High-precision time-frequency synchronization system, method and device of spread spectrum leader sequence

Abstract

The invention discloses a high-precision time-frequency synchronization system, method and device for a spread spectrum leader sequence, and belongs to the field of wireless communication, and the system comprises an integral reduction and acquisition module, a storage and reading control module, a first-stage decorrelation module, a second-stage decorrelation module and a detection and calculation module. The integral reduced acquisition module carries out integral reduced acquisition processing on the received signal, and the storage and reading control module adopts a reduced acquisition data cycle asynchronous storage and reading processing architecture to realize real-time parallelism of signal reduced acquisition and data processing; the first-stage decorrelation module adopts matched filtering and coherent integration to carry out parallel phase despreading of spread spectrum pseudo codes, and the second-stage decorrelation module adopts sliding correlation and zero-fill FFT to carry out information demodulation of a leader sequence; and the detection resolving module realizes high-precision time-frequency synchronization of the spread spectrum leader sequence by adopting integral peak self-adaptive detection in combination with least square fitting. The method has the advantages of high time-frequency synchronization precision, high receiving sensitivity and large dynamic application range, and the time-frequency synchronization precision and the receiving sensitivity of the spread spectrum communication system can be improved.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications, and more specifically, to a high-precision time-frequency synchronization system, method and device for a spread spectrum preamble sequence. Background Art

[0002] Compared with narrowband communication, spread spectrum communication has the advantages of high spectrum utilization, strong anti-interference, anti-multipath interference, and the ability to implement code division multiple access. It is widely used in the field of modern wireless communications. Based on spread spectrum signals, burst spread spectrum signals have a short duration and are transmitted covertly, requiring the receiving end to complete the time and frequency synchronization of the burst signal in a relatively short time.

[0003] The information modulated by the spread spectrum burst signal consists of three parts in the order of transmission: the preamble sequence, the frame header sequence, and the data sequence. The preamble sequence is usually a known symbol used to perform time-frequency synchronization and channel estimation at the receiving end. The frame header sequence is used to determine the starting position of the valid data and frame synchronization. The data sequence is valid information data and transmits information according to the design file. Therefore, the high-precision time-frequency synchronization of the preamble sequence at the receiving end in the spread spectrum communication system is an important prerequisite and reliable guarantee for signal despreading and recovery of the transmitted information data.

[0004] The preamble sequence can be meaningless as a known symbol, but through certain signal processing methods, the preamble sequence can carry special control information or system information. Expanding the function of the preamble sequence in the communication system can improve the system's frequency band utilization and enhance the system's effectiveness. For example, the information carried in the preamble sequence can be used to represent the sender's special identification for encryption, carry digital signature information for identity authentication, etc.

[0005] Since the relative motion between the transmitter and the receiver will produce the Doppler effect, the signal received by the receiver has a large Doppler frequency shift, and when there is acceleration and deceleration in the radial motion between them, the received signal has a Doppler change rate and a high-order change rate, which is not conducive to signal synchronization detection. When the burst signal occupies a small power of the transmitter, the burst signal is less likely to be detected and has a strong ability to resist reconnaissance and interception. However, at this time, the high dynamic characteristics of the signal have a more serious impact on signal synchronization, and the detection of the burst signal is more difficult. Therefore, the time-frequency synchronization method of the burst signal under high dynamic and low signal-to-noise ratio conditions is of great significance.

[0006] Traditional methods for time-frequency synchronization of spread spectrum preamble sequences are mainly divided into time domain detection algorithms and frequency domain detection algorithms. Time domain detection algorithms include short-time energy method, high-order cumulant method, etc. Frequency domain detection algorithms include discrete Fourier transform method, cyclic spectrum detection method, etc. Traditional methods usually use known preamble sequences and signal downsampling sequences for sliding correlation, then use zero padding method for high-resolution FFT, and finally obtain Doppler frequency through peak search. This method has large computational complexity, low frequency estimation accuracy, and poor real-time performance, and cannot meet the requirements for time-frequency synchronization accuracy of preamble sequences in spread spectrum communication systems under high dynamic and low signal-to-noise ratio conditions. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a high-precision time-frequency synchronization system, method and device for a spread spectrum preamble sequence, which has the advantages of high time-frequency synchronization accuracy, high receiving sensitivity and a large dynamic adaptation range, and can achieve high-precision time-frequency synchronization of the preamble sequence of the spread spectrum communication system under high dynamic and low signal-to-noise ratio conditions, and significantly improve the time-frequency synchronization accuracy and receiving sensitivity of the spread spectrum communication system.

