A frequency deviation estimation method and system for WIFI6 system

Abstract

This invention discloses a frequency offset estimation method and system for WIFI6 systems, belonging to the field of frequency offset estimation technology. This invention constructs a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and performs coarse frequency offset estimation based on the constructed new sequence, obtaining the coarse frequency offset estimate value through only one angle calculation. Compared with existing technologies, while maintaining the same frequency offset estimation range, the estimation accuracy and speed are significantly improved due to the use of a higher resolution sequence.

Description

Technical Field

[0001] The present invention belongs to the technical field of frequency deviation estimation, and specifically relates to a frequency deviation estimation method and system for a WIFI6 system. Background Art

[0002] Since OFDM technology is very sensitive to frequency deviation, the receiver must perform frequency deviation estimation and phase compensation after completing timing synchronization. In the WIFI6 standard based on OFDM communication, specific training sequences are inserted into the preamble, such as short training sequences and long training sequences, which are used to complete the timing synchronization, frequency synchronization, channel estimation, etc. of the receiver. At the same time, in order to achieve an increase in frame capacity, the data field of WIFI6 uses a narrower subcarrier spacing than the preamble part, which has a higher frequency resolution.

[0003] Usually, the method for frequency offset estimation and compensation at the receiving end uses a short training sequence LSTF for rough frequency offset estimation and compensation. For example, in Chinese patent application document CN 112866163 B, a method for residual frequency offset estimation for WiFi services includes the following steps: step S1, rough frequency offset estimation and compensation is achieved through a short training sequence; step S2, fine frequency offset estimation and compensation is achieved through a long training sequence; step 3, residual frequency offset estimation and compensation is performed on the cyclic prefix part of the symbol; step S4, channel estimation is performed on the received data after the residual frequency offset of the cyclic prefix part of the symbol is compensated; step 5, phase difference compensation is performed within each data symbol until all data symbols are processed. Its rough frequency offset estimation directly uses a short training sequence, that is, directly uses a short preamble code for estimation, which has low estimation accuracy, and there are multiple complex angle calculation operations and averaging operations, which is time-consuming and inefficient. Summary of the invention

[0004] The present invention aims to solve the technical problems existing in the prior art, and provides a frequency offset estimation method and system for a WIFI6 system. A new sequence with a length greater than or equal to a preset length L is constructed based on a short training sequence, and a rough frequency offset estimation is performed based on the constructed new sequence, and a rough frequency offset estimation value is obtained by only one angle calculation. Compared with the prior art, on the basis of the unchanged frequency offset estimation range, due to the construction of a new sequence with a longer length and a more clever and fast method of obtaining, both the estimation accuracy and the estimation speed are significantly improved.

[0005] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0006] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0007] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0008] Step 3, perform fine frequency offset estimation;

[0009] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0010] Preferably, in step 1, a new sequence with a length greater than or equal to a preset length L is constructed in the time domain based on the short training sequence to perform coarse frequency offset estimation.

[0011] Preferably, in step 1, based on the short training sequence, two adjacent repeated new sequence segments with lengths greater than or equal to a preset length L are constructed in the time domain, and a coarse frequency offset estimation value is obtained by calculating the angle, and the length of the new sequence segment is greater than the short training sequence symbol length.

[0012] Preferably, in step 1, in the short training sequence LSTF sequence, the length of the new sequence is determined according to the number of sampling points D of the short codewords.

[0013] Preferably, two repeated new sequence segments with a length of L=9D are selected, and the interval between the two new sequence segments is ensured to be the length of a short code element.

[0014] Preferably, the coarse frequency offset estimation is calculated using the following formula:

[0015]

[0016] in,

[0017] f sts is the coarse frequency offset estimate;

[0018] Fs represents the sampling rate; if the sampling rate is 20M, then F S =20e 6 ;

[0019] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0020] n represents the index of the number of sampling points in the selected sequence segment;

[0021] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0022] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0023] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0024] conj() stands for conjugate operation;

[0025] arctan() represents the angle operation.

[0026] Preferably, step 5 is further included after step 4, performing residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0027] Preferably, in step 5, a residual phase deviation estimation value of each symbol is obtained in the frequency domain based on a received signal on a pilot subcarrier of each symbol and a known reference signal.

[0028] Preferably, the residual phase deviation estimate of the lth symbol is calculated using the following formula:

[0029]

[0030] in,

[0031] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0032] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0033] l is the index of the data symbol of the data field;

[0034] Y l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0035] REF l (k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0036] φ l represents the residual phase deviation estimated for the lth data symbol.

