IDMA communication method and system based on extensible polarization code

Abstract

The invention provides an IDMA communication method and system based on an extensible polarization code, and relates to the technical field of wireless mobile communication, and the method comprises the steps: carrying out the extension coding operation on message bit strings, creating an information bit index set according to the extension bit strings, endowing the bit value of each message bit string to the extension bit strings according to the information bit index set, and carrying out the extension coding operation on the message bit strings; encoding the assigned extended bit string to obtain an extended code word; circulating the extended coding operation for a preset number of times to obtain a complete code word formed by connecting a plurality of extended code words; each complete code word is interleaved to obtain a plurality of interleaved sequences, and each interleaved sequence is modulated to obtain a plurality of modulation signals for communication. According to the invention, the cyclic coding operation is carried out on the message bits of multiple users, so that the improved I DMA system can meet the information transmission requirement of keeping high reliability under different user load and channel conditions, especially the transmission requirement in a short code length scene.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless mobile communications, and in particular to a communication method and system based on IDMA of scalable polar codes. Background Art

[0002] With the rapid development of the Internet of Things (IoT) and smart devices, modern wireless communication systems need to support the simultaneous access of large-scale devices, which poses severe challenges to spectrum resources and communication capacity. Interleaved Division Multiple Access (IDMA), as an effective non-orthogonal multiple access technology, enables simultaneous communication of multiple users by assigning a unique interleaver to each user. IDMA has low-complexity multi-user detection capabilities, can effectively reduce interference between users, and significantly improve spectrum utilization. Therefore, IDMA is very suitable for scenarios with large-scale device access, such as smart grids, smart homes, industrial Internet of Things, and other large-scale device real-time communication scenarios.

[0003] In practical applications, IDMA has demonstrated its advantages in supporting high-speed, low-latency concurrent communications in the fields of intelligent transportation systems, vehicle-to-everything (V2X), unmanned driving, and wireless monitoring.

[0004] Existing IDMA system coding schemes are mainly optimized for long code scenarios, such as the cascade of LDPC codes and repetition codes, which usually focus on performance close to capacity and are designed for fixed user loads or unchanged channel conditions. However, when user loads and channel conditions change, these schemes are difficult to adjust according to actual conditions. When the load changes, the performance of the communication system is unstable and cannot effectively cope with communications under different user loads; especially in the short code length scenario, when the user load increases, the system's error correction performance decreases, which in turn leads to an increase in the bit error rate. Summary of the invention

[0005] The object of the present invention is to provide a communication method and device based on IDMA of scalable polar codes to improve the above problems. In order to achieve the above objects, the technical solutions adopted by the present invention are as follows:

[0006] In a first aspect, the present application provides a communication method based on IDMA of scalable polar codes, comprising:

[0007] Acquire message bit strings of multiple users, where one message bit string is composed of multiple message bits input by one user;

[0008] performing an extended coding operation on the message bit string, wherein an information bit index set is created according to the extended bit string, a bit value of each of the message bit strings is assigned to the extended bit string according to the information bit index set, and the assigned extended bit string is encoded by a preset polar code encoder to obtain an extended codeword, wherein the extended bit string is a bit string with an initial value of 0;

[0009] The extended coding operation is cycled, and the obtained multiple extended code words are sequentially connected in the order of generation until a preset number of times is reached to obtain a complete code word;

[0010] Each of the complete codewords is interleaved by an interleaver corresponding to the user to obtain a plurality of interleaved sequences, and each of the interleaved sequences is modulated by a mapper to obtain a plurality of modulated signals for communication.

[0011] In a second aspect, the present application also provides a communication system based on IDMA of scalable polar codes, including:

[0012] An acquisition module, used for acquiring message bit strings of multiple users, wherein one message bit string is composed of multiple message bits input by one user;

[0013] a first processing module, configured to perform an extended coding operation on the message bit string, wherein an information bit index set is created according to the extended bit string, a bit value of each of the message bit strings is assigned to the extended bit string according to the information bit index set, and the assigned extended bit string is encoded by a preset polar code encoder to obtain an extended codeword, wherein the extended bit string is a bit string with an initial value of 0;

[0014] A second processing module is used to sequentially connect the obtained multiple extended code words in the order of generation until a preset number of times is reached to obtain a complete code word;

[0015] The third processing module is used to perform interleaving processing on each of the complete codewords through an interleaver corresponding to the user to obtain multiple interleaving sequences, and each of the interleaving sequences is modulated by a mapper to obtain multiple modulated signals for communication.