[0008] The object of the present invention is achieved through the following solutions:

[0009] A high-precision time-frequency synchronization system for a spread spectrum preamble sequence, comprising:

[0010] Integral downsampling module, storage and reading control module, first level decorrelation module, second level decorrelation module and detection and solution module;

[0011] The integration and downsampling module performs integration and downsampling processing on the received signal. The storage and reading control module adopts the downsampling data cycle asynchronous storage and reading processing architecture to realize the real-time parallel of signal downsampling and data processing. The first-level decorrelation module adopts matched filtering and coherent integration to perform parallel phase demodulation of spread spectrum pseudocode. The second-level decorrelation module adopts sliding correlation and zero-filled FFT to demodulate the information of the leading sequence. The detection and solution module compares and judges the integral peak with the adaptive detection threshold, and adopts least squares fitting to perform high-precision time-frequency synchronization of the spread spectrum leading sequence.

[0012] Furthermore, the integration and reduction module performs integration and reduction processing on the received signal, specifically including:

[0013] The frequency f of the integrated downsampling module s For LR s , using the calculation formula CW s =f s ×2 32 / f ad Perform data conversion, where L is an integer multiple of downsampling, R s is the spread spectrum pseudo code rate, f adThe frequency of the received signal data is obtained by integrating the downsampled frequency control word CW s , a clear pulse is generated by a direct digital frequency synthesizer DDS; then an accumulator is used to continuously coherently accumulate the received signal, and when the clear pulse is valid, the down-sampled data and the enable pulse are output, and the accumulator is cleared.

[0014] Furthermore, the storage and reading control module adopts a downsampling data cycle asynchronous storage and reading processing architecture to realize real-time parallelization of signal downsampling and data processing, specifically including:

[0015] When the enable pulse is valid, the storage and reading control module stores and writes the downsampled data to the data cache module, and the storage and writing address A wr From 0 to A max , when writing address A wr A max When writing address A wr Initialization starts from 0; control count cnt wr When the enable pulse is valid, it increases from 0 to cnt max , when the control count cnt wr When LN, control count cnt wr Initialized to 0, and generates a read enable pulse e rd and read the initial address A ini , read the initial address A ini Satisfies the following relationship:

[0016]

[0017] Among them, A max is the maximum value of the data cache, N is the spread spectrum pseudo code period, and M is the preamble sequence period; when the read enable pulse e rd When valid, read address A rd From A ini Increase to A ini +LN×M-1, when A rd ≥A max When A is satisfied rd =A rd -A max , the LN×M downsampled data output by the data cache module are output to the first-level decorrelation module.

[0018] Furthermore, the first-level decorrelation module adopts matched filtering and coherent integration to perform parallel phase demodulation of the spread spectrum pseudocode, specifically including: the first-level decorrelation module uses matched filtering to perform parallel phase demodulation of the spread spectrum pseudocode on the LN×M down-sampled data output by the data buffer module in combination with the N spread spectrum pseudocodes output by the spread spectrum pseudocode module, performs LN point coherent integration to obtain LN×M demodulated data, and writes the LN×M demodulated data to the correlation buffer module in a row-first-column-later manner.

[0019] Furthermore, the second-level decorrelation module adopts sliding correlation and zero-padding FFT to demodulate the information of the leading sequence, specifically including: the second-level decorrelation module reads M×LN demodulated data from the correlation buffer module in a column-first-row-later manner, combines the M leading sequences output by the leading sequence module, and adopts a sliding correlation method to demodulate the information of the leading sequence on the M×LN demodulated data to obtain M×LN demodulated data; then, the M×LN demodulated data are zero-padding-operated to convert them into KM×LN data, and LN times of KM-point fast Fourier transform are performed to obtain KM×LN integrated data.