[0037] Preferably, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0038]

[0039] in,

[0040] k is the index of the subcarrier in the frequency domain of each data symbol;

[0041] l is the index of each data symbol in the data field;

[0042] φ l represents the estimated residual phase deviation of the lth data symbol;

[0043] Y l (k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0044] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0045] Preferably, in step 3, a long training sequence LLTF is used to perform fine frequency offset estimation.

[0046] Preferably, in step 3, a long training sequence LLTF is used, and a fine frequency offset estimation value is obtained by calculating an angle using long code elements of two adjacent repeated long training sequences in the time domain.

[0047] Preferably, in step 3, a long training sequence LLTF is used, and a fine frequency offset estimation value is obtained by calculating an angle using long code elements of two adjacent repeated long training sequences in the time domain. The fine frequency offset estimation is specifically calculated using the following formula:

[0048]

[0049] in

[0050] f lts is the fine frequency deviation estimate;

[0051] Fs represents the sampling rate, in Hz; if the sampling rate is 20M, then F S =20e 6 ;

[0052] DD represents the number of sampling points of the long training sequence codeword, DD = 3.2 × 1e -6 ×F S ;

[0053] j represents the index of the sampling point number in the long training sequence codeword;

[0054] dd(j) represents the data of the jth sampling point in the first long training sequence codeword;

[0055] dd(j+DD) represents the data of the jth sampling point in the second long training sequence codeword. The second long training sequence codeword can also be understood as the codeword separated from the first long training sequence codeword by the number of long codeword sampling points DD;

[0056] conj() stands for conjugate operation;

[0057] arctan() represents the angle operation.

[0058] Preferably, in step 3, the data field constructs a channel coefficient subset of the pilot subcarriers to perform fine frequency offset estimation.

[0059] Preferably, in step 3, the data field constructs a channel coefficient subset of the pilot subcarrier in the frequency domain to perform fine frequency offset estimation.

[0060] Preferably, in step 3, the data field constructs a channel coefficient subset of pilot subcarriers in the frequency domain for fine frequency offset estimation, including: calculating the channel coefficients of P pilot subcarriers in the frequency domain of each data symbol of the data field, the channel coefficients of the pilot subcarriers of all symbols of the data field in the frequency domain constitute a pilot channel coefficient set H of the data field, and from the pilot channel coefficient set, respectively select an H1 subset and an H2 subset with M coefficients, and use these two subsets to perform fine frequency offset estimation.

[0061] Preferably, the following formula is used to calculate the fine frequency offset estimate:

[0062]

[0063] in,

[0064] Fs represents the sampling rate, in Hz. If the sampling rate is 20M, then F S =20e 6 ;

[0065] Ncp represents the number of sampling points of the guard interval GI of each data symbol in the data field in the time domain, N cp =GI×F S , where the data symbol guard interval GI is one of the three configurations of 0.8us, 1.6us, and 3.2us;

[0066] Nfft represents the number of sampling points of each valid data symbol in the data field in the time domain, N fft =SYM×F S , where the effective data symbol SYM of each data symbol in the time domain is fixed to 12.8us;

[0067] M represents the number of coefficients selected from the pilot channel coefficient set, and the value of M is P×(Num-1); wherein Num represents the number of data symbols contained in the data field, and P represents the number of pilot subcarriers in the frequency domain of each data symbol;

[0068] H1 represents subset 1, which indicates the subset selected from the first coefficient of the pilot channel coefficient set H;

[0069] H2 represents subset 2, which indicates a subset selected from the P+1th coefficient of the pilot channel coefficient set H;

[0070] j represents the index of the coefficient number in the subset;

[0071] H represents the channel coefficients of the frequency domain pilot subcarriers of all symbols of the data field, which constitute the pilot channel coefficient set of the data field; the formula for obtaining the j-th subcarrier channel coefficient in the pilot channel coefficient set is: Y j Represents the received signal of the jth subcarrier in the frequency domain, REF j Represents the known reference signal of the j-th subcarrier in the frequency domain.

[0072] Preferably, fine frequency offset compensation is performed on the signal after coarse frequency offset compensation in the time domain, and the fine frequency offset compensation formula is as follows:

[0073]

[0074] Where x1(t) is the signal after coarse frequency offset compensation, x2(t) is the received signal after fine frequency offset compensation, and f data is the fine frequency offset estimate, and t is the time sequence number.

[0075] The present invention also provides a frequency offset estimation system for a WIFI6 system, comprising a processor, which executes the above-mentioned frequency offset estimation method for a WIFI6 system.