[0016] In a third aspect, an embodiment of the present application provides a communication device based on IDMA of scalable polar codes, the device comprising a memory and a processor. The memory is used to store a computer program; the processor is used to implement the steps of the communication method based on IDMA of scalable polar codes when executing the computer program.

[0017] In a fourth aspect, the present application also provides a readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned communication method based on IDMA based on scalable polar code are implemented.

[0018] The beneficial effects of the present invention are:

[0019] The present invention performs cyclic coding operations on message bits of multiple users, so that the improved IDMA system can meet the information transmission requirements of maintaining high reliability under different user loads and channel conditions, especially the transmission requirements in the short code length scenario.

[0020] Other features and advantages of the present invention will be set forth in the following description, and in part will become apparent from the description, or may be understood by practicing embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 It is a flow chart of a communication method based on IDMA of scalable polar code described in an embodiment of the present invention;

[0023] Figure 2 A logical schematic diagram of a communication method based on IDMA of scalable polar codes according to an embodiment of the present invention;

[0024] Figure 3 Schematic diagram of the structure of a communication system based on IDMA with scalable polar codes according to an embodiment of the present invention;

[0025] Figure 4 is a BLER performance comparison curve diagram when the number of users is 15 according to an embodiment of the present invention;

[0026] Figure 5 is the E when the number of users is 30 in the embodiment of the present invention. b / N0 performance comparison curve;

[0027] Figure 6 is a BLER performance comparison curve when the number of users is 8 according to an embodiment of the present invention;

[0028] Figure 7 is E under different equivalent repetition factors described in the embodiments of the present invention b / N0 performance comparison curve.

[0029] Markings in the figure: 901, acquisition module; 902, first processing module; 903, second processing module; 904, third processing module; 9041, first processing unit; 9042, second processing unit; 90421, first processing sub-unit; 90422, second processing sub-unit; 90423, third processing sub-unit; 9021, third processing unit; 9022, fourth processing unit; 9023, fifth processing unit; 9024, sixth processing unit; 905, fourth processing module; 906, fifth processing module; 9051, seventh processing unit. DETAILED DESCRIPTION

[0030] In order to make the purpose, 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 in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0032] Embodiment 1:

[0033] This embodiment provides a communication method based on scalable polarization code IDMA, which is used to support K users to communicate simultaneously and share the same radio resources. The encoding process of the transmitter and the decoding process of the receiver are based on a unified polarization coding configuration, and the configuration between multiple users is also consistent; at the same time, the key parameters of polarization coding, including the structure of the polarization generation matrix and the information bit index set, are also consistent among all users.

[0034] See also Figure 1 , the figure shows that the method includes step S1, step S2, step S3 and step S4.

[0035] Step S1, obtaining message bit strings of multiple users, wherein one message bit string is composed of multiple message bits input by one user;

[0036] In step S1, the number of initial message bits B is set to 5, that is, the length of each message bit string is 5; the message bit string m of user k is obtained. k , 1≤k≤K, k is an integer, and K is the number of users.

[0037] Step S2: performing an extended coding operation on the message bit string, wherein an information bit index set is created according to the extended bit string, a bit value of each message bit string is assigned to the extended bit string according to the information bit index set, and the assigned extended bit string is encoded by a preset polar code encoder to obtain an extended codeword, wherein the extended bit string is a bit string with an initial value of 0;

[0038] In step S2, the initial extension code length is set to L1 = 8, that is, when the extension number t = 1, the extension bit string is created

[0039] S21, when the extension number t=1, it is necessary to assign a value to the extended bit string according to the finally determined information bit index set, so as to perform extended polar code encoding according to the extended bit string to obtain an extended codeword at t=1;

[0040] Specifically, a first information bit index set is created, and a channel noise variance set D = {σ1,σ2,…,σ| D |}, use the Gaussian estimation algorithm to calculate the corresponding channel noise variance σ i The reliability of each subchannel under 1≤i≤N1, N1 is the mother code length corresponding to the initial polar code length L1, and the calculation formula is: Considering the influence of the QUP puncturing algorithm, some sub-channels with the lowest corresponding reliability in the first information bit index set are screened out. L1+1≤i≤N1, so that the second information bit index set A to be formed i The index range of is always from 1 to L1; then, according to the estimated subchannel reliability, all subchannels are sorted from low to high in terms of reliability, and the first B subchannels with the highest reliability are selected as the subchannels for message bit transmission, forming the channel noise variance σ i The corresponding second information bit index set is information bit index set A i , the remaining sub-channels are transmitted as frozen bits;

