Channel equalization method and device for short-wave spread spectrum communication, and RAKE receiver

Abstract

The invention relates to the technical field of spread spectrum communication, and discloses a channel equalization method for short-wave spread spectrum communication, which comprises the following steps: performing initial channel estimation and RAKE equalization according to a received complete receiving sequence to obtain an initial RAKE equalization result; performing channel decoding on the initial RAKE equalization result to obtain a decoding reconstruction sending sequence; and correcting channel estimation and RAKE equalization according to the decoding reconstruction sending sequence to obtain an RAKE equalization result for data decoding. According to the method, the error correction capability of channel coding can be fully utilized, and equalization errors caused by channel fading can be corrected. When deep fading occurs in a short-wave communication channel, the equalization accuracy of the RAKE receiver can be improved. The invention further discloses a channel equalization device for short-wave spread spectrum communication and the RAKE receiver.

Description

Technical Field

[0001] This application relates to the field of spread spectrum communication technology, for example, to a channel equalization method and apparatus for shortwave spread spectrum communication, and a RAKE receiver. Background Art

[0002] In a shortwave spread spectrum communication system, the function of a RAKE (rake) receiver is to separate multipath received signals, perform time delay and phase correction on the separated multipath received signals, and combine the corrected multipath components to improve the accuracy of signal reception in a multipath channel. However, due to the rapid change of the channel in shortwave communication, the fading amplitude and phase experienced by the transmitted signal of the transmitter on each channel propagation path fluctuate continuously, which in turn leads to a decrease in the equalization accuracy of the RAKE receiver. Therefore, in a rapidly changing shortwave channel, how to accurately track the channel change and then improve the detection accuracy of the RAKE receiver has become a key problem that needs to be solved urgently in the shortwave spread spectrum communication system.

[0003] To improve the detection accuracy of the RAKE receiver, related technologies disclose a receiver with RAKE receiving function and a satellite signal receiving method. The receiver with RAKE receiving function proposed by this method includes a plurality of signal receiving channels, and a rate conversion module, a local pseudo-code generation module, a detection and combination module, and a demodulation and decoding module connected to the plurality of signal receiving channels. In this method, the detection and combination module of the RAKE receiver performs multipath detection and data combination on the data output by the signal receiving channels, and demodulates and decodes the enhanced signal after data combination.

[0004] The disadvantage of the above method is that the receiver does not feedback the result output by the demodulation and decoding module, and cannot iteratively correct the errors in the demodulation and decoding result. When the shortwave communication channel undergoes deep fading, the demodulation and decoding accuracy of the above method will deteriorate severely. Summary of the Invention

[0005] To have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. The summary is not a general review, nor is it intended to identify key / important constituent elements or delineate the protection scope of these embodiments, but rather serves as a preface to the subsequent detailed description.

[0006] Embodiments of the present disclosure provide a channel equalization method and apparatus for shortwave spread spectrum communication, and a RAKE receiver to solve the problem of deterioration of RAKE equalization accuracy caused by rapid change of the communication channel in shortwave spread spectrum communication.

[0007] In some embodiments, the channel equalization method includes: performing initial channel estimation and RAKE equalization according to the received complete received sequence to obtain an initial RAKE equalization result; performing channel decoding on the initial RAKE equalization result to obtain a decoded and reconstructed transmission sequence; and correcting the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence to obtain a RAKE equalization result for data decoding.

[0008] In some embodiments, performing initial channel estimation and RAKE equalization according to the received complete received sequence y to obtain an initial RAKE equalization result includes: constructing a reconstructed sequence according to the complete received sequence y Performing initial channel estimation according to the pilot matrix P and the complete received sequence y and equalizing the initial channel estimation result to reconstruct each spread data segment element of the reconstructed sequence And completing the reconstruction of all spread data segment elements of the reconstructed sequence in an iterative manner; wherein, the pilot matrix P is constituted based on the reconstructed sequence Constituted. Constituted.

[0009] In some embodiments, performing initial channel estimation according to the pilot matrix P and the complete received sequence y and equalizing the initial channel estimation result to reconstruct each spread data segment element of the reconstructed sequence And completing the reconstruction of all spread data segment elements of the reconstructed sequence in an iterative manner, including: configuring an initial value of an iterative index variable m and a pilot sequence length L ; when m ≤ M - 1, obtaining an initial channel estimation vector according to the pilot matrix P and the pilot received signal vector y p ; when m ≤ M - 1, obtaining an initial channel estimation vector according to the pilot matrix P and the pilot received signal vector y pilot ; where the pilot matrix P is constituted by the (L where the pilot matrix P is based on the reconstructed sequence th (L s + mL M - L p + 1) to (L s + mL M ) elements, the pilot received signal vector y pilot is constituted by the (L s + mL M - L p + L h - 1) to (L s + mL M ) elements, L h represents the number of columns of the pilot matrix, L s and L M respectively represent the length of the synchronization header sequence of the complete received sequence y and the length of each spread data segment; determining The product of and is the lth tap correlation value vector and determine the log-likelihood ratio vector ξ of the l-th tap m,l , and determine the multi-path log-likelihood ratio vector according to the sum of the log-likelihood ratio vectors ξ m,l of all taps wherein represents the l-th element of the initial channel estimation vector , W represents the spreading codebook matrix, represents the received sequence to be equalized composed of the ((L s + mL M + l)-th to ((L s + mL M + l + L M - 1)-th elements of the complete received sequence y; perform hard decision on the multi-path log-likelihood ratio vector to obtain the decision index I m , and update the m-th spread data segment element of the reconstructed sequence to the I m -th row of the spreading codebook matrix W; in the case of m > M - 1, determine the updated reconstructed sequence as the initial RAKE equalization result for channel decoding.

[0010] In some embodiments, according to the hard decision rule, perform hard decision on the multi-path log-likelihood ratio vector to obtain the decision index I m , and update the m-th spread data segment element of the reconstructed sequence to the I m -th row of the spreading codebook matrix W, including: constructing a hard decision sequence of length B wherein the hard decision rule is that when the n-th element of is less than zero is zero, and when the n-th element of is greater than or equal to zero is 1; wherein the spreading codebook matrix W is a 2 B × M matrix; perform binary-to-decimal conversion on the hard decision sequence , and determine that the sum of the conversion result and 1 is the decision index I m ; update the m-th spread data segment element of the reconstructed sequence to the I m -th row of the spreading codebook matrix W.