[0076] Compared with the prior art, the beneficial effects of the present invention are:

[0077] 1. The present invention uses a short training sequence to construct a new sequence in the time domain whose length is much larger than the symbol length of the short training sequence for coarse frequency offset estimation. The coarse frequency offset estimation value is obtained by only one angle calculation, and no averaging operation is required. Compared with the prior art, the estimation accuracy and estimation speed are significantly improved on the basis of the unchanged frequency offset estimation range.

[0078] 2. The present invention estimates and compensates for the residual phase deviation of each data symbol in the frequency domain, and uses the compensated signal for subsequent demodulation, which can improve the performance of subsequent demodulation of the receiver. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 This is a flow chart of a frequency offset estimation method for a WIFI6 system according to an embodiment of the present invention;

[0080] Figure 2 A flow chart of a frequency offset estimation method for a WIFI6 system according to another embodiment of the present invention;

[0081] Figure 3 A flow chart of a frequency offset estimation method for a WIFI6 system according to another embodiment of the present invention;

[0082] Figure 4 This is a flow chart of a frequency offset estimation method for a WIFI6 system according to another embodiment of the present invention. DETAILED DESCRIPTION

[0083] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0084] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0085] Step 1, constructing a new sequence with a length greater than or equal to a preset length L based on the short training sequence, and performing coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value; so that the length of the new sequence is much greater than the symbol length of the short training sequence;

[0086] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0087] Step 3, perform fine frequency offset estimation;

[0088] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0089] In some specific embodiments of the present invention, in step 1, a new sequence with a length of L is constructed in the time domain based on the short training sequence to perform coarse frequency offset estimation.

[0090] In some specific embodiments of the present invention, in step 1, two adjacent repeated new sequence segments with lengths greater than or equal to a preset length L are constructed in the time domain based on the short training sequence, and a coarse frequency offset estimation value is obtained by calculating the angle.

[0091] In some specific embodiments of the present invention, in step 1, in the short training sequence LSTF sequence, the length of the new sequence is determined according to the number of sampling points D of the short codewords.

[0092] In some specific embodiments of the present invention, two repeated new sequence segments with a length of L=9D are selected, and the interval between the two new sequence segments is ensured to be the length of a short code element.

[0093] In some specific embodiments of the present invention, the coarse frequency offset estimation is calculated using the following formula:

[0094]

[0095] in,

[0096] f sts is the coarse frequency offset estimate;

[0097] Fs represents the sampling rate; if the sampling rate is 20M, then F S =20e 6 ;

[0098] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0099] n represents the index of the number of sampling points in the selected sequence segment;

[0100] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0101] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0102] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0103] conj() stands for conjugate operation;

[0104] arctan() represents the angle operation.

[0105] In some specific embodiments of the present invention, step 5 is further included after step 4, performing residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0106] In some specific embodiments of the present invention, in step 5, a residual phase deviation estimation value of each symbol is obtained in the frequency domain based on a received signal on a pilot subcarrier of each symbol and a known reference signal.

[0107] In some specific embodiments of the present invention, the residual phase deviation estimate of the lth symbol is calculated using the following formula:

[0108]

[0109] in,

[0110] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0111] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0112] l is the index of the data symbol of the data field;

[0113] Y l(k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0114] REF l (k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0115] φ l represents the residual phase deviation estimated for the lth data symbol.

[0116] In some specific embodiments of the present invention, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0117]

[0118] in,

[0119] k is the index of the subcarrier in the frequency domain of each data symbol;

[0120] l is the index of each data symbol in the data field;

[0121] φ l represents the estimated residual phase deviation of the lth data symbol;

[0122] Y l (k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0123] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0124] In some specific embodiments of the present invention, in step 3, a long training sequence LLTF is used to perform fine frequency offset estimation.

[0125] In some specific embodiments of the present invention, in step 3, a long training sequence LLTF is used, and a fine frequency offset estimation value is obtained by calculating the angle using long code elements of two adjacent long training sequences in the time domain.

[0126] In some specific embodiments of the present invention, in step 3, a long training sequence LLTF is used, and a fine frequency offset estimation value is obtained by calculating the angle using the long code elements of two adjacent repeated long training sequences in the time domain. The fine frequency offset estimation is specifically calculated using the following formula:

[0127]

[0128] in

[0129] f lts is the fine frequency deviation estimate;

[0130] Fs represents the sampling rate, in Hz; if the sampling rate is 20M, then F S =20e 6 ;

[0131] DD represents the number of sampling points of the long training sequence codeword, DD = 3.2 × 1e -6× F S ;

[0132] j represents the index of the sampling point number in the long training sequence codeword;

[0133] dd(j) represents the data of the jth sampling point in the first long training sequence codeword;

[0134] dd(j+DD) represents the data of the jth sampling point in the second long training sequence codeword. The second long training sequence codeword can also be understood as the codeword separated from the first long training sequence codeword by the number of long codeword sampling points DD;

[0135] conj() represents the conjugate operation;

[0136] arctan() represents the angle operation.