[0041] Furthermore, the channel noise variance σ that can minimize the BLER is selected from all candidate channel noise variance sets D. opt As the optimal parameter selection, the calculation formula is:

[0042]

[0043] The channel noise variance σ of the minimum BLER opt The corresponding second information bit index set A opt is confirmed as the optimal information bit index set, so the information bit index set A1 at t=1 is finally determined as the optimal second information bit index set A opt , whose corresponding subchannel reliability set It was finally determined to be The calculation formula is:

[0044]

[0045] The subchannel reliability of the information bit is set Arrange them in order from low to high, and adjust the order of the information bit index set A1 accordingly. The sorted information bit index set A1 will be stored in the new set In, get The main purpose of this sorting operation is to prepare for the generation of subsequent bit protection pairs. The information bits with medium and low reliability are paired with the input bits with medium and high reliability in the extension part to ensure The least reliable sub-channel in the extended part can be protected by the more reliable sub-channel in the extended part, thereby improving the error correction capability of the system.

[0046] S22, when the information bit index set A1 at t=1 is determined, the message bit string m composed of the message bits of user k k Fill in the corresponding extended bit string in sequence according to the information bit index set A1, that is, satisfy the condition For the remaining unassigned bit positions of the extended bit string Then fill it with 0, that is Get the input bit string generated by t=1

[0047] S23, construct the initial extended generator matrix First, according to the extended codeword length L t , calculate the mother code length N t , whose formula is In the first expansion, t = 1. This formula can ensure that the size of the generator matrix is ​​a power of 2, which is convenient for the recursive construction of the subsequent polar code. Then, from the generated matrix The required matrix part is intercepted from row 1 to L1 and column 1 to L1 to form the generator matrix of the extended codeword Will The input generator matrix is The polar code encoder is used to obtain the encoded polar code word That is, the first extended codeword is obtained.

[0048] S3, looping the extended coding operation, sequentially connecting the obtained multiple extended code words in the order of generation until a preset number of times is reached to obtain a complete code word, and the specific steps of S3 include:

[0049] S31, constructing a bit protection pair based on the information bit index set, and assigning a value to the extended bit string through the bit protection pair, including:

[0050] taking out an index from the information bit index sets obtained in the previous and current extended polar code encoding one by one, to obtain at least two bit protection pairs, each of the bit pairs including a low reliability element and a high reliability element, the low reliability element being an element having the lowest reliability of a corresponding subchannel in all the information bit index sets generated in the previous extended coding operation, and the high reliability index being an element having the highest reliability of a corresponding subchannel in the information bit index sets obtained in the current extended coding operation;

[0051] The bit value of the bit corresponding to the low reliability element in each of the bit protection pairs is assigned to the bit corresponding to the high reliability index.

[0052] S32, obtaining at least two bit protection pairs includes:

[0053] After each bit protection pair is constructed, the block error rate is calculated. If the corresponding block error rate does not decrease when the current bit protection pair is constructed, the latest constructed bit protection pair is discarded and the construction of the bit protection pair is stopped.

[0054] Specifically, when the number of extensions t>1, the length of each extension code is set to ΔL=6, the length of the extended bit string is ΔL=6, and the t-times extended bit string created is The length is ΔL; create a set P of bit protection pairs extended t times t , set the optimal number of bit protection pairs ΔP t ;

[0055] According to the method described in S21, find the information bit index set A expanded t times t ={L t ,L t -1,…,L t-1 +1}, the reliability of each subchannel is stored in the set In Sort by reliability from high to low (i.e., in descending order), and the corresponding subchannel index set A t It will also be rearranged according to this sorting and get a new index set

[0056] The bit protection pair formation process is optimized by calculating and comparing the bit error rate (BLER). The initial set of bit protection pairs for the first t expansions is initialized as Through simulation calculation, each additional candidate protection pair The corresponding block error rate BLER i , the calculation formula is:

[0057]

[0058] In each iteration, if the current protection pair Can reduce the system's block error rate (BLER i ≤BLER i-1 ), then the bit protection pair Will be added to the current bit protection pair set P t In, it is expressed as: At the same time, the information bit set A1 and the channel reliability set The following update will also be performed according to formula (4):

[0059]

[0060] During the expansion process, the subchannels with lower reliability in the information bit index set A1 will be expanded. t The higher reliability of the subchannel is replaced in order to optimize the system performance. i Greater than the previous BLER i-1 , terminate the process of building protection pairs, because further generation of bit protection pairs will not bring performance improvement. Finally, the optimal number of bit protection pairs ΔP is determined t ←|P t | and bit protection pair set P t .