[0011] In some embodiments, based on the pilot matrix P and the pilot received signal vector y pilot , obtain the initial channel estimation vector , including: based on (P H P) -1 PH The product with the pilot received signal vector y pilot to obtain the initial channel estimation vector

[0012] In some embodiments, the pilot matrix P is constructed in the following manner: Based on the reconstruction sequence the (L s + mL M - L p + 1) to (L s + mL M ) elements are used to construct the pilot vector p; a pilot matrix P of (L p - L h ) × L h is constructed, and the n-th row elements thereof are the row vector formed by p(n) to p(n + L h - 1), where p(t) represents the t-th pilot symbol of the pilot vector p.

[0013] In some embodiments, the channel estimation and RAKE equalization are corrected according to the decoded and reconstructed transmission sequence to obtain the RAKE equalization result for data decoding, including: According to the decoded and reconstructed transmission sequence and the complete received sequence y, channel estimation is performed and the channel estimation result is equalized to obtain the corrected multipath log-likelihood ratio vector and the calculation of all corrected multipath log-likelihood ratio vectors is completed through an iterative method.

[0014] In some embodiments, the channel estimation and RAKE equalization are corrected according to the decoded and reconstructed transmission sequence and the complete received sequence y to obtain the corrected multipath log-likelihood ratio vector and the calculation of all corrected multipath log-likelihood ratio vectors is completed through an iterative method, including: Configuring the initial value of the iterative index variable m; when m ≤ M - 1, according to the corrected pilot matrix P modi and the corrected pilot received signal vector to obtain the corrected channel estimation vector where the corrected pilot matrix P modi is based on the (L + mL s + 1) to (L M + mL s + L M + L p ) elements of the decoded and reconstructed transmission sequence, and the corrected pilot received signal vector is composed of the (L s + (m + 1)L M - L p + L h + 1) to (Ls +(m + 1)L M is composed of ) elements; determine and The product of is the l-th tap correction correlation value vector and determine the correction log-likelihood ratio vector of the l-th tap and according to the correction log-likelihood ratio vectors of all taps Determine the correction multipath log-likelihood ratio vector based on the sum value where represents the l-th element of, represents the corrected received sequence to be equalized composed of the (L s +(m + 1)L M -L p +L h +1) to (L s +(m + 1)L M ) elements; in the case of m > M, determine the correction multipath log-likelihood ratio vectors of all updated taps is the RAKE equalization result for data decoding.

[0015] In some embodiments, the channel equalization device includes a processor and a memory storing program instructions, and the processor is configured to execute the channel equalization method for shortwave spread-spectrum communication as described above when running the program instructions.

[0016] In some embodiments, the RAKE receiver includes: a receiver body; the channel equalization device for shortwave spread-spectrum communication as described above, installed on the receiver body.

[0017] The channel equalization method, device, and RAKE receiver for shortwave spread-spectrum communication provided by the embodiments of the present disclosure can achieve the following technical effects:

[0018] After obtaining the initial RAKE equalization result in the embodiments of the present disclosure, the result of its channel decoding is fed back to obtain the decoded and reconstructed transmission sequence, and the channel estimation and RAKE equalization are corrected. The error correction ability of the channel coding can be fully utilized to correct the equalization error caused by channel fading. When the shortwave communication channel experiences deep fading, the equalization accuracy of the RAKE receiver can be improved. The embodiments of the present disclosure can be applied to ultra-long-distance shortwave communication, overcome the severe ionospheric disturbance and multipath effect, and still ensure the reliable establishment and stable maintenance of the communication link under extreme conditions where the traditional RAKE receiving architecture cannot maintain the basic link.

[0019] The above general description and the following description are only exemplary and explanatory, and are not used to limit this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] One or more embodiments are illustrated by way of example in the corresponding drawings, and these illustrative descriptions and drawings do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements. The drawings do not constitute a scale limitation, and wherein:

[0021] Figure 1 is a schematic diagram of a channel equalization method for shortwave spread spectrum communication provided by an embodiment of the present disclosure;

[0022] Figure 2 is a schematic diagram of another channel equalization method for shortwave spread spectrum communication provided by an embodiment of the present disclosure;

[0023] Figure 3 is a schematic diagram of another channel equalization method for shortwave spread spectrum communication provided by an embodiment of the present disclosure;

[0024] Figure 4 is a schematic diagram of another channel equalization method for shortwave spread spectrum communication provided by an embodiment of the present disclosure;

[0025] Figure 5 is a schematic diagram of a transmitted signal frame provided by an embodiment of the present disclosure;

[0026] Figure 6 is a schematic diagram of a channel equalization device for shortwave spread spectrum communication provided by an embodiment of the present disclosure. Detailed implementation manners

[0027] In the embodiments of the present disclosure, the character " / " indicates that the objects before and after are in an "or" relationship. For example, A / B means: A or B.

[0028] The term "and / or" is an associative relationship describing an object, indicating that there can be three relationships. For example, A and / or B means: A or B, or, the three relationships of A and B.

[0029] The term "corresponding" may refer to an associative relationship or a binding relationship. A corresponding to B means that there is an associative relationship or a binding relationship between A and B.

[0030] Combined with Figure 2 shown, an embodiment of the present disclosure provides a channel equalization method for shortwave spread spectrum communication, including:

[0031] S01, the RAKE receiver performs initial channel estimation and RAKE equalization according to the received complete received sequence to obtain an initial RAKE equalization result.

[0032] S02, the RAKE receiver performs channel decoding on the initial RAKE equalization result to obtain a decoded and reconstructed transmitted sequence.

[0033] In this step, the RAKE receiver performs channel decoding on the initial RAKE equalization result to obtain a decoded and reconstructed transmission sequence, including: the RAKE receiver uses all multi-path log-likelihood ratio vectors for data decoding to obtain a data decoding result; the RAKE receiver re-performs short-wave spread-spectrum communication framing based on the data decoding result and the synchronization header sequence in the complete received sequence to obtain a decoded and reconstructed transmission sequence.

[0034] S03. The RAKE receiver corrects the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence to obtain a RAKE equalization result for data decoding.

[0035] By using the channel equalization method for short-wave spread-spectrum communication provided by the embodiments of the present disclosure, after obtaining the initial RAKE equalization result, the embodiments of the present disclosure feedback the result of its channel decoding to obtain a decoded and reconstructed transmission sequence and perform corrected channel estimation and RAKE equalization, which can make full use of the error correction ability of channel coding and correct the equalization errors caused by channel fading. When the short-wave communication channel undergoes deep fading, the accuracy of RAKE receiver equalization can be improved.

