since the decoder has more than one path, the inconsistency between the frozen bits and the hard decision will cause the metric of each path to change differently, affecting the final decoding result.

[0085] REP: This node contains one information bit. When decoding this node, a path extension is performed, and then the path metric and sorting are updated. The surviving path is saved and decoding is continued.

[0086] For SPC and Rate 1 nodes, since these nodes contain more information bits and the polar code partial order relationship exists, the reliability of the first two subchannels in a node is lower than that of other subchannels. Therefore, this embodiment designates the two information bits with the smallest channel sequence numbers in the current node as unreliable information bits. Multi-bit decoding is not performed on these two nodes. Instead, a standard decoding algorithm with a splitting strategy is used to perform path splitting only on unreliable information bits. The remaining information bits are directly hard-determined based on the LLRs. Specifically, path splitting is performed only on the first two information bits of Rate 1 and SPC nodes, while the remaining bits are directly hard-determined to obtain estimated values. This processing can reduce the decoding latency of SPC and Rate 1 nodes while minimizing the impact on performance.

[0087] Step 105: Decode each special node according to its corresponding decoding mode and log-likelihood ratio. After decoding of all special nodes is completed, a decoding result of the polar code sequence is obtained.

[0088] Each special node is decoded based on its corresponding decoding method and log-likelihood ratio. Due to the order of the special nodes in the polar code sequence, the decoding result of the current node is stored after the decoding result of the previous node, and is ultimately output as the decoding result.

[0089] The above is a detailed description of an embodiment of a polar code decoding method provided by the present application. The following is a detailed description of an embodiment of a polar code decoding device provided by the present application.

[0090] See also Figure 5 This embodiment provides a polar code decoding device, including:

[0091] a polar code sequence acquisition unit 201, configured to acquire a polar code sequence to be decoded;

[0092] A special node division unit 202 is configured to divide the polar code sequence into multiple special nodes based on the position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence. The special nodes include: an HCF node, a TCI node, a Rate0 node, a REP node, a Rate1 node, and an SPC node. An HCF node is composed of consecutive frozen bits at the head of the polar code sequence, and a TCI node is composed of consecutive information bits at the tail of the polar code sequence.

[0093] The log-likelihood ratio calculation unit 203 is used to recursively calculate the log-likelihood ratio value of the current node one by one using the LLR information input by the channel layer;

[0094] The decoding processing mode pairing unit 204 is configured to determine the decoding processing mode corresponding to each special node based on a plurality of preset decoding processing modes and the correspondence between node types and decoding processing modes;

[0095] The decoding result output unit 205 is configured to perform decoding processing on each special node according to the decoding processing mode and log-likelihood ratio corresponding to each special node. After decoding of all special nodes is completed, a decoding result of the polar code sequence is obtained.

[0096] Furthermore, based on the position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, the polar code sequence is divided into multiple special nodes, specifically including:

[0097] Based on the position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, the bit types of the polar code sequence are traversed to determine the first information bit and the last frozen bit in the polar code sequence;

[0098] The first information bit and the last frozen bit are used as segment identifiers to divide the polar code sequence into the head segment, the middle segment, and the tail segment. The head segment is used as the HCF node, and the tail segment is used as the TCI node.

[0099] The middle section is divided by binary division to obtain Rate0 node, REP node, Rate1 node and SPC node.

[0100] Furthermore, according to the preset multiple decoding processing modes and the correspondence between node types and decoding processing modes, determining the decoding processing mode corresponding to each special node specifically includes:

[0101] When the special node is an HCF node, a TCI node, or a Rate0 node, the decoding processing method is: decoding the special node through a multi-bit decoding method;

[0102] When the special node is a REP node, the decoding process is as follows: first, the path of the REP node is split, and the metric values ​​of each path are updated according to the split paths. The surviving path is determined based on the metric values, and then the surviving path is stored.

[0103] When the special node is an SPC node or a Rate 1 node, the decoding processing method is: decoding the special node through the meiotic SCL decoding method.

[0104] Furthermore, decoding processing of special nodes by meiotic SCL decoding method specifically includes:

[0105] Determine the unreliable information bits in special nodes based on the partial order relationship of the polar codes;

[0106] Path splitting is performed on unreliable information bits, and LLR hard decision processing is performed on the remaining information bits in special nodes.

[0107] Furthermore, using the LLR information input by the channel layer, the log-likelihood ratio value of the current node is recursively calculated one by one, specifically including:

[0108] According to the division results of each special node, the starting position and the ending position of the LLR operation of each special node are determined, so as to recursively calculate the log-likelihood ratio value of each special node one by one through LLR according to the starting position and the ending position of each special node.

[0109] In terms of the specific hardware structure, since the node length of multi-bit decoding is not fixed, the starting position of the partial sum calculation is not fixed at the decision layer, but depends on the length of the current node. A partial sum calculation architecture that can flexibly adapt to the node length is proposed, such as Figure 6 As shown, this architecture determines the starting position of the partial sum based on the length of the node, and then determines the index bit at the corresponding position. If the index bit is 0, the partial sum calculation stops, and if the index bit is 1, it continues. This partial sum calculation structure can adapt to partial sum calculations of various node lengths without increasing resources, which can improve the flexibility of the device.

[0110] like Figure 7 The figure shows the PM update module in this device that is compatible with various node lengths and can be used as an optional module. 8-bit quantization is used. Since the maximum length of the divided node is 128, the LLR of the input node is at most 1024 bits. The number of right shifts of the register is flexibly configured by the node length, and the lower eight bits of LLR and PM are added 2 v The PM value can be updated in one step. This sacrifices a small delay, greatly improves resource utilization, and is compatible with PM updates of various code lengths.