[0061] Furthermore, when the channel quality deteriorates, the codeword needs to be extended once more. When t = 2, the codeword length is extended to L2 = L1 + ΔL = 14. The system can cope with the change of channel conditions without reconstructing the polarization code. This extension involves padding 6 additional codewords into the transmission sequence, while the initial information bit index set A1 remains unchanged. As of the last extension, all used protection pairs are set Under the same parameters, determine the optimal bit protection pair set P2 under this channel condition. According to the following steps, gradually confirm the extended codeword with the extension number t=2

[0062] S33, according to the bit protection pair set P t, the value of the input bit at position 2j in the set Copy the input bit to position 2j-1 Right now Among them, P t The input bit at position (2j-1) has been determined in the previous 1 to t-1 extensions. t (2j-1) represents the index of the newly added information bit, and P t (2j) is the protected bit index.

[0063] Specifically, when t = 2, the GA algorithm is first used to calculate the reliability of the subchannels in the extended part. The subchannel index set of the extended part is A2 = {14, 13, ..., 9}, and the reliability of each subchannel is stored in the set Next, The reliability is sorted from high to low (i.e., in descending order), and the corresponding subchannel index set A2 is also rearranged according to this sorting to obtain a new index set After the above iteration process, two bit protection pairs are finally selected: {9,4} and {13,5}. It is worth noting that when the third bit protection pair is generated, since the BLER cannot be further reduced at this time, the generation of more protection pairs is stopped. The information bit index set A1 is finally updated to A1 = {9,13,3,2,1}, and the channel reliability set Updated as well.

[0064] S34, the current extension input bit string With all previous expansions of the input bit string Concatenate to form a new polar code input bit string And generate according to step S23 The corresponding generator matrix Get the extended codeword of the t-time polarization code extension In this way, the entire step ensures that the polar code after each expansion can adapt to the user load and channel conditions of the current system, ensuring the correct generation and transmission of the codeword.

[0065] Specifically, when t = 2, the message bit u 4,k and u 5,k are copied to u separately 9,k and u 13,5 , and set the other extended input bits to 0. The extended input bit string is defined as This shows that the extended codeword can continue to maintain a high error correction capability under harsh channel conditions by matching these high and low reliability bit pairs in the polar code. Then construct the extended generator matrix G 14:1,14:9 ; Then connect this and all previous extended input bit strings together to form a new polar code input bit string Will The input generator matrix is ​​G 14:1,14:9 The polar code encoder is used to obtain the encoded polar code word That is, the extended code word of the t=2th time is obtained.

[0066] The introduction of the bit protection pair mechanism further enhances the error correction capability of the system. By pairing high-reliability sub-channels with low-reliability sub-channels, this mechanism effectively improves the system's error-resistance capability under harsh channel conditions. The bit protection pair mechanism enables the system to dynamically adjust the reliability of different information bits in the channel, thereby improving the overall error correction performance and significantly improving the reliability and performance of transmission. This optimized design is particularly suitable for multi-user dynamic load scenarios and transmission requirements under complex channel conditions.

[0067] S4, each of the complete codewords is interleaved by the interleaver corresponding to the user to obtain multiple interleaved sequences, and each of the interleaved sequences is modulated by the mapper to obtain multiple modulated signals for communication.

[0068] Specifically, in S4, the user-specific interleaver is used to ensure that the signals between users do not interfere with each other during transmission. After T times of expansion, all the expanded codewords will be connected to form a complete codeword c k = After passing through the user-specific interleaver, the interleaved sequence w is obtained k =π k (c k ). The interleaved data is modulated by a mapper using binary phase shift keying (BPSK). The symbol sequence after modulation is where {φ k} is the introduced random phase scrambler, which is uniformly distributed in the interval [0,π. The main purpose of introducing random phase scrambling is to reduce the interference between symbols in multi-user scenarios, especially in high-speed mobile communication environments. After random phase scrambling, the signal is transmitted through a block fading channel. The signal received by the receiver is a signal superimposed by multiple users, which is expressed as:

[0069]

[0070] Among them, x k,i represents the modulation symbol sent by the kth user in the i-th time slot, h k,i is the channel coefficient, P k is the transmission power of the kth user, z i ~CN(0,σ 2 ) is additive white Gaussian noise (AWGN). If the channel is a Rayleigh fading channel, the phase scrambling code φ k You can choose whether to introduce it according to specific needs.