[0036] In addition, the paper "Low-Complexity OTSM Iterative RAKE Equalization Method in High-Speed Mobile Environments" (Journal of Communications, 2022, 43(10): 86-93) proposes a low-complexity iterative RAKE equalizer based on maximum ratio combining (MRC). This method designs a single-tap time-domain equalizer at the receiving end to obtain an estimated value of the delay-time-domain information symbol, and uses this estimated value as the initial value of the MRC iterative equalization algorithm to perform iterative equalization on the information symbol. The disadvantage of the above method is that it assumes that the multi-path channel remains constant, and the proposed MRC iterative equalization algorithm cannot perform iterative update of channel estimation. In a short-wave communication system, the above method cannot track the rapidly changing short-wave channel, resulting in a decrease in the reliability of the equalizer. However, the embodiments of the present disclosure use the decoded and reconstructed transmission sequence for iterative channel estimation. Therefore, the proposed channel equalization method can effectively track the rapid changes of the short-wave channel, and can perform accurate phase correction on each separated multi-path received signal, which helps to improve the accuracy of signal reception in the short-wave channel.

[0037] The embodiments of the present disclosure are applicable to ultra-long-distance short-wave communication, overcome severe ionospheric disturbances and multi-path effects, and can still ensure the reliable establishment and stable maintenance of the communication link under extreme conditions where the traditional RAKE receiving architecture cannot maintain the basic link.

[0038] Optionally, as shown in Figure 3 , the RAKE receiver performs initial channel estimation and RAKE equalization on the received complete received sequence y to obtain an initial RAKE equalization result, including:

[0039] S11, The RAKE receiver constructs a reconstructed sequence based on the complete received sequence y

[0040] In this step, the RAKE receiver constructs a reconstructed sequence according to the complete received sequence y It includes: The RAKE receiver determines the synchronization header sequence s according to the complete received sequence y; constructs a reconstructed sequence with a length of L s +mL M of the reconstructed sequence wherein, the first L elements of the reconstructed sequence s are the same as the first L s elements of the synchronization header sequence s, and the remaining elements of the reconstructed sequence take zero values.

[0041] S12, The RAKE receiver performs an initial channel estimation based on the pilot matrix P and the complete received sequence y and equalizes the initial channel estimation result to reconstruct each spread-spectrum data segment element of the reconstructed sequence, and completes the reconstruction of all spread-spectrum data segment elements of the reconstructed sequence in an iterative manner. Among them, the pilot matrix P is constituted based on the reconstructed sequence of the reconstructed sequence All spread-spectrum data segment elements are reconstructed. Among them, the pilot matrix P is constituted based on the reconstructed sequence constituted.

[0042] In this way, the embodiment of the present disclosure uses the reconstructed sequence to perform iterative channel estimation, which can effectively track the rapid change of the short-wave communication channel, thereby accurately correcting the phase of each separated received signal, and can significantly improve the accuracy of signal reception in the short-wave communication channel.

[0043] Optionally, as shown in Figure 4 The RAKE receiver performs an initial channel estimation based on the pilot matrix P and the complete received sequence y and equalizes the initial channel estimation result to reconstruct each spread-spectrum data segment element of the reconstructed sequence, and completes the reconstruction of all spread-spectrum data segment elements of the reconstructed sequence in an iterative manner, including: All spread-spectrum data segment elements are reconstructed, including: S21, The RAKE receiver configures the initial value of the iterative index variable m and the length L of the pilot sequence

[0044] S21, The RAKE receiver configures the initial value of the iterative index variable m and the length L of the pilot sequence p .

[0045] S22, When m ≤ M - 1, the RAKE receiver obtains the initial channel estimation vector according to the pilot matrix P and the pilot received signal vector y pilot , where the initial channel estimation vector wherein, the pilot matrix P is based on the reconstructed sequence of the (L s +mL M-L p +1) to (L s +mL M ) elements, the pilot received signal vector y pilot The first (L s +mL M -L p +L h -1) to (L s +mL M ) elements, L h Indicates the number of columns of the pilot matrix, L S , L M They represent the synchronization header sequence length of the complete received sequence y and the length of each spread spectrum data segment respectively.

[0046] S23, RAKE receiver determines and The product of is the l-th tap correlation value vector And determine the log-likelihood ratio vector ξ of the lth tap m,l , and according to the log-likelihood ratio vector ξ of all taps m,l The sum of the values determines the multipath log-likelihood ratio vector in, represents the initial channel estimation vector The lth element of , W represents the spread spectrum codebook matrix, Represents the (L s +mL M +l) to (L s +mL M +l+L M -1) elements of the received sequence to be equalized.

[0047] In this step, the RAKE receiver determines the log-likelihood ratio vector ξ of the lth tap m,l ,include: Among them, ξ m,l It is represented as a column vector of length B and its bth element is denoted as ξ m,l (b) The length is 2 B The column vector of which the i-th element is denoted by |·| represents the absolute value operation. In addition, the multipath log-likelihood ratio vector for in, is a column vector of length B.

[0048] S24, the RAKE receiver uses the hard decision rule to calculate the multipath log likelihood ratio vector Make a hard decision to obtain the decision index I m, and update the m-th spread-spectrum data segment element of the reconstructed sequence to the I-th m row of the spread-spectrum codebook matrix W.

[0049] S25. When m > M, the RAKE receiver determines that the updated reconstructed sequence is the initial RAKE equalization result for channel decoding.

[0050] In this way, the embodiment of the present disclosure reconstructs each spread-spectrum data segment element of the reconstructed sequence in an iterative manner, can effectively track the rapid change of the short-wave channel, thereby accurately correcting the phase of each separated multipath received signal, and improving the accuracy of signal reception in the short-wave channel.

[0051] In a specific embodiment, the RAKE receiver performs initial channel estimation and RAKE equalization according to the received complete received sequence y to obtain the initial RAKE equalization result, including:

[0052] S101. The RAKE receiver constructs a reconstructed sequence L with the same dimension as the complete received sequence based on the synchronization header sequence p .

[0053] S102. The RAKE receiver configures the initial value of the iteration index vector m to 0 and the pilot sequence length L p .

[0054] S103. The RAKE receiver determines whether m ≤ M - 1 holds; if so, execute S104, if not, execute S116.