[0137] In some specific embodiments of the present invention, the data field constructs a channel coefficient subset of the pilot subcarriers for fine frequency offset estimation.

[0138] In some specific embodiments of the present invention, the data field constructs a channel coefficient subset of the pilot subcarrier in the frequency domain to perform fine frequency offset estimation.

[0139] In certain specific embodiments of the present invention, constructing a channel coefficient subset of pilot subcarriers in the frequency domain for the data field to perform fine frequency offset estimation includes: calculating the channel coefficients of P pilot subcarriers in the frequency domain for each data symbol of the data field, the channel coefficients of the pilot subcarriers of all symbols of the data field in the frequency domain constitute a pilot channel coefficient set H for the data field, and selecting an H1 subset and an H2 subset with M coefficients from the pilot channel coefficient set, and using these two subsets to perform fine frequency offset estimation.

[0140] In some specific embodiments of the present invention, the following formula is used to calculate the fine frequency offset estimate:

[0141]

[0142] in,

[0143] Fs represents the sampling rate. If the sampling rate is 20M, then F S =20e6 ;

[0144] Ncp represents the number of sampling points of the guard interval GI of each data symbol in the data field in the time domain, N cp =GI×F S , where the data symbol guard interval GI is one of the three configurations of 0.8us, 1.6us, and 3.2us;

[0145] Nfft represents the number of sampling points of each valid data symbol in the data field in the time domain, N fft =SYM×F S , where the effective data symbol SYM of each data symbol in the time domain is fixed to 12.8us;

[0146] M represents the number of coefficients selected from the pilot channel coefficient set, and the value of M is P×(Num-1); wherein Num represents the number of data symbols contained in the data field, and P represents the number of pilot subcarriers in the frequency domain of each data symbol;

[0147] H1 represents subset 1, which indicates the subset selected from the first coefficient of the pilot channel coefficient set H;

[0148] H2 represents subset 2, which indicates a subset selected from the P+1th coefficient of the pilot channel coefficient set H;

[0149] j represents the index of the coefficient number in the subset;

[0150] H represents the channel coefficients of the frequency domain pilot subcarriers of all symbols of the data field, which constitute the pilot channel coefficient set of the data field; the formula for obtaining the j-th subcarrier channel coefficient in the pilot channel coefficient set is: Y j Represents the received signal of the jth subcarrier in the frequency domain, REF j Represents a known reference signal of the j-th subcarrier in the frequency domain;

[0151] In some specific embodiments of the present invention, fine frequency offset compensation is performed on the signal after coarse frequency offset compensation in the time domain, and the fine frequency offset compensation formula is as follows:

[0152]

[0153] Where x1(t) is the signal after coarse frequency offset compensation, x2(t) is the received signal after fine frequency offset compensation, and f data is the fine frequency offset estimate, and t is the time sequence number.

[0154] The present invention also provides a frequency deviation estimation system for a WIFI6 system, comprising a processor, and the processor implements the above-mentioned frequency deviation estimation method for a WIFI6 system.

[0155] Example 1

[0156] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0157] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0158] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0159] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0160] Step 3, perform fine frequency offset estimation;

[0161] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0162] Example 2

[0163] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0164] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0165] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0166] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0167] Step 3, perform fine frequency offset estimation;

[0168] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0169] Based on the short training sequence, two adjacent repeated new sequence segments whose lengths are both greater than or equal to a preset length L are constructed in the time domain, and a coarse frequency offset estimation value is obtained by calculating the angle.

[0170] Example 3

[0171] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0172] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0173] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0174] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0175] Step 3, perform fine frequency offset estimation;

[0176] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0177] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D are constructed in the time domain, and the interval between the two new sequence segments is guaranteed to be the length of the short code element. The coarse frequency offset estimation value is obtained by calculating the angle, and D is the number of sampling points of the short code element.

[0178] Example 4

[0179] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0180] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0181] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0182] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0183] Step 3, perform fine frequency offset estimation;

[0184] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0185] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D are constructed in the time domain, and the interval between the two new sequence segments is ensured to be the length of the short code element, and the coarse frequency offset estimation value is calculated by the following formula:

[0186]

[0187] in,

[0188] f stsis the coarse frequency offset estimate;

[0189] Fs represents the sampling rate;

[0190] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0191] n represents the index of the number of sampling points in the selected sequence segment;

[0192] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0193] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0194] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0195] conj() represents the conjugate operation;

[0196] arctan() represents the angle operation.