[0071] according to Figure 2 As shown, this embodiment also includes processing steps at the receiving end, as follows:

[0072] At the receiving end, the received signal y is passed through the on-chip soft interference cancellation multi-user detector (SoIC-MUD) to estimate the multi-user interference. In this process, each user's signal treats the signals of the other K-1 users as Gaussian interference and makes a preliminary estimate. This process effectively eliminates the interference from other users, allowing the target user's signal to be recovered more accurately. The interference-cancelled signal then enters the demapping and descrambling module to calculate the log-likelihood ratio (LLR) value for each bit. During this process, user-specific phase scrambling techniques further remove residual symbol interference, which is critical for improving signal clarity, especially in high-interference environments. The signal then passes through the deinterleaving module to restore the symbol order before encoding. This operation restores each user's signal from the interleaved state back to the original order so that the subsequent decoding process can proceed smoothly. Next, the belief propagation (BP) decoder of the polar code runs several iterations to further optimize the symbol estimate. The iterations of the BP decoder repeatedly update the symbols based on the received LLR values, gradually improving the decoding accuracy with each iteration.

[0073] The whole process will be repeated in multiple iterations until all users' symbols are fully recovered or the preset maximum number of iterations is reached. It is worth noting that in the case of a bit protection pair mechanism, the uniqueness of BP decoding is that the framework at the receiving end treats each bit protection pair as a variable node. Each bit protection pair is introduced as a node, which can dynamically update information during the BP decoding process. This mechanism greatly enhances the system's anti-interference and error correction capabilities under complex channel conditions, ensuring high-reliability transmission.

[0074] Specifically, the BP decoder runs multiple iterations, and during each iteration, the system dynamically updates the variable nodes introduced by each bit protection pair. For the bit protection pairs in the current extended codeword, such as {9,4} and {13,5}, these nodes are considered as particularly important variable nodes, and the information is dynamically updated during the BP iteration.

[0075] The iterative process of the BP decoder will terminate when the following conditions are met:

[0076] 1. All users’ information sequences are recovered: When all users’ symbols are successfully recovered, the decoder stops iterating.

[0077] 2. Reaching the preset number of iterations: If the symbols of all users cannot be fully restored within the specified maximum number of iterations, the iteration process will end early.

[0078] Through this process, the symbol information of each user will be restored, and due to the introduction of the bit protection mechanism, the system can still maintain a high error correction performance under harsh channel conditions, ensuring high-reliability transmission in multi-user scenarios.

[0079] The present invention verifies its effectiveness in multi-user dynamic load scenarios by conducting simulation experiments under different channel conditions. The specific experimental settings are as follows: the experiments are conducted in AWGN channels and quasi-static 16-path Rayleigh fading channels, using QPSK modulation, and the number of users is set to 8, 15, and 30, respectively. The polar code lengths used are 128, 256, and 1024, respectively, and the number of channel paths set under the Rayleigh channel is 16. The total transmission rate of the system is set to 0.5 bits per channel (bpcu) and 1bpcu, respectively. The experiment compares the block error rate (BLER) performance of the scheme of the present invention with that of the Polar-Rep-IDMA scheme, and examines the performance of the two schemes in different channel conditions under different equivalent repetition factors, thereby verifying the reliability and performance advantages of the present invention under AWGN and Rayleigh channels.

[0080] like Figure 4 As shown, under AWGN channel conditions, the simulation conditions are total code length of 4096, number of users of 15, and total rate of 0.5bpcu. The simulation results show that when BLER is achieved, the present invention achieves a performance gain of 0.5dB compared with the prior art Polar-Rep-IDMA scheme, which fully proves the bit error rate advantage of the present invention in a low signal-to-noise ratio environment. The present invention can effectively reduce the bit error rate under AWGN channels and improve the transmission reliability of the system, and is particularly suitable for communication scenarios with dynamic changes in multi-user loads and harsh channel conditions.

[0081] like Figure 5As shown, when the number of users is K = 30 and the total rates are R sum =1bpcu and R sum = 0.5 bpcu, message size B = 64, equivalent repetition factor d r is E under different values ​​and AWGN channel conditions b / N0 performance comparison curve. The horizontal axis in the figure is the equivalent repetition factor d r , the vertical axis is E b / N0 value (unit: dB).