[0055] S104. The RAKE receiver constructs a pilot vector p based on the elements from the (L + mL s - L M + 1) -th to the (L p + mL s ) -th of the reconstructed sequence M arranged in ascending order of indices. Among them, the number of columns of the pilot matrix P corresponding to the pilot vector p is L h .

[0056] S!05. The RAKE receiver constructs a pilot matrix P according to the pilot vector p. Among them, the n-th row of the pilot matrix P takes the row vector formed by arranging p(n) to p(n + L n - 1) in ascending order of indices.

[0057] S106. The RAKE receiver is based on the (L s + mL M - L p + Lh -(L - 1) to L s + mL M ) elements to construct the pilot received signal vector y in ascending order of index pilot .

[0058] S107, the RAKE receiver is based on (P H P) -1 P H and the pilot received signal vector y pilot to obtain the initial channel estimation vector

[0059] S108, the RAKE receiver is based on the initial channel estimation vector to the (L S + ML M + l) to (L S + ML M + l + L M - 1) elements of the complete received sequence y to construct the received sequence to be equalized for the l-th tap in ascending order of index

[0060] S109, the RAKE receiver multiplies the l-th element of the initial channel estimation vector by to obtain the correlation value vector for the l-th tap

[0061] S110, the RAKE receiver obtains the log-likelihood ratio vector ξ for the l-th tap according to the correlation value vector for the l-th tap m,l .

[0062] S111, the RAKE receiver obtains the multi-path log-likelihood ratio vector h ξ according to the sum value of the log-likelihood ratio vectors ξ m,l for all L taps i.e.,

[0063] S112, the RAKE receiver performs hard decision based on the multi-path log-likelihood ratio vector and obtains the hard decision sequence where, if the n-th element value of is less than zero, then it is determined that takes a value of zero, if the n-th element value of

[0064] S113, the RAKE receiver for Perform decimal representation to obtain the decision index I m .

[0065] S114, the RAKE receiver determines the I m -th row of the spreading codebook matrix W as the reconstruction sequence for the ((L s + mL M + 1)-th to (L s + mL M + L M )-th elements.

[0066] S115, the RAKE receiver updates m to m + 1 and returns to execute step S103.

[0067] S116, the RAKE receiver determines the updated reconstruction sequence as the initial RAKE equalization result for channel decoding.

[0068] Optionally, the RAKE receiver performs a hard decision on the multipath log-likelihood ratio vector to obtain the decision index I m , and updates the m-th spread data segment element of the reconstruction sequence to the I m -th row of the spreading codebook matrix W, including:

[0069] The RAKE receiver constructs a hard decision sequence of length B where the hard decision rule is that when the n-th element of is less than zero it is zero, and when the n-th element of is greater than or equal to zero it is 1. Where the spreading codebook matrix W is a 2 B × M matrix.

[0070] S116, the RAKE receiver determines the updated reconstruction sequence The RAKE receiver performs a binary-to-decimal conversion on the hard decision sequence and determines that the sum of the conversion result and 1 is the decision index I m .

[0071] The RAKE receiver updates the m-th spread data segment element of the reconstruction sequence to the I m -th row of the spreading codebook matrix W.

[0072] In this way, the embodiments of the present disclosure reconstruct each spread data segment element of the reconstruction sequence through the above hard decision rule, ensuring the accuracy and reliability of the spread data segment elements of the reconstructed reconstruction sequence and effectively tracking the rapid changes of the shortwave channel.

[0073] Optionally, the RAKE receiver obtains an initial channel estimation vector according to the pilot matrix P and the pilot received signal vector y pilot , and obtains an initial channel estimation vector including:

[0074] The RAKE receiver is based on (P H P) -1 P H and the product of the pilot received signal vector y pilot , and obtains an initial channel estimation vector

[0075] Optionally, the RAKE receiver constructs the pilot matrix P in the following manner:

[0076] The RAKE receiver is based on the (L + mL s - L M + I p ) to (L s + mL M ) elements of the reconstruction sequence to construct the pilot vector p.

[0077] The RAKE receiver constructs a pilot matrix P of (L p - L h )×L h , and the n-th row element thereof is the row vector formed by p(n) to p(n + L h - 1), and p(t) represents the t-th pilot symbol of the pilot vector p.

[0078] In this way, the embodiment of the present disclosure uses the reconstruction sequence for iterative channel estimation, which can effectively track the rapid change of the short-wave channel, so as to perform accurate phase correction on each separated multipath received signal, and helps to improve the accuracy of signal reception in the short-wave channel.

[0079] Optionally, the RAKE receiver corrects the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence, and obtains the RAKE equalization result for data decoding, including:

[0080] The RAKE receiver performs channel estimation on the decoded and reconstructed transmission sequence and the complete received sequence y and equalizes the channel estimation result to obtain a corrected multipath log-likelihood ratio vector and completes the calculation of all corrected multipath log-likelihood ratio vectors in an iterative manner.

[0081] In this way, the embodiment of the present disclosure uses the decoded and reconstructed transmission sequence Performing iterative channel estimation can effectively track the rapid changes of the short-wave channel, thereby accurately correcting the phase of each separated multipath received signal, which is beneficial to improving the accuracy of signal reception in the short-wave channel. In addition, the embodiments of the present disclosure can also overcome the severe ionospheric disturbances and multipath effects, and still be able to construct a reliable and stable communication link under extreme conditions where the traditional RAKE reception architecture cannot maintain the basic link.

[0082] Optionally, in combination with Figure 5 As shown, the RAKE receiver performs channel estimation on the decoded and reconstructed transmission sequence and the complete received sequence y and equalizes the channel estimation result to obtain the corrected multipath log-likelihood ratio vector and completes the calculation of all corrected multipath log-likelihood ratio vectors in an iterative manner, including:

[0083] S31, the RAKE receiver configures the initial value of the iterative index variable m.

[0084] S32, when m ≤ M - 1, the RAKE receiver obtains the corrected channel estimation vector modi based on the corrected pilot matrix P and the corrected pilot received signal vector where the corrected pilot matrix P modi is composed of the (L + mL s + 1) to (L M + mL s + L M + L p ) elements of the decoded and reconstructed transmission sequence <C and the corrected pilot received signal vector s is composed of the (L M + (m + 1)L p - L h + L s + 1) to (L M ) elements of the complete received sequence y.