[0111] Finally, this device introduces dynamic configuration logic based on the above optimization strategy, such as Figure 8 As shown in the figure, external configuration information is fed into the dynamic configuration module, which dynamically adjusts the initial information based on different code lengths and bit rates. This information primarily includes the location of information bits and frozen bits, the number of LLR calculation layers, and node information. Based on this information, decoding can be performed for different code lengths and bit rates, making the decoder suitable for a wider range of practical application scenarios.

[0112] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the terminals, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0113] In the several embodiments provided in this application, it should be understood that the disclosed terminals, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0114] The terms "first," "second," "third," "fourth," and the like (if any) in the specification of the present application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein, for example, can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus.

[0115] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0116] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0117] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0118] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0119] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A polar code decoding method, characterized in that: include: Obtaining a polar code sequence to be decoded; Divide the polar code sequence into multiple special nodes based on position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence. The special nodes include: an HCF node, a TCI node, a Rate0 node, a REP node, a Rate1 node, and an SPC node. The HCF node consists of consecutive frozen bits at the head of the polar code sequence, and the TCI node consists of consecutive information bits at the tail of the polar code sequence. Using the LLR information input by the channel layer, the log-likelihood ratio of the current node is recursively calculated one by one; When the special node is an HCF node, a TCI node or a Rate0 node, the decoding processing method is: decoding the special node by using a multi-bit decoding method; When the special node is a REP node, the decoding processing method is as follows: first, splitting the path of the REP node, updating the metric value of each path according to the split path, determining the surviving path according to the metric value, and then storing the surviving path; When the special node is an SPC node or a Rate 1 node, the decoding processing method is as follows: determining unreliable information bits in the special node according to the partial order relationship of the polar codes, performing path splitting processing on the unreliable information bits, and performing LLR hard decision processing on the remaining information bits in the special node; Decoding is performed on each special node according to a decoding processing mode and a log-likelihood ratio corresponding to the special node. After decoding of all special nodes is completed, a decoding result of the polar code sequence is obtained.

2. The polar code decoding method according to claim 1, wherein: Dividing the polar code sequence into a plurality of special nodes according to position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence specifically includes: traversing the bit types of the polar code sequence according to position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, and determining the first information bit and the last frozen bit in the polar code sequence; Using the first information bit and the last frozen bit as segment identifiers, the polar code sequence is divided into a header segment, a middle segment, and a tail segment, and the header segment is used as an HCF node and the tail segment is used as a TCI node; The middle section is divided by a binary method to obtain a Rate0 node, a REP node, a Rate1 node and an SPC node.

3. The polar code decoding method according to claim 1, wherein: The method of recursively calculating the log-likelihood ratio of the current node one by one using the LLR information inputted by the channel layer specifically includes: According to the division results of each special node, the starting position and the ending position of the LLR operation of each special node are determined, so as to recursively calculate the log-likelihood ratio value of each special node one by one through LLR according to the starting position and the ending position of each special node.

4. A polar code decoding device, characterized in that: include: a polar code sequence acquisition unit, configured to acquire a polar code sequence to be decoded; a special node division unit, configured to divide the polar code sequence into a plurality of special nodes based on position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, wherein the special nodes include: an HCF node, a TCI node, a Rate0 node, a REP node, a Rate1 node, and an SPC node; the HCF node is composed of consecutive frozen bits at the head of the polar code sequence, and the TCI node is composed of consecutive information bits at the tail of the polar code sequence; The log-likelihood ratio calculation unit is used to recursively calculate the log-likelihood ratio value of the current node one by one using the LLR information input by the channel layer; a decoding processing mode pairing unit, configured to: when the special node is an HCF node, a TCI node, or a Rate 0 node, perform decoding processing on the special node using a multi-bit decoding mode; when the special node is a REP node, perform path splitting on the REP node, update the metrics of each path based on the split paths, determine a surviving path based on the metrics, and then store the surviving path; and when the special node is an SPC node or a Rate 1 node, perform decoding processing on unreliable information bits in the special node based on a partial order relationship of polar codes, perform path splitting on the unreliable information bits, and perform LLR hard decision processing on the remaining information bits in the special node; The decoding result output unit is configured to perform decoding processing on each special node according to the decoding processing mode and log-likelihood ratio corresponding to the special node, and obtain a decoding result of the polar code sequence after decoding of all special nodes is completed.

5. The polar code decoding device according to claim 4, wherein: Dividing the polar code sequence into a plurality of special nodes according to position indexes of frozen bits and information bits corresponding to the code length and code rate of the polar code sequence specifically includes: traversing the bit types of the polar code sequence according to position indexes of the frozen bits and information bits corresponding to the code length and code rate of the polar code sequence, and determining the first information bit and the last frozen bit in the polar code sequence; Using the first information bit and the last frozen bit as segment identifiers, the polar code sequence is divided into a header segment, a middle segment, and a tail segment, and the header segment is used as an HCF node and the tail segment is used as a TCI node; The middle section is divided by a binary method to obtain a Rate0 node, a REP node, a Rate1 node and an SPC node.

6. The polar code decoding device according to claim 4, wherein: The method of recursively calculating the log-likelihood ratio of the current node one by one using the LLR information inputted by the channel layer specifically includes: According to the division results of each special node, the starting position and the ending position of the LLR operation of each special node are determined, so as to recursively calculate the log-likelihood ratio value of each special node one by one through LLR according to the starting position and the ending position of each special node.

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