[0082] from Figure 5 It can be seen that the Polar-Rep-IDMA scheme can achieve the best performance under certain specific repetition factors, significantly reducing the required minimum E b / N0 value. However, the scheme proposed in the present invention shows relatively stable performance under the influence of the equivalent repetition factor, and its performance is always better than the baseline Polar-Rep-IDMA scheme in the entire repetition factor range. This shows that the present invention can maintain higher communication quality under variable channel conditions and different user loads, and show more stable performance advantages under low signal-to-noise ratio conditions.

[0083] Figure 6 The BLER performance comparison curve of the method of the present invention under the conditions of K=8 users, QPSK modulation, and quasi-static 16-path Rayleigh fading channel. b / N0 value (unit: dB), the ordinate is BLER. The mark "+" in the figure represents the Polar-REP-IDMA scheme, the mark "▽" represents the SDD SCL scheme, the mark "○" represents the SDD BP scheme, the mark "★" represents the scheme of the present invention, the mark "--" is the single-user performance curve, and the mark "-." represents the Shannon limit.

[0084] from Figure 6 It can be seen that the solution proposed by the present invention is b / N0 range, it is better than Polar-REP-IDMA, SDD SCL and SDD BP solutions. Especially when the BLER is 10 -3 When compared with the Polar-REP-IDMA scheme, the scheme of the present invention achieves a performance gain of about 1 dB, indicating that the present invention can provide better error resistance performance and communication reliability under harsh channel conditions.

[0085] Figure 7 The method of the present invention is used in a quasi-static 16-path Rayleigh fading channel, with the number of users being K=30 and the total rates being R sum =1bpcu and R sum= 0.5 bpcu, message size B = 64, equivalent repetition factor d r is E under different values b / N0 performance comparison curve. The horizontal axis in the figure is the equivalent repetition factor d r , the vertical axis is E b / N0 value (unit: dB).

[0086] from Figure 7 It can be seen that the Polar-Rep-IDMA scheme has a certain repetition factor d r The best performance can be achieved under the condition of significantly reducing the minimum required E b / N0 value. However, the PME-Polar-IDMA scheme proposed in the present invention shows relatively stable performance under the influence of the equivalent repetition factor, and its performance is always better than the baseline Polar-Rep-IDMA scheme in the entire repetition factor range. This shows that the present invention can maintain higher communication quality under the condition of quasi-static 16-path Rayleigh fading channel, and show more stable performance advantages under low signal-to-noise ratio conditions.

[0087] Embodiment 2:

[0088] like Figure 3 As shown, this embodiment provides a communication system based on IDMA of scalable polar codes, the system comprising an acquisition module 901, a first processing module 902, a second processing module 903 and a third processing module 904, wherein specifically:

[0089] An acquisition module 901 is used to acquire message bit strings of multiple users, where one message bit string is composed of multiple message bits input by one user;

[0090] A first processing module 902 is configured to perform an extended coding operation on the message bit string, wherein an information bit index set is created according to the extended bit string, a bit value of each message bit string is assigned to the extended bit string according to the information bit index set, and the assigned extended bit string is encoded by a preset polar code encoder to obtain an extended codeword, wherein the extended bit string is a bit string with an initial value of 0;

[0091] The second processing module 903 is used to sequentially connect the obtained multiple extended code words in the order of generation until a preset number of times is reached to obtain a complete code word;

[0092] The third processing module 904 is used to perform interleaving processing on each of the complete codewords through an interleaver corresponding to the user to obtain multiple interleaved sequences. Each of the interleaved sequences is then modulated by a mapper to obtain multiple modulated signals for communication.

[0093] The third processing module 904 includes a first processing unit 9041 and a second processing unit 9042:

[0094] The first processing unit 9041 is used to sequentially connect the extended bit string after the value is assigned in the current extended coding operation with the extended bit string after the value is assigned obtained in the previous extended coding operation in a generation order to obtain an input bit string for the current extended coding operation;

[0095] The second processing unit 9042 encodes the input bit string through a preset polar code encoder to obtain the extended codeword.

[0096] The second processing unit 9042 includes a first processing subunit 90421, a second processing subunit 90422 and a third processing subunit 90423:

[0097] The first processing subunit 90421 is used to calculate the mother code length according to the length of the input bit string, and construct a mother code generation matrix corresponding to the mother code length; the scale of the mother code generation matrix is ​​a power of 2;

[0098] A second processing subunit 90422 is configured to intercept a part of the mother code generation matrix based on the information bit index set and the length of the extended bit string to obtain an extended generation matrix;

[0099] The third processing subunit 90423 is configured to input the input bit string into a polar code encoder corresponding to the extended generation matrix to obtain the extended codeword.