[0085] S33, the RAKE receiver determines the product of and as the l-th tap corrected correlation value vector and determines the corrected log-likelihood ratio vector of the l-th tap and determines the corrected multipath log-likelihood ratio vector based on the sum value of the corrected log-likelihood ratio vectors of all taps where represents the l-th element ofs +(m + 1)L M -L p +L h +1) to (L s +(m + 1)L M ) elements to form a modified received sequence to be equalized.

[0086] In this step, the RAKE receiver determines the modified log-likelihood ratio vector of the l-th tap including: where is represented as a column vector of length B and its b-th element is denoted as is a column vector of length 2 B and its i-th element is denoted as In addition, the modified multipath log-likelihood ratio vector is where is a column vector of length B.

[0087] S34. In the case of m > M, the RAKE receiver determines the modified multipath log-likelihood ratio vectors of all taps for which the update is complete as the RAKE equalization result for data decoding.

[0088] In a specific embodiment, the RAKE receiver corrects the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence to obtain the RAKE equalization result for data decoding, including:

[0089] S201. The RAKE receiver configures the initial value of the iteration index vector m.

[0090] S202. The RAKE receiver determines whether m ≤ M - 1 holds; if so, it executes S203, if not, it executes S210.

[0091] S203. Based on of the (L s + mL M + 1) to (L s + mL M + L p ) elements, construct the modified pilot vector p modi in ascending order of indices, where the pilot vector p modi [[ID=6�]]corresponds to a pilot matrix with L columns h .

[0092] S204. The RAKE receiver is based on the (L s +(m + 1)L M -L p +Lh +1) to (L s +(m+1)L M ) elements, and construct the modified pilot reception signal vector according to the ascending order of index

[0093] S205, RAKE receiver based on ((P modi ) H P modi ) -1 (P modi ) H and the modified pilot received signal vector The product of , obtains the modified channel estimation vector

[0094] S206, the RAKE receiver modifies the channel estimation vector Based on the complete received sequence y S +ML M +l) to (L S +ML M +l+L M -1) elements are arranged in ascending order of index to form the modified equalized receiving sequence of the lth tap

[0095] S207, the RAKE receiver modifies the channel estimation vector The lth element of and the lth tap's received sequence to be equalized The conjugate multiplication of the l-th tap is used to obtain the modified correlation value vector

[0096] S208, the RAKE receiver modifies the correlation value vector of the lth tap Get the modified log-likelihood ratio vector of the lth tap

[0097] S209, RAKE receiver according to all L h Modified log-likelihood ratio vector of taps The sum of the values of

[0098] S210, the RAKE receiver determines the updated modified multipath log-likelihood ratio vectors of all taps is the RAKE equalization result used for data decoding.

[0099] In practical applications, the channel equalization method for shortwave spread spectrum communication specifically performs the following steps:

[0100] Step 1: Perform initial channel estimation and RAKE equalization on the received complete received sequence to obtain the initial RAKE equalization result.

[0101] The format of the shortwave spread-spectrum data frame transmitted by the transmitter is as Figure 5 shown. The synchronization header sequence s is [-1 1 1 1 -1], and the length L s of the synchronization header sequence takes a value of 5. The information sequence is [0 1], channel coding uses a 2-to-4 repetition code, and the encoded sequence is [0 1 0 1]. Spread spectrum uses a 2-to-4 Walsh spread spectrum, and the spread spectrum codebook matrix W is

[0102] The number of effective bits B carried by each spread-spectrum data segment is 2, the number M of spread-spectrum data segments is 2 segments, the first spread-spectrum data segment sequence is [-1 -1 i -1 i -1 i], and the second spread-spectrum data segment sequence is

[0103] [-1 -1 i -1 i -1 i]. The length L M of each spread-spectrum data segment takes a value of 4, and the length L h of the shortwave multipath channel takes a value of 2. The complete received sequence y received by the RAKE receiver is

[0104]

[0105] The RAKE receiver constructs a reconstructed sequence of length 13 based on the received complete received sequence y The reconstructed sequence has the same values for the first 5 elements as the first 5 elements of the synchronization header sequence s. The remaining elements of the reconstructed sequence take a value of 0. In this embodiment, the reconstructed sequence is [-1 1 1 1 -1 0 0 0 0 0 0 0 0] T . Set the iteration index variable m to zero.

[0106] The length L p of the pilot sequence used by the RAKE receiver for channel estimation is 4. Take the 2nd to 5th elements of the reconstructed sequence and arrange them in ascending order of index to form the pilot vector p. Then, construct a pilot matrix P of size 2 rows and 2 columns. In this embodiment, the pilot vector p is [1 1 1 -1] T , and the pilot matrix P is

[0107] The RAKE receiver arranges the elements y(4) to y(5) in the complete received sequence y in ascending order of index to form the pilot received signal vector y pilot . Then the matrix (P H P)-1 P H Multiply by the vector y pilot to obtain the initial channel estimation vector In this embodiment, the pilot received signal vector y pilot is [0.2051 -0.7999+0.0008i] T , and the initial channel estimation vector is [-0.1487+0.0002i -0.1487+0.0002i] T .

[0108] For the l-th element of the initial channel estimation vector the RAKE receiver arranges the elements y(5 + l) to y(8 + l) in the complete received sequence y in ascending order of index to form the received sequence to be equalized for the l-th tap In this embodiment, the received sequence to be equalized for the first tap is

[0109] [-0.1967+0.0020i 0.2976-0.5004i 0.0041-0.1993i-0.0027-0.1996i] T , and the received sequence to be equalized for the second tap is

[0110] [0.2976-0.5004i 0.0041-0.1993i-0.0027-0.1996i-0.5001+0.3040i] T . Multiply the matrix by the conjugate of the received sequence to be equalized for the l-th tap to obtain the correlation value vector for the l-th tap In this embodiment, the correlation value vector for the first tap is

[0111] [0.0452-0.0430i-0.1629+0.0450i 0.0451-0.0450i-0.0443+0.0444i] T , and the correlation value vector for the second tap is [-0.0008+0.1478i 0.0301+0.0002i 0.1488-0.0004i-0.0007+0.1498i] T . Then, obtain the log-likelihood ratio vector ξ output for the l-th tap 0,l . In this embodiment, the log-likelihood ratio vector ξ output for the first tap 0,1 is [-0.1053 0.1053]​T , the log-likelihood ratio vector ξ output by the second tap 0,2 is [0.0020 0.0010] T . The RAKE receiver

[0112] The RAKE receiver calculates the multipath log-likelihood ratio vector In this embodiment, the multipath log-likelihood ratio vector is [-0.1033 0.1063] T . Then, a hard decision sequence of length 2 is constructed The hard decision sequence For any nth element of The value is determined as follows: If the nth element value of the multipath log-likelihood ratio vector is less than 0, then the value is 0, otherwise the value is 1. In this embodiment, the hard decision sequence is [0 1]. Then, the hard decision sequence is converted from binary to decimal representation, and 1 is added to the decimal representation result to obtain the decision index I m which is 2. The values of the 6th to 9th elements of the reconstruction sequence are the second row of the spreading codebook matrix W, which is [-1 -1i -1i -1i]. At this time, the reconstruction sequence is updated to [-1 1 1 1 -1 -1 -1i -1i -1i 0 0 0 0] T .