[0197] Example 5

[0198] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0199] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0200] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0201] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0202] Step 3, perform fine frequency offset estimation;

[0203] Step 4, based on the fine frequency offset estimation, performing fine frequency offset compensation on the signal after the coarse frequency offset compensation;

[0204] Step 5: perform residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0205] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D are constructed in the time domain, and the interval between the two new sequence segments is ensured to be the length of the short code element, and the coarse frequency offset estimation value is calculated by the following formula:

[0206]

[0207] in,

[0208] f sts is the coarse frequency offset estimate;

[0209] Fs represents the sampling rate;

[0210] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0211] n represents the index of the number of sampling points in the selected sequence segment;

[0212] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0213] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0214] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0215] conj() represents the conjugate operation;

[0216] arctan() represents the angle operation.

[0217] In step 5, the residual phase deviation estimation value of the lth symbol is calculated in the frequency domain according to the received signal on each symbol pilot subcarrier and the known reference signal using the following formula:

[0218]

[0219] in,

[0220] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0221] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0222] l is the index of the data symbol of the data field;

[0223] Y l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0224] REF l(k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0225] φ l represents the residual phase deviation estimated for the lth data symbol.

[0226] In step 5, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0227]

[0228] in,

[0229] k is the index of the subcarrier in the frequency domain of each data symbol;

[0230] l is the index of each data symbol in the data field;

[0231] φ l represents the estimated residual phase deviation of the lth data symbol;

[0232] Y l (k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0233] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0234] Example 6

[0235] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0236] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0237] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0238] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0239] Step 3, use the long training sequence LLTF to perform fine frequency offset estimation;

[0240] Step 4: Based on the fine frequency offset estimation, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0241] Example 7

[0242] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0243] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0244] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0245] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0246] Step 3, use the long training sequence LLTF to perform fine frequency offset estimation;

[0247] Step 4, based on the fine frequency offset estimation, performing fine frequency offset compensation on the signal after the coarse frequency offset compensation;

[0248] Step 5: perform residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0249] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D are constructed in the time domain, and the interval between the two new sequence segments is ensured to be the length of the short code element, and the coarse frequency offset estimation value is calculated by the following formula:

[0250]

[0251] in,

[0252] f sts is the coarse frequency offset estimate;

[0253] Fs represents the sampling rate;

[0254] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0255] n represents the index of the number of sampling points in the selected sequence segment;

[0256] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0257] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0258] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0259] conj() represents the conjugate operation;

[0260] arctan() represents the angle operation.

[0261] In step 5, the residual phase deviation estimation value of the lth symbol is calculated in the frequency domain according to the received signal on each symbol pilot subcarrier and the known reference signal using the following formula:

[0262]

[0263] in,

[0264] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0265] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0266] l is the index of the data symbol of the data field;

[0267] Y l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0268] REF l (k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0269] φ l represents the residual phase deviation estimated for the lth data symbol.

[0270] In step 5, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0271]

[0272] in,

[0273] k is the index of the subcarrier in the frequency domain of each data symbol;

[0274] l is the index of each data symbol in the data field;

[0275] φ l represents the estimated residual phase deviation of the lth data symbol;

[0276] Y l(k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0277] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0278] Example 8

[0279] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0280] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0281] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0282] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0283] Step 3, using the long training sequence LLTF, using the long code elements of two adjacent long training sequences in the time domain to obtain a fine frequency offset estimate by calculating the angle;

[0284] Step 4, based on the fine frequency offset estimation, performing fine frequency offset compensation on the signal after the coarse frequency offset compensation;

[0285] Step 5: perform residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0286] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D and a resolution higher than the preamble code are constructed in the time domain, and the interval between the two new sequence segments is ensured to be the length of the short code element. The coarse frequency offset estimation value is calculated by the following formula:

[0287]

[0288] in,

[0289] f sts is the coarse frequency offset estimate;

[0290] Fs represents the sampling rate;

[0291] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0292] n represents the index of the number of sampling points in the selected sequence segment;

[0293] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0294] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0295] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0296] conj() represents the conjugate operation;

[0297] arctan() represents the angle operation.

[0298] In step 5, the residual phase deviation estimation value of the lth symbol is calculated in the frequency domain according to the received signal on each symbol pilot subcarrier and the known reference signal using the following formula:

[0299]

[0300] in,

[0301] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0302] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0303] l is the index of the data symbol of the data field;

[0304] Y l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0305] REF l (k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0306] φ l represents the residual phase deviation estimated for the lth data symbol.