[0100] The first processing module 902 includes a third processing unit 9021, a fourth processing unit 9022, a fifth processing unit 9023 and a sixth processing unit 9024:

[0101] The third processing unit 9021 is used to create a first information bit index set under multiple channel noise variances; the m elements of the first information bit index set correspond one-to-one to the m sub-channels with the highest reliability, m is the length of the extended bit string, and each bit of the extended bit string corresponds one-to-one to the m elements of the first information bit index set;

[0102] The fourth processing unit 9022 is used to take out n elements with the highest reliability corresponding to the subchannel in each of the first information bit index sets to form multiple second information bit index sets, where n is the length of the message bit string;

[0103] A fifth processing unit 9023 is configured to calculate a block error rate corresponding to the second information bit index set under each of the channel noise variances;

[0104] The sixth processing unit 9024 is configured to use the second information bit index set corresponding to the minimum block error rate as the information bit index set.

[0105] A communication system based on IDMA of scalable polar codes further includes a fourth processing module 905 and a fifth processing module 906:

[0106] a fourth processing module 905, configured to extract one index from the information bit index set obtained in the previous and current extended polar code encoding one by one, to obtain at least two bit protection pairs, where each bit pair includes a low reliability element and a high reliability element, where the low reliability element is an element having the lowest reliability of a corresponding subchannel in all the information bit index sets generated in the previous extended coding operation, and the high reliability index is an element having the highest reliability of a corresponding subchannel in the information bit index set obtained in the current extended coding operation;

[0107] The fifth processing module 906 is used to assign the bit value of the bit corresponding to the low reliability element in each of the bit protection pairs to the bit corresponding to the high reliability index.

[0108] The fourth processing module 905 includes a seventh processing unit 9051:

[0109] The seventh processing unit 9051 is used to calculate the block error rate after each bit protection pair is constructed. If the corresponding block error rate does not decrease when the current bit protection pair is constructed, the latest constructed bit protection pair is discarded and the construction of the bit protection pair is stopped.

[0110] It should be noted that, regarding the system in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0111] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0112] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A communication method based on IDMA of scalable polar codes, characterized in that: include: Acquire message bit strings of multiple users, where one message bit string is composed of multiple message bits input by one user; performing an extended coding operation on the message bit string, wherein an information bit index set is created according to the extended bit string, a bit value of each of the message bit strings is assigned to the extended bit string according to the information bit index set, and the assigned extended bit string is encoded by a preset polar code encoder to obtain an extended codeword, wherein the extended bit string is a bit string with an initial value of 0; The extended coding operation is cycled, and the obtained multiple extended code words are sequentially connected in the order of generation until a preset number of times is reached to obtain a complete code word; Each of the complete codewords is interleaved by an interleaver corresponding to the user to obtain a plurality of interleaved sequences, and each of the interleaved sequences is modulated by a mapper to obtain a plurality of modulated signals for communication.

2. The communication method based on IDMA of scalable polar code according to claim 1, characterized in that , the loop of the extended encoding operation comprises: The extended bit string after the value is assigned in the current extended coding operation is sequentially connected with the extended bit string after the value is assigned obtained in the previous extended coding operation in the order of generation, so as to obtain the input bit string of the current extended coding operation; The input bit string is encoded by a preset polar code encoder to obtain the extended codeword.

3. The communication method based on IDMA of scalable polar code according to claim 2, characterized in that , encoding the input bit string by a preset polar code encoder comprises: Calculating a mother code length according to the length of the input bit string, and constructing a mother code generation matrix corresponding to the mother code length; wherein the scale of the mother code generation matrix is ​​a power of 2; Based on the information bit index set and the length of the extended bit string, a part of the mother code generation matrix is ​​intercepted to obtain an extended generation matrix; The input bit string is input into a polar code encoder corresponding to the extended generation matrix to obtain the extended codeword.