[0113] The RAKE receiver increments the iteration index variable m by 1, that is, m takes the value 1. Take the 6th to 9th elements of the reconstruction sequence and arrange them in ascending order of the index to form the pilot vector p. Then, a pilot matrix P of size 2 rows and 2 columns is constructed. In this embodiment, the pilot vector p is [-1 -1i -1i -1i] T , and the pilot matrix P is

[0114] The RAKE receiver arranges the elements y(8) to y(9) in the complete received sequence y in ascending order of the index to form the pilot received signal vector y pilot , and then multiplies the vector y by the matrix (P H P) -1 P H to obtain the initial channel estimation vector pilot . In this embodiment, the pilot received signal vector y is [0.0041 -0.1993i -0.0027 -0.1996i] pil T, the initial channel estimation vector is [-0.2002 + 0.1988i -0.0005 + 0.1961i] T .

[0115] The RAKE receiver arranges the elements y(9 + l) to y(12 + l) in the complete received sequence y in ascending order of index for the l-th element of the initial channel estimation vector to form the received sequence to be equalized for the l-th tap In this embodiment, the received sequence to be equalized for the first tap is [-0.5001 + 0.3040i 0.2993 - 0.5014i -0.0026 - 0.2003i -0.0029 - 0.1981i] , and the received sequence to be equalized for the second tap T is [0.2993 - 0.5014i -0.0026 - 0.2003i -0.0029 - 0.1981i 0.0014 + 0.3021i] . Multiply the matrix T with the conjugate of the received sequence to be equalized for the l-th tap to obtain the correlation value vector for the l-th tap In this embodiment, the correlation value vector for the first tap is [-0.1200 - 0.1205i -0.2823 + 0.2763i -0.1193 - 0.1215i -0.1206 + 0.1200i] , and the correlation value vector for the second tap T is [0.0980 + 0.0004i 0.0976 - 0.0395i 0.1002 - 0.1958i 0.0981 + 0.0013i] . Then, obtain the log-likelihood ratio vector ξ output from the l-th tap T . In this embodiment, the log-likelihood ratio vector ξ output from the first tap 1,l is [-0.2247 0.2247] 1,1 , and the log-likelihood ratio vector ξ output from the second tap T is [0.1146 -0.1146] 1,2 . T .

[0116] The RAKE receiver calculates the multipath log-likelihood ratio vector In this embodiment, the multipath log-likelihood ratio vector is [-0.1101 0.1101] T . Then, construct a hard decision sequence of length 2 Hard decision sequence Any nth element of The value is determined as follows: If the nth element of the multipath log-likelihood ratio vector is less than 0, then the value is 0, otherwise the value is 1. In this embodiment, the hard decision sequence is [0 1]. Then, the hard decision sequence is converted from binary to decimal representation, and 1 is added to the decimal representation result to obtain the decision index I m which is 2. The 8th to 11th elements of the reconstructed sequence take the values of the second row of the spreading codebook matrix W, which is [-1 -1i -1i -1i]. At this time, the reconstructed sequence is updated to [-1 1 1 1 -1 -1 -1i -1i -1i -1 -1i -1i -1i] T .

[0117] Step 2, The RAKE receiver performs channel decoding on the initial RAKE equalization result to obtain the decoded and reconstructed transmission sequence.

[0118] The RAKE receiver uses all the multipath log-likelihood ratio vectors and to perform data decoding and obtains the decoded sequence [0 1].[[]END]]

[0119] The RAKE receiver re-performs shortwave spread-spectrum communication framing according to the data decoding result and the synchronization header sequence s, and the obtained decoded and reconstructed transmission sequence is [-1 1 1 1 -1 -1 -1i -1i -1i -1 -1i -1i -1i] T .

[0120] Step 3, The RAKE receiver corrects the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence to obtain the RAKE equalization result for data decoding.

[0121] The RAKE receiver sets the iteration index variable m to zero. Then, it takes the 6th to 9th elements from the decoded and reconstructed transmission sequence and arranges them in ascending order of the index to obtain the corrected pilot vector p modi . Then, a corrected pilot matrix P of size 2 rows and 2 columns is constructed modi . In this embodiment, the corrected pilot vector p modi is [-1 -1i -1i -1i] T , and the corrected pilot matrix P modi is

[0122] The RAKE receiver arranges the elements y(6) to y(7) in the complete received sequence y in ascending order of indices to form a modified pilot received signal vector Then multiply it with the matrix ((P modi ) H P modi ) -1 (P modi ) H by the vector to obtain a modified channel estimation vector In this embodiment, the modified pilot received signal vector is [-0.1967 - 0.0020i 0.2976 - 0.5004i] T , and the modified channel estimation vector is [-0.4963 - 0.0021i 0.0041 + 0.2997i] T .

[0123] For the l-th element of the modified channel estimation vector , arrange the elements y(5 + l) to y(8 + l) in the complete received sequence y in ascending order of indices to form a modified received sequence to be equalized for the l-th tap In this embodiment, the modified received sequence to be equalized for the first tap is [-0.1967 - 0.0020i -0.2976 - 0.5004i 0.0041 - 0.1993i -0.0027 - 0.1996i] T , and the modified received sequence to be equalized for the second tap is [0.2976 - 0.5004i 0.0041 - 0.1993i -0.0027 - 0.1996i -0.5001 + 0.3040i] T . Multiply the matrix with the conjugate of the modified received sequence to be equalized for the l-th tap to obtain a modified correlation value vector for the l-th tap In this embodiment, the modified correlation value vector for the first tap is [-0.1503 + 0.1440i 0.5434 - 0.1517i -0.1500 + 0.1507i 0.1474 - 0.1487i] T , and the modified correlation value vector for the second tap is [0.2979 - 0.0021i -0.0003 - 0.0607i -0.0044 - 0.2998i 0.3019 - 0.0023i]T Then, the modified log-likelihood ratio vector of the l-th tap output is obtained In this embodiment, the modified log-likelihood ratio vector of the first tap output is [-0.3515 0.3515] T , and the modified log-likelihood ratio vector of the second tap output is [0.0041 0.0021] T .