[0307] In step 5, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0308]

[0309] in,

[0310] k is the index of the subcarrier in the frequency domain of each data symbol;

[0311] l is the index of each data symbol in the data field;

[0312] φ l represents the estimated residual phase deviation of the lth data symbol;

[0313] Y l (k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0314] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0315] In step 3, a long training sequence LLTF is used, and a fine frequency offset estimation value is obtained by calculating the angle using the long code elements of two adjacent repeated long training sequences in the time domain. The fine frequency offset estimation is specifically calculated using the following formula:

[0316]

[0317] in

[0318] f lts is the fine frequency deviation estimate;

[0319] Fs represents the sampling rate, in Hz; if the sampling rate is 20M, then F S =20e 6 ;

[0320] DD represents the number of sampling points of the long training sequence codeword, DD = 3.2 × 1e -6 ×F S ;

[0321] j represents the index of the sampling point number in the long training sequence codeword;

[0322] dd(j) represents the data of the jth sampling point in the first long training sequence codeword;

[0323] dd(j+DD) represents the data of the jth sampling point in the second long training sequence codeword. The second long training sequence codeword can also be understood as the codeword separated from the first long training sequence codeword by the number of long codeword sampling points DD;

[0324] conj() stands for conjugate operation;

[0325] arctan() represents the angle operation.

[0326] Example 9

[0327] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0328] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0329] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0330] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0331] Step 3: The data field constructs a channel coefficient subset of the pilot subcarrier to perform fine frequency offset estimation;

[0332] Step 4: Based on the fine frequency offset estimation value, perform fine frequency offset compensation on the signal after the coarse frequency offset compensation.

[0333] Example 10

[0334] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0335] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0336] Step 1: construct a new sequence with a length greater than or equal to a preset length L based on a short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0337] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0338] Step 3: The data field constructs a channel coefficient subset of the pilot subcarrier to perform fine frequency offset estimation;

[0339] Step 4, performing fine frequency offset compensation on the signal after coarse frequency offset compensation based on the fine frequency offset estimation value;

[0340] Step 5: perform residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0341] Embodiment 11

[0342] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0343] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0344] Step 1, constructing a new sequence with a length greater than or equal to a preset length L based on the short training sequence, and performing a coarse frequency offset estimation based on the constructed new sequence;

[0345] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0346] Step 3: The data field constructs a channel coefficient subset of the pilot subcarrier to perform fine frequency offset estimation;

[0347] Step 4, performing fine frequency offset compensation on the signal after coarse frequency offset compensation based on the fine frequency offset estimation value;

[0348] Step 5: perform residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0349] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D are constructed in the time domain, and the interval between the two new sequence segments is ensured to be the length of the short code element, and the coarse frequency offset estimation value is calculated by the following formula:

[0350]

[0351] in,

[0352] f sts is the coarse frequency offset estimate;

[0353] Fs represents the sampling rate;

[0354] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0355] n represents the index of the number of sampling points in the selected sequence segment;

[0356] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0357] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0358] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0359] conj() represents the conjugate operation;

[0360] arctan() represents the angle operation.

[0361] In step 5, the residual phase deviation estimation value of the lth symbol is calculated in the frequency domain according to the received signal on each symbol pilot subcarrier and the known reference signal using the following formula:

[0362]

[0363] in,

[0364] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0365] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0366] l is the index of the data symbol of the data field;

[0367] Y l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0368] REF l (k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0369] φ l represents the residual phase deviation estimated for the lth data symbol.

[0370] In step 5, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0371]

[0372] in,

[0373] k is the index of the subcarrier in the frequency domain of each data symbol;

[0374] l is the index of each data symbol in the data field;

[0375] φ l represents the estimated residual phase deviation of the lth data symbol;

[0376] Y l (k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0377] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0378] Among them, in step 3, the data field constructs a channel coefficient subset of the pilot subcarrier in the frequency domain for fine frequency offset estimation, including: calculating the channel coefficients of P pilot subcarriers in the frequency domain of each data symbol of the data field, the channel coefficients of the pilot subcarriers of all symbols of the data field in the frequency domain constitute the pilot channel coefficient set H of the data field, and the H1 subset and H2 subset with M coefficients are selected from the pilot channel coefficient set, and these two subsets are used to perform fine frequency offset estimation.

[0379] Example 12

[0380] According to a specific implementation scheme of the present invention, the frequency offset estimation method for a WIFI6 system of the present invention is described in detail below.