[0020] Furthermore, the detection and solution module uses the integrated peak to compare and determine with the adaptive detection threshold, specifically including: the detection and solution module uses a comparative search method to obtain the integrated peak V vpp , the corresponding frequency index / pseudocode index is k vpp / τ vpp ; Use weighted average method to get the integral mean V avg , combined with the detection threshold proportionality factor κ thr , get the adaptive detection threshold V thr κ thr ×V avg ; The integrated peak V vpp With adaptive detection threshold V thr Compare and judge, when V vpp >V thr , it indicates that the synchronization is successful, otherwise it fails.

[0021] Furthermore, the high-precision time-frequency synchronization of the spread spectrum preamble sequence using least square fitting specifically includes: when the detection solution module is successfully synchronized, at the integral peak frequency index k vpp Take K / 2 integral data and integral peak V on the left and right sides respectively vpp Get K+1 integral data, and bring K+1 integral data into the quadratic function V=ak 2 +bk+c, where a is the coefficient of the quadratic term, b is the coefficient of the linear term, and c is the coefficient of the constant term. The matrix equation is:

[0022] in, is the integrated data matrix, is the frequency index matrix, is the function parameter matrix, and the least quadratic method is used to solve the matrix equation V = F × D to obtain the least quadratic solution of the function parameters for in is the coefficient solution of the quadratic term, is the coefficient solution of the first-order term, is the constant term coefficient solution, then the detection solution obtains the sequence position for Carrier frequency for

[0023] Furthermore, it also includes a data cache module for caching relevant data.

[0024] A high-precision time-frequency synchronization method for a spread spectrum preamble sequence comprises the following steps:

[0025] S1, constructing a high-precision time-frequency synchronization system for a spread spectrum preamble sequence as described in any one of the above items;

[0026] S2, using the system constructed in step S1 for time-frequency synchronization of the preamble sequence of the spread spectrum communication system.

[0027] A high-precision time-frequency synchronization device for a spread spectrum preamble sequence comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is loaded by the processor, the method described above is executed.

[0028] The beneficial effects of the present invention include:

[0029] (1) High time-frequency synchronization accuracy. The present invention adopts a downsampling data cycle asynchronous storage and reading processing architecture to realize real-time parallel signal downsampling and data processing, which greatly reduces the timing error caused by large delays in the long-term downsampling data processing process; uses an integer multiple of the downsampling frequency to perform integrated downsampling processing on the received signal, which has a higher precision of the leading sequence timing position; uses a method combining zero-filled FFT with least squares fitting to further improve the measurement accuracy of the carrier frequency. Compared with traditional synchronization methods, the present invention can provide higher precision sequence position and carrier frequency.

[0030] (2) High receiving sensitivity. The present invention adopts a two-stage decorrelation integral processing architecture to realize the fully coherent integral processing of the entire spread spectrum preamble sequence, ensuring that there is no integral loss in the accumulation processing of the down-sampled data; the integral down-sampled frequency is used to perform integral down-sampled processing on the received signal, which weakens the gain loss caused by the initial phase ambiguity of the spread spectrum pseudo code; the zero-filled FFT method is used to perform time-frequency conversion on the demodulated data, eliminating the gain loss caused by the "fence effect" formed by spectrum leakage after the demodulated data is truncated. Compared with the traditional synchronization method, the present invention has a higher integral gain to achieve higher receiving sensitivity.

[0031] (3) Wide application scope. The present invention adopts the data downsampling cycle asynchronous storage and reading processing architecture to realize the real-time parallel of signal downsampling and data processing, which can meet the requirements of fast synchronization under short-term burst conditions; adopts the sliding correlation method to demodulate the information of the leading sequence of the demodulated data, which can meet the demodulation requirements of various modulation leading sequences; adopts the zero-filling FFT method to perform a large-point fast Fourier transform on the demodulated data, which can meet the requirements of high-precision measurement of a wide range of carrier frequencies under high dynamic conditions. Compared with the traditional synchronization method, the present invention has the application requirements in complex scenarios such as high dynamic, low signal-to-noise ratio, and short-term burst. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0033] Figure 1 A schematic diagram of the structural principle of the system according to an embodiment of the present invention;

[0034] Figure 2 for Figure 1 Schematic diagram of the structural principle of the integral downsampling module;

[0035] Figure 3 for Figure 1 Schematic diagram of the structural principle of the first-level decorrelation module in;

[0036] Figure 4 for Figure 1 Schematic diagram of the structural principle of the second-level decorrelation module in . DETAILED DESCRIPTION

[0037] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0038] The present invention aims to solve the problem of poor time-frequency synchronization accuracy of the leading sequence of a spread spectrum communication system under high dynamic and low signal-to-noise ratio conditions, and proposes a high-precision time-frequency synchronization system, method and device for the spread spectrum leading sequence.