[0124] The RAKE receiver calculates the modified multipath log-likelihood ratio vector In this embodiment, the modified multipath log-likelihood ratio vector is [-0.3475 0.3536] T Increment the iteration index variable m by 1, i.e., m takes the value of 1.

[0125] The RAKE receiver extracts the 10th to 13th elements from the decoded and reconstructed transmission sequence Arrange them in ascending order of the index to obtain the modified pilot vector p modi Then, construct a modified pilot matrix P of size 2 rows and 2 columns modi In this embodiment, the modified pilot vector p modi is [-1 -1i -1i -1i] T , and the modified pilot matrix P modi is

[0126] The RAKE receiver arranges the elements y(10) to y(11) in the complete received sequence y in ascending order of the index to form the modified pilot received signal vector Then multiply the vector by the matrix ((P modi )) H P modi ) -1 (P modi ) H to obtain the modified channel estimation vector In this embodiment, the modified pilot received signal vector is [-0.5001 + 0.3040i 0.2993 - 0.5014i] , and the modified channel estimation vector T is [0.8024 - 0.0030i -0.3010 + 0.3023i] . T .

[0127] For the l-th element of the modified channel estimation vector ​The RAKE receiver arranges the elements y(9 + l) to y(12 + l) in the complete received sequence y in ascending order of the index to form the corrected received sequence to be equalized for the l-th tap. In this embodiment, the corrected received sequence to be equalized for the first tap is [-0.5001 + 0.3040i 0.2993 - 0.5014i -0.0026 - 0.2003i -0.0029 - 0.1981i]. T , and the corrected received sequence to be equalized for the second tap is [0.2993 - 0.5014i -0.0026 - 0.2003i -0.0029 - 0.1981i 0.0014 + 0.3021i]. T . Multiply the matrix by the conjugate of the corrected received sequence to be equalized for the l-th tap to obtain the corrected correlation value vector for the l-th tap In this embodiment, the corrected correlation value vector for the first tap is [0.0026 + 0.4838i 1.1234 + 0.0040i -0.0010 + 0.4844i 0.4839 - 0.0024i]. T , and the corrected correlation value vector for the second tap is [0.1508 + 0.1506i 0.2114 + 0.0884i 0.4546 - 0.1492i 0.1497 + 0.1521i]. T . Then, obtain the corrected log-likelihood ratio vector output for the l-th tap In this embodiment, the corrected log-likelihood ratio vector output for the first tap is [-0.6391 0.6391]. T , and the corrected log-likelihood ratio vector output for the second tap is [0.2493 -0.2493]. T .

[0128] The RAKE receiver calculates the corrected multipath log-likelihood ratio vector In this embodiment, the corrected multipath log-likelihood ratio vector is [-0.3897 0.3897]. T .

[0129] Step 4, the RAKE receiver uses all the corrected multipath log-likelihood ratio vectors and (i.e., the RAKE equalization result) to perform data decoding and obtain the final decoding result

[01] .

[0130] Combined withFigure 6 As shown in Figure 6 , an embodiment of the present disclosure provides a channel equalization device 100 for short-wave spread-spectrum communication, including a processor 700 and a memory 701. Optionally, the device 100 may further include a communication interface 702 and a bus 703. Among them, the processor 700, the communication interface 702, and the memory 701 can complete mutual communication through the bus 703. The communication interface 702 can be used for information transmission. The processor 700 can call the logical instructions in the memory 701 to execute the channel equalization method for short-wave spread-spectrum communication in the above embodiment.

[0131] In addition, when the logical instructions in the above-mentioned memory 701 are implemented in the form of a software functional unit and sold or used as an independent product, they can be stored in a computer-readable storage medium.

[0132] The memory 701, as a computer-readable storage medium, can be used to store software programs and computer-executable programs, such as the program instructions / modules corresponding to the method in the embodiment of the present disclosure. The processor 700 executes functional applications and data processing by running the program instructions / modules stored in the memory 701, that is, implements the channel equalization method for short-wave spread-spectrum communication in the above embodiment.

[0133] The memory 701 may include a storage program area and a storage data area. Among them, the storage program area can store an operating system and application programs required for at least one function; the storage data area can store data created according to the use of the terminal device, etc. In addition, the memory 701 may include a high-speed random access memory and may also include a non-volatile memory.

[0134] An embodiment of the present disclosure provides a RAKE receiver, including: a receiver body, and the above-mentioned channel equalization device 100 for short-wave spread-spectrum communication. The channel equalization device 100 for short-wave spread-spectrum communication is installed on the receiver body. The installation relationship described here is not limited to being placed inside the receiver body, but also includes installation connections with other components of the RAKE receiver, including but not limited to physical connections, electrical connections, or signal transmission connections, etc. Those skilled in the art can understand that the channel equalization device 100 for short-wave spread-spectrum communication can be adapted to a feasible receiver body, and then implement other feasible embodiments.

[0135] An embodiment of the present disclosure provides a computer-readable storage medium storing computer-executable instructions, and the computer-executable instructions are set to execute the above-mentioned channel equalization method for short-wave spread-spectrum communication.

[0136] The technical solution of the embodiments of the present disclosure can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes one or more instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the channel equalization method described in the embodiments of the present disclosure. The foregoing storage medium may be a non-transitory storage medium, such as: a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk, or an optical disc, and other media that can store program codes.

[0137] The above description and the drawings fully illustrate the embodiments of the present disclosure so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process, and other changes. Embodiments only represent possible variations. Unless explicitly required, separate components and functions are optional, and the order of operations can vary. Parts and features of some embodiments may be included in or substituted for parts and features of other embodiments. Moreover, the terms used in this application are only for describing embodiments and are not used to limit the claims. As used in the description of the embodiments and the claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to also include the plural forms. Similarly, as used in this application, the term "and / or" refers to any and all possible combinations including one or more of the associated listed items. Additionally, when used in this application, the term "comprise" and its variants "comprises" and / or "comprising" etc. mean the presence of the stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups of these. Without further limitation, an element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, or device including the element. In this document, each embodiment may focus on the differences from other embodiments, and the same or similar parts among the embodiments may be referred to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, the relevant parts may refer to the description of the method part.