[0381] The present invention provides a frequency deviation estimation method for a WIFI6 system, comprising the following steps:

[0382] Step 1: construct a new sequence with a length greater than or equal to a preset length L and a resolution higher than the preamble code based on the short training sequence, and perform a coarse frequency offset estimation based on the constructed new sequence; the difference between L and the symbol length of the short training sequence is greater than a preset threshold value;

[0383] Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal;

[0384] Step 3: The data field constructs a channel coefficient subset of the pilot subcarrier to perform fine frequency offset estimation;

[0385] Step 4, performing fine frequency offset compensation on the signal after coarse frequency offset compensation based on the fine frequency offset estimation value;

[0386] Step 5: perform residual phase deviation estimation and compensation on each data symbol in the frequency domain.

[0387] Among them, based on the short training sequence LSTF sequence, two adjacent repeated new sequence segments with a length of L=9D are constructed in the time domain, and the interval between the two new sequence segments is ensured to be the length of the short code element, and the coarse frequency offset estimation value is calculated by the following formula:

[0388]

[0389] in,

[0390] f sts is the coarse frequency offset estimate;

[0391] Fs represents the sampling rate;

[0392] D represents the number of sampling points of the short code element, D = 0.8 × 1e -6 ×F S ;

[0393] n represents the index of the number of sampling points in the selected sequence segment;

[0394] s(n) represents the data of the nth sampling point in the first new sequence segment constructed;

[0395] s(n+D) represents the data of the nth sampling point in the constructed second new sequence segment. The second new sequence segment can also be understood as a sequence segment separated from the first new sequence segment by the number of short code element sampling points D;

[0396] L is the length of the sampling points for constructing a new sequence segment, and L=9D;

[0397] conj() represents the conjugate operation;

[0398] arctan() represents the angle operation.

[0399] In step 5, the residual phase deviation estimation value of the lth symbol is calculated in the frequency domain according to the received signal on each symbol pilot subcarrier and the known reference signal using the following formula:

[0400]

[0401] in,

[0402] k is the index of the pilot subcarrier of the current data symbol in the frequency domain;

[0403] P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain;

[0404] l is the index of the data symbol of the data field;

[0405] Y l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after fine frequency offset compensation;

[0406] REF l (k) represents a known reference signal of the lth data symbol on the frequency domain subcarrier, and its corresponding position is the kth pilot subcarrier on the frequency domain of the lth data symbol;

[0407] φ l represents the residual phase deviation estimated for the lth data symbol.

[0408] In step 5, each data symbol is compensated for residual phase deviation in the frequency domain using the following formula:

[0409]

[0410] in,

[0411] k is the index of the subcarrier in the frequency domain of each data symbol;

[0412] l is the index of each data symbol in the data field;

[0413] φ l represents the estimated residual phase deviation of the lth data symbol;

[0414] Y l (k) indicates that the signal of the lth data symbol after fine frequency offset compensation is received on the frequency domain subcarrier, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol;

[0415] Y 1,l (k) represents the received signal of the lth data symbol on the frequency domain subcarrier after residual phase deviation compensation, and its corresponding position is the kth subcarrier on the frequency domain of the lth data symbol.

[0416] Among them, in step 3, the data field constructs a channel coefficient subset of the pilot subcarrier in the frequency domain for fine frequency offset estimation, including: calculating the channel coefficients of P pilot subcarriers in the frequency domain of each data symbol of the data field, the channel coefficients of the pilot subcarriers of all symbols of the data field in the frequency domain constitute the pilot channel coefficient set H of the data field, and the H1 subset and H2 subset with M coefficients are selected from the pilot channel coefficient set, and these two subsets are used to perform fine frequency offset estimation.

[0417] The fine frequency offset estimate is calculated using the following formula:

[0418]

[0419] in,

[0420] Fs represents the sampling rate. If the sampling rate is 20M, then F S =20e 6 ;

[0421] Ncp represents the number of sampling points of the guard interval GI of each data symbol in the data field in the time domain, N cp =GI×F S , where the data symbol guard interval GI is one of the three configurations of 0.8us, 1.6us, and 3.2us;

[0422] Nfft represents the number of sampling points of each valid data symbol in the data field in the time domain, N fft =SYM×F S , where the effective data symbol SYM of each data symbol in the time domain is fixed to 12.8us;

[0423] M represents the number of coefficients selected from the pilot channel coefficient set, and the value of M is P×(Num-1); wherein Num represents the number of data symbols contained in the data field, and P represents the number of pilot subcarriers in the frequency domain of each data symbol;

[0424] H1 represents subset 1, which indicates the subset selected from the first coefficient of the pilot channel coefficient set H;