4. The communication method based on IDMA of scalable polar code according to claim 1, characterized in that , the step of creating an information bit index set according to the extended bit string includes: Creating a first information bit index set under multiple channel noise variances; the m elements of the first information bit index set correspond one-to-one to the m sub-channels with the highest reliability, where m is the length of the extended bit string, and each bit of the extended bit string corresponds one-to-one to the m elements of the first information bit index set; Taking out n elements with the highest reliability corresponding to the subchannel in each of the first information bit index sets to form multiple second information bit index sets, where n is the length of the message bit string; Calculating a block error rate corresponding to the second information bit index set under each of the channel noise variances; The second information bit index set corresponding to the minimum block error rate is used as the information bit index set.

5. The communication method based on IDMA of scalable polar code according to claim 1, characterized in that After assigning the bit value of each message bit string to the extended bit string according to the information bit index set, the method further includes: taking out an index from the information bit index sets obtained in the previous and current extended polar code encoding one by one, to obtain at least two bit protection pairs, where each bit pair includes a low reliability element and a high reliability element, the low reliability element being an element having the lowest reliability of a corresponding subchannel in all the information bit index sets generated in the previous extended coding operation, and the high reliability index being an element having the highest reliability of a corresponding subchannel in the information bit index sets obtained in the current extended coding operation; The bit value of the bit corresponding to the low reliability element in each of the bit protection pairs is assigned to the bit corresponding to the high reliability index.

6. A communication system based on IDMA of scalable polar codes, characterized in that: include: An acquisition module, used for acquiring message bit strings of multiple users, wherein one message bit string is composed of multiple message bits input by one user; a first processing module, configured to perform an extended coding operation on the message bit string, wherein an information bit index set is created according to the extended bit string, a bit value of each of the message bit strings is assigned to the extended bit string according to the information bit index set, and the assigned extended bit string is encoded by a preset polar code encoder to obtain an extended codeword, wherein the extended bit string is a bit string with an initial value of 0; A second processing module is used to sequentially connect the obtained multiple extended code words in the order of generation until a preset number of times is reached to obtain a complete code word; The third processing module is used to perform interleaving processing on each of the complete codewords through an interleaver corresponding to the user to obtain multiple interleaving sequences, and each of the interleaving sequences is modulated by a mapper to obtain multiple modulated signals for communication.

7. The communication system based on scalable polar code IDMA according to claim 6, characterized in that: The third processing module comprises: A first processing unit, configured to sequentially connect the extended bit string after the value is assigned in the current extended coding operation with the extended bit string after the value is assigned obtained in the previous extended coding operation in a generation order, so as to obtain an input bit string for the current extended coding operation; The second processing unit encodes the input bit string by using a preset polar code encoder to obtain the extended codeword.

8. The communication system based on IDMA of scalable polar codes according to claim 7, characterized in that: The second processing unit comprises: A first processing subunit, configured to calculate a mother code length according to the length of the input bit string, and construct a mother code generation matrix corresponding to the mother code length; wherein the scale of the mother code generation matrix is ​​a power of 2; A second processing subunit is configured to intercept a part of the mother code generation matrix based on the information bit index set and the length of the extended bit string to obtain an extended generation matrix; The third processing subunit is configured to input the input bit string into a polar code encoder corresponding to the extended generation matrix to obtain the extended codeword.

9. The communication system based on IDMA of scalable polar codes according to claim 6, characterized in that: The first processing module comprises: A third processing unit is used to create a first information bit index set under multiple channel noise variances; the m elements of the first information bit index set correspond one-to-one to the m sub-channels with the highest reliability, m is the length of the extended bit string, and each bit of the extended bit string corresponds one-to-one to the m elements of the first information bit index set; a fourth processing unit, configured to extract n elements with the highest reliability corresponding to the subchannel in each of the first information bit index sets to form multiple second information bit index sets, where n is the length of the message bit string; a fifth processing unit, configured to calculate a block error rate corresponding to the second information bit index set under each of the channel noise variances; The sixth processing unit is used to use the second information bit index set corresponding to the minimum block error rate as the information bit index set.

10. The communication system based on IDMA of scalable polar codes according to claim 6, characterized in that: Also includes: a fourth processing module, configured to extract one index from the information bit index set obtained in the previous and current extended polar code encoding one by one, to obtain at least two bit protection pairs, where each bit pair includes a low reliability element and a high reliability element, where the low reliability element is an element having the lowest reliability of a corresponding subchannel in all the information bit index sets generated in the previous extended coding operation, and the high reliability index is an element having the highest reliability of a corresponding subchannel in the information bit index set obtained in the current extended coding operation; The fifth processing module is used to assign the bit value of the bit corresponding to the low reliability element in each of the bit protection pairs to the bit corresponding to the high reliability index.

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