Claims

1. A channel equalization method for short-wave spread-spectrum communication, characterized in that, Comprising: Performing initial channel estimation and RAKE equalization according to the received complete reception sequence to obtain an initial RAKE equalization result; Performing channel decoding on the initial RAKE equalization result to obtain a decoded and reconstructed transmission sequence; Correcting the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence to obtain a RAKE equalization result for data decoding.

2. The equalization method according to claim 1, characterized in that, Performing initial channel estimation and RAKE equalization according to the received complete reception sequence y to obtain an initial RAKE equalization result, including: Construct a reconstructed sequence based on the complete received sequence y Perform initial channel estimation based on the pilot matrix P and the complete received sequence y, and equalize the initial channel estimation result to reconstruct the reconstruction sequence for each spread data segment element, and complete the reconstruction of the reconstruction sequence in an iterative manner for all spread data segment elements; wherein, the pilot matrix P is based on the reconstruction sequence constituted.

3. The equalization method according to claim 2, characterized in that, Perform initial channel estimation based on the pilot matrix P and the complete received sequence y, and equalize the initial channel estimation result to reconstruct the reconstruction sequence Reconstruct each spread-spectrum data segment element, and complete the reconstruction of the reconstruction sequence in an iterative manner Reconstruction of all spread-spectrum data segment elements, including: Configure the initial value of the iterative index variable m and the length L of the pilot sequence p ; When m ≤ M - 1, based on the pilot matrix P and the pilot received signal vector y pilot , an initial channel estimation vector is obtained where the pilot matrix P is based on the reconstruction sequence of the (L s + mL M - L p + 1)th to (L s + mL M )th elements, and the pilot received signal vector y pilot consists of the (L s + mL M - L p + L h - 1)th to (L s + mL M )th elements of the complete received sequence y. L h represents the number of columns of the pilot matrix, and L s , L M respectively represent the length of the synchronization header sequence of the complete received sequence y and the length of each spread data segment; Determine The product with is the correlation value vector of the l-th tap and determine the log-likelihood ratio vector ξ of the l-th tap m,l , and based on the log-likelihood ratio vectors ξ of all taps m,l Determine the multipath log-likelihood ratio vector according to the sum value where represents the l-th element of the initial channel estimation vector , W represents the spreading codebook matrix represents the (L s + mL M + l)-th to (L s + mL M + l + L M - 1) elements to form a receive sequence to be equalized; Perform hard decision on the multipath log-likelihood ratio vector according to the hard decision rule to obtain the decision index I m , and update the m-th spreading data segment element of the reconstructed sequence to the I-th row of the spreading codebook matrix W m ; In the case of m > M, determine the updated and completed reconstruction sequence Is the initial RAKE equalization result for channel decoding.

4. The equalization method according to claim 3, characterized in that, According to the hard decision rule, for the multipath log-likelihood ratio vector perform hard decision to obtain the decision index I m , and update the m-th spread-spectrum data segment element of the reconstructed sequence to the I m -th row of the spread-spectrum codebook matrix W, including: Construct a hard decision sequence of length B wherein, the hard decision rule is that when the n-th element of is less than zero it is zero, and when the n-th element of is greater than or equal to zero it is 1; wherein, the spreading codebook matrix W is a 2 B ×M matrix For the hard decision sequence perform binary to decimal conversion, and determine that the sum of the conversion result and 1 is the decision index I m ; Update the m-th spread-spectrum data segment element of the reconstructed sequence to the I-th m row of the spread-spectrum codebook matrix W.

5. The equalization method according to claim 3, characterized in that, According to the pilot matrix P and the pilot received signal vector y pilot , an initial channel estimation vector is obtained including: Based on (P H P) -1 P H and the pilot received signal vector y pilot to obtain an initial channel estimation vector 6. The equalization method according to claim 3, wherein Constructing a pilot matrix P in the following manner: Based on the reconstructed sequence the (L s + mL M - L p + 1)th to the (L s + mL M )th elements to construct a pilot vector p; Construct (L p -L h ) × L h of the pilot matrix P, and the elements of its n-th row are the row vector formed by p(n) to p(n + L h - 1), and p(t) represents the t-th pilot symbol of the pilot vector p.

7. The equalization method according to claim 3, characterized in that Correcting the channel estimation and RAKE equalization according to the decoded and reconstructed transmission sequence to obtain a RAKE equalization result for data decoding, including: Reconstruct the transmitted sequence according to decoding Perform channel estimation on the complete received sequence y and equalize the channel estimation result to obtain a corrected multipath log-likelihood ratio vector And complete the calculation of all corrected multipath log-likelihood ratio vectors in an iterative manner.

8. The equalization method according to claim 7, characterized in that Reconstruct the transmitted sequence according to decoding Perform channel estimation on the complete received sequence y and equalize the channel estimation result to obtain the corrected multipath log-likelihood ratio vector And complete the calculation of all corrected multipath log-likelihood ratio vectors in an iterative manner, including: Configuring an initial value of an iterative index variable m; When m ≤ M - 1, according to the modified pilot matrix P modi and the modified pilot received signal vector obtain the modified channel estimation vector wherein, the modified pilot matrix P modi is based on the (L (L s + mL M + 1) to (L s + mL M + L p ) elements of the decoded and reconstructed transmission sequence, and the modified pilot received signal vector is composed of the ((L s + (m + 1)L M - L p + L h + 1) to (L s + (m + 1)L M ) elements of the complete received sequence y; Determine The product with is the l-th tap correction correlation value vector and determine the correction log-likelihood ratio vector for the l-th tap and based on the correction log-likelihood ratio vectors for all taps determine the corrected multipath log-likelihood ratio vector based on the sum value where denotes the l-th element of and s +(m + 1)L M -L p +L h +1) to (L s +(m + 1)L M ) elements form the corrected received sequence to be equalized In the case of m > M - 1, determine the corrected multipath log-likelihood ratio vectors for all the taps for which the update is complete. This is the RAKE equalization result for data decoding.

9. A channel equalization device for short-wave spread-spectrum communication, comprising a processor and a memory storing program instructions, characterized in that, The processor is configured to execute the channel equalization method for short-wave spread-spectrum communication according to any one of claims 1 to 8 when running the program instructions.

10. A RAKE receiver, characterized in that, Comprising: A receiver body; The channel equalization device for short-wave spread-spectrum communication according to claim 9, installed on the receiver body.

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