[0039] In a specific embodiment, see Figure 1 . According to the present invention, in a first aspect, a high-precision time-frequency synchronization system for a spread spectrum preamble sequence is provided, the system comprising: an integration and downsampling module, a storage and reading control module, a data cache module, a first-level decorrelation module, a correlation buffer module, a second-level decorrelation module and a detection and solution module, the integration and downsampling module performs integration and downsampling processing on a received signal, the storage and reading control module adopts a downsampling data cycle asynchronous storage and reading processing architecture to realize real-time parallel signal downsampling and data processing, the first-level decorrelation module adopts matched filtering and coherent integration to perform parallel phase demodulation of a spread spectrum pseudocode, the second-level decorrelation module adopts sliding correlation and zero-filled FFT to demodulate the information of the preamble sequence, the detection and solution module adopts an integral peak and an adaptive detection threshold for comparison and judgment, and adopts least squares fitting to perform high-precision time-frequency synchronization of the spread spectrum preamble sequence.

[0040] In other specific embodiments, see Figure 2 On the basis of the above embodiment, the integration and reduction sampling module performs integration and reduction sampling processing on the received signal, and further, the reduction sampling frequency f of the integration and reduction sampling module is s For LR s , using the calculation formula CW s =f s ×2 32 / f ad Perform data conversion, where L is an integer multiple of downsampling, R s is the spread spectrum pseudo code rate, f ad The frequency of the received signal data is obtained by integrating the downsampled frequency control word CW s , a clear pulse is generated by a direct digital frequency synthesizer (DDS), and then an accumulator is used to continuously coherently accumulate the received signal. When the clear pulse is valid, the down-sampled data and enable pulse are output, and the accumulator is cleared.

[0041] In other specific embodiments, based on the above embodiments, the storage and reading control module adopts a downsampling data cycle asynchronous storage and reading processing architecture to realize real-time parallelization of signal downsampling and data processing. Further, the storage and reading control module writes the downsampling data to the data cache module when the enable pulse is valid, and the write address A wr From 0 to A max , when writing address A wr A max When writing address A wr Initialization starts from 0; control count cntwr When the enable pulse is valid, it increases from 0 to cnt max , when the control count cnt wr When LN, control count cnt wr Initialized to 0, and generates a read enable pulse e rd and read the initial address A ini , read the initial address A ini satisfy Among them, A max is the maximum value of the data cache, N is the spread spectrum pseudo code period, and M is the preamble sequence period; when the read enable pulse e rd When valid, read address A rd From A ini Increase to A ini +LN×M-1, when A rd ≥A max When A is satisfied rd =A rd -A max , the LN×M downsampled data output by the data cache module are output to the first-level decorrelation module.

[0042] In other specific embodiments, see Figure 3 On the basis of the above embodiment, the first-level decorrelation module adopts matched filtering and coherent integration to perform parallel phase despreading of the spread spectrum pseudo code. Further, the first-level decorrelation module uses matched filtering to perform parallel phase despreading of the spread spectrum pseudo code on the LN×M down-sampled data output by the data buffer module in combination with the N spread spectrum pseudo codes output by the spread spectrum pseudo code module, performs LN point coherent integration to obtain LN×M despread data, and writes the LN×M despread data to the correlation buffer module in a row-first-column-later manner.