[0425] H2 represents subset 2, which indicates a subset selected from the P+1th coefficient of the pilot channel coefficient set H;

[0426] j represents the index of the coefficient number in the subset;

[0427] H represents the channel coefficients of the frequency domain pilot subcarriers of all symbols of the data field, which constitute the pilot channel coefficient set of the data field; the formula for obtaining the j-th subcarrier channel coefficient in the pilot channel coefficient set is: Y j Represents the received signal of the jth subcarrier in the frequency domain, REF j Represents a known reference signal of the j-th subcarrier in the frequency domain;

[0428] In the time domain, fine frequency offset compensation is performed on the signal after coarse frequency offset compensation. The fine frequency offset compensation formula is as follows:

[0429]

[0430] Where x1(t) is the signal after coarse frequency offset compensation, x2(t) is the received signal after fine frequency offset compensation, and f data is the fine frequency offset estimate, and t is the time sequence number.

[0431] Example 13

[0432] According to a specific implementation scheme of the present invention, the frequency offset estimation system for the WIFI6 system of the present invention is described in detail below.

[0433] The present invention also provides a frequency offset estimation system for a WIFI6 system, comprising a processor, which executes the above-mentioned frequency offset estimation method for a WIFI6 system.

[0434] 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 are included in the protection scope of the present invention.

Claims

1. A frequency deviation estimation method for a WIFI6 system, characterized in that: The steps include: Step 1: construct two adjacent new repeated sequences in the time domain based on the short training sequence, both of which have lengths greater than or equal to a preset length L, select two new repeated sequence segments with a length of L=9D, and ensure that the interval between the two new sequence segments is the length of a short codeword, perform a coarse frequency offset estimation based on the constructed new sequence, and obtain a coarse frequency offset estimation value by calculating the angle; the difference between L and the short training sequence codeword length is greater than a preset threshold value; In the short training sequence LSTF sequence, the length of the new sequence is determined according to the number of sampling points D of the short codeword; Step 2, based on the coarse frequency offset estimation, performing coarse frequency offset compensation on the received signal; Step 3, perform fine frequency offset estimation; Step 4, based on the fine frequency offset estimation, performing fine frequency offset compensation on the signal after the coarse frequency offset compensation; The coarse frequency offset estimation is calculated using the following formula: ； in, is the coarse frequency offset estimate; F Represents the sampling rate in Hz; D Represents the number of sampling points of the short codeword, ; n The index representing the number of sampling points in the selected sequence segment; s ( n ) represents the data of the nth sampling point in the first new sequence segment constructed; s ( n + D ) represents the data of the nth sampling point in the second new sequence segment constructed; L To construct the length of the sampling points of the new sequence segment, take L=9D; conj () represents the conjugate operation; arctan () represents the angle operation.

2. The frequency deviation estimation method for a WIFI6 system according to claim 1, characterized in that: After step 4, the method further includes step 5, which estimates and compensates the residual phase deviation of each data symbol in the frequency domain.

3. The frequency deviation estimation method for a WIFI6 system according to claim 2, characterized in that: In step 5, the residual phase deviation estimation value of each symbol is calculated in the frequency domain based on the received signal on the pilot subcarrier of each symbol and the known reference signal.

4. The frequency deviation estimation method for a WIFI6 system according to claim 3, characterized in that: Use the following formula to calculate the l The residual phase deviation estimate for symbols is: in, k is the index of the pilot subcarrier of the current data symbol in the frequency domain; P is the total number of pilot subcarriers contained in the current data symbol in the frequency domain; is the index of the data symbol of the data field; Indicates the first The received signal of data symbols on the frequency domain subcarriers; Indicates The corresponding position of the known reference signal of the data symbol on the frequency domain subcarrier is The frequency domain of the data symbol k pilot subcarriers; Indicates The residual phase deviation estimated for each data symbol.

5. The frequency deviation estimation method for a WIFI6 system according to claim 3, characterized in that: Each data symbol is compensated for residual phase deviation in the frequency domain using the following formula: in, k is the index of the subcarrier in the frequency domain for each data symbol; is the index of each data symbol of the data field; Indicates The residual phase deviation estimated for each data symbol; Indicates the first The data symbol receives the signal on the frequency domain subcarrier, and its corresponding position is The frequency domain of the data symbol k subcarriers; Residual phase deviation after compensation The received signal of the data symbol on the frequency domain subcarrier corresponds to the position of The frequency domain of the data symbol k subcarriers.

6. A frequency deviation estimation system for a WIFI6 system, characterized in that: It includes a processor, which executes the frequency offset estimation method for a WIFI6 system as described in any one of claims 1-5.

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