[0043] In other specific embodiments, see Figure 4 . On the basis of the above embodiment, the second-level decorrelation module adopts sliding correlation and zero-filling FFT to demodulate the information of the leading sequence. Further, the second-level decorrelation module reads M×LN demodulated data from the correlation buffer module in a column-first-row-later manner, combines the M leading sequences output by the leading sequence module, and adopts a sliding correlation method to demodulate the information of the leading sequence on the M×LN demodulated data to obtain M×LN demodulated data; performs zero-filling operation on the M×LN demodulated data, converts them into KM×LN data, performs LN times of KM-point fast Fourier transform, and obtains KM×LN integrated data.

[0044] In other specific embodiments, based on the above embodiments, the detection and solution module uses the integral peak and the adaptive detection threshold for comparison and judgment. Further, the detection and solution module uses a comparison search method to obtain the integral peak V of the KM×LN integral data output by the second-level decorrelation module. vpp , the corresponding frequency index / pseudocode index is k vpp / τ vpp ; Use weighted average method to get the integral mean V avg , combined with the detection threshold proportionality factor κ thr , get the adaptive detection threshold V thr κ thr ×V avg ; The integrated peak V vpp With adaptive detection threshold V thr Compare and judge, when V vpp >V thr , it indicates that the synchronization is successful, otherwise it fails.

[0045] In other specific embodiments, based on the above embodiments, the detection and solution module uses least squares fitting to perform high-precision time-frequency synchronization of the spread spectrum preamble sequence. Further, when the detection and solution module is successfully synchronized, the integral peak frequency index k vpp Take K / 2 integral data and integral peak V on the left and right sides respectively vpp Get K+1 integral data, and bring K+1 integral data into the quadratic function V=ak 2 +bk+c, where a is the coefficient of the quadratic term, b is the coefficient of the linear term, and c is the coefficient of the constant term. The matrix equation is: in, is the integrated data matrix, is the frequency index matrix, is the function parameter matrix, and the least quadratic method is used to solve the matrix equation V = F × D to obtain the least quadratic solution of the function parameters for in is the coefficient solution of the quadratic term, is the coefficient solution of the first-order term, is the constant term coefficient solution, then the detection solution obtains the sequence position for Carrier frequency for

[0046] The units involved in the embodiments of the present invention may be implemented by software or hardware, and the units described may also be arranged in a processor. The names of these units do not, in some cases, limit the units themselves.

[0047] According to one aspect of an embodiment of the present invention, a computer program product or a computer program is provided, the computer program product or the computer program includes a computer instruction, and the computer instruction is stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the method provided in the above various optional implementations.

[0048] As another aspect, an embodiment of the present invention further provides a computer-readable medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above computer-readable medium carries one or more programs, and when the above one or more programs are executed by an electronic device, the electronic device implements the method described in the above embodiment.

Claims

1. A high-precision time-frequency synchronization system for a spread spectrum preamble sequence, characterized in that: include: Integral downsampling module, storage and reading control module, first level decorrelation module, second level decorrelation module and detection and solution module; The integration and downsampling module performs integration and downsampling processing on the received signal. The storage and reading control module adopts the downsampling data cycle asynchronous storage and reading processing architecture to realize the real-time parallel of signal downsampling and data processing. The first-level decorrelation module adopts matched filtering and coherent integration to perform parallel phase demodulation of spread spectrum pseudocode. The second-level decorrelation module adopts sliding correlation and zero-filled FFT to demodulate the information of the leading sequence. The detection and solution module compares and judges the integral peak with the adaptive detection threshold, and adopts least squares fitting to perform high-precision time-frequency synchronization of the spread spectrum leading sequence.

2. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 1, characterized in that: The integration and reduction module performs integration and reduction processing on the received signal, specifically including: The frequency f of the integrated downsampling module s For LR s , using the calculation formula CW s =f s ×2 32 / f ad Perform data conversion, where L is an integer multiple of downsampling, R s is the spread spectrum pseudo code rate, f ad The frequency of the received signal data is obtained by integrating the downsampled frequency control word CW s , a clear pulse is generated by a direct digital frequency synthesizer DDS; then an accumulator is used to continuously coherently accumulate the received signal, and when the clear pulse is valid, the down-sampled data and the enable pulse are output, and the accumulator is cleared.

3. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 2, characterized in that: The storage and reading control module adopts the downsampling data cycle asynchronous storage and reading processing architecture to realize the real-time parallel of signal downsampling and data processing, which specifically includes: When the enable pulse is valid, the storage and reading control module stores and writes the downsampled data to the data cache module, and the storage and writing address A wr From 0 to A max , when writing address A wr A max When writing address A wr Initialization starts from 0; control count cnt wr When the enable pulse is valid, it increases from 0 to cnt max , when the control count cnt wr When LN, control count cnt wr Initialized to 0, and generates a read enable pulse e rd and read the initial address A ini , read the initial address A ini Satisfies the following relationship: Among them, A max is the maximum value of the data cache, N is the spread spectrum pseudo code period, and M is the preamble sequence period; when the read enable pulse e rd When valid, read address A rd From A ini Increase to A ini +LN×M-1, when A rd ≥A max When A is satisfied rd =A rd -A max , the LN×M downsampled data output by the data cache module are output to the first-level decorrelation module.

4. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 1, characterized in that: The first-level decorrelation module uses matched filtering and coherent integration to perform parallel phase demodulation of the spread spectrum pseudo code, specifically including: the first-level decorrelation module uses matched filtering to perform parallel phase demodulation of the spread spectrum pseudo code on the LN×M down-sampled data output by the data buffer module in combination with the N spread spectrum pseudo codes output by the spread spectrum pseudo code module, performs LN point coherent integration to obtain LN×M demodulated data, and stores the LN×M demodulated data in the correlation buffer module in a row-first-column-later manner.

5. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 1, characterized in that: The second-level decorrelation module adopts sliding correlation and zero-padding FFT to demodulate the information of the leading sequence, specifically including: the second-level decorrelation module reads M×LN demodulated data from the correlation buffer module in a column-first-row-later manner, combines the M leading sequences output by the leading sequence module, and adopts a sliding correlation method to demodulate the information of the leading sequence on the M×LN demodulated data to obtain M×LN demodulated data; then, a zero-padding operation is performed on the M×LN demodulated data to convert them into KM×LN data, and LN times of KM-point fast Fourier transform are performed to obtain KM×LN integrated data.

6. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 5, characterized in that: The detection and solution module uses the integrated peak and the adaptive detection threshold for comparison and judgment, specifically including: the detection and solution module uses a comparison search method to obtain the integrated peak V vpp , the corresponding frequency index / pseudocode index is k vpp / τ vpp ; Use weighted average method to get the integral mean V avg , combined with the detection threshold proportionality factor κ thr , get the adaptive detection threshold V thr κ thr ×V avg ; The integrated peak V vpp With adaptive detection threshold V thr Compare and judge, when V vpp >V thr , it indicates that the synchronization is successful, otherwise it fails.

7. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 1, characterized in that: The method of using least square fitting to perform high-precision time-frequency synchronization of the spread spectrum preamble sequence specifically includes: when the detection and solution module is successfully synchronized, the integral peak frequency index k vpp Take K / 2 integral data and integral peak V on the left and right sides respectively vpp Get K+1 integral data, and bring K+1 integral data into the quadratic function V=ak 2 +bk+c, where a is the coefficient of the quadratic term, b is the coefficient of the linear term, and c is the coefficient of the constant term. The matrix equation is: in, is the integrated data matrix, is the frequency index matrix, is the function parameter matrix, and the least quadratic method is used to solve the matrix equation V = F × D to obtain the least quadratic solution of the function parameters for in is the coefficient solution of the quadratic term, is the coefficient solution of the first-order term, is the constant term coefficient solution, then the detection solution obtains the sequence position for Carrier frequency for 8. The high-precision time-frequency synchronization system of the spread spectrum preamble sequence according to claim 1, characterized in that: It also includes a data cache module for caching relevant data.

9. A high-precision time-frequency synchronization method for a spread spectrum preamble sequence, characterized in that: The following steps are involved: S1, constructing a high-precision time-frequency synchronization system for a spread spectrum preamble sequence as described in any one of claims 1 to 8; S2, using the system constructed in step S1 for time-frequency synchronization of the preamble sequence of the spread spectrum communication system.

10. A high-precision time-frequency synchronization device for a spread spectrum preamble sequence, characterized in that: The method comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is loaded by the processor, the method according to claim 9 is executed.

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