Space-frequency joint anti-interference signal receiving method suitable for TDMA (Time Division Multiple Access) network

Abstract

The invention discloses a space-frequency joint anti-interference signal receiving method suitable for a TDMA network, and relates to the technical field of ad hoc network transmission and wireless communication. A wireless signal passes through an antenna, a radio frequency channel module and A / D conversion to generate a digital signal, firstly spatial domain anti-interference processing is carried out on the digital signal, synchronous pulse capture is carried out on the processed signal to realize frequency hopping frequency synchronization, and a radio frequency signal module is controlled to carry out frequency hopping receiving; performing data pulse synchronization on the data after frequency hopping synchronization to complete signal code element synchronization, and sequentially completing carrier recovery, phase recovery and GMSK demodulation on the basis; and finally, carrying out de-interleaving, channel decoding and descrambling on the demodulated data, recovering information source data, and outputting the information source data. According to the method, spatial domain and frequency domain anti-interference processing is simultaneously realized in the signal receiving process, reliable and stable transmission of signals can be ensured, and the anti-interference transmission requirement of node information in a TDMA network can be met.

Description

Technical Field

[0001] This invention relates to the field of ad hoc network transmission and wireless communication technology, and in particular to a space-frequency joint anti-interference signal reception method suitable for TDMA networks. Background Technology

[0002] Aerial unmanned swarms typically interconnect using ad hoc networks. These networks often face complex interference environments, necessitating anti-interference transmission strategies in their signal transmission design. Ad hoc network systems typically employ TDMA access, allocating different transmission time slots to each network node, which then polls and transmits service data within its respective time slot. Therefore, burst communication transmission is required. Based on this, designing a high-speed frequency-hopping burst communication transmission method can effectively resist interference.

[0003] In addition, aerial platforms are often equipped with array antennas, achieving full airspace coverage by installing multiple array antennas around the platform. By adjusting the weights of each antenna element, nulls can be created in the direction of airspace interference, thereby achieving anti-interference purposes.

[0004] Currently, in the design of signal transmission systems in traditional TDMA networks, only the spatial or frequency domain is considered for anti-interference design, resulting in weak anti-interference capabilities. It is necessary to comprehensively consider both spatial and frequency information for anti-interference signal transmission design. Summary of the Invention

[0005] In view of this, the present invention proposes a space-frequency joint anti-interference signal reception method suitable for TDMA networks. This method simultaneously implements spatial and frequency domain anti-interference processing during signal reception, ensuring reliable and stable signal transmission and meeting the anti-interference transmission requirements of node information in TDMA networks.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A space-frequency joint anti-interference signal reception method suitable for TDMA networks includes the following steps:

[0008] Step 1: Radio waves are received by the antenna, generating an analog radio frequency signal, which is then output to the radio frequency channel module;

[0009] Step 2: The frequency hopping controller generates a frequency hopping pattern using a random sequence generator and a frequency hopping seed sequence, and then places the frequency hopping pattern into the radio frequency channel module to achieve frequency hopping;

[0010] Step 3: The RF channel module receives the synchronization pulse frequency according to the frequency hopping pattern, generates an intermediate frequency analog signal, and outputs it to the A / D analog-to-digital converter;

[0011] Step 4: After the intermediate frequency analog signal undergoes A / D analog-to-digital conversion, digital down-conversion, and filtering, a baseband digital signal is generated;

[0012] Step 5: Perform spatial domain anti-interference processing on the baseband digital signal from Step 4 to generate a spatially anti-interference digital signal;

[0013] Step 6: Perform frequency domain anti-interference processing on the output spatial domain anti-interference digital signal from Step 5 to generate a frequency domain anti-interference digital signal.

[0014] Step 7: The capture module performs synchronous pulse capture on the digital signal after frequency domain anti-interference in Step 6 and outputs the capture position;

[0015] Step 8: Synchronize data pulses based on the capture position, and then extract data;

[0016] Step 9: Perform carrier recovery on the data extracted in Step 8 and output the carrier-recovered data;

[0017] Step 10: Perform phase recovery on the data after carrier recovery and output the phase-recovered data;

[0018] Step 11: Perform GMSK demodulation on the phase-recovered data and output the demodulated data;

[0019] Step 12: Perform deinterleaving operation on the demodulated data and output the deinterleaved data;

[0020] Step 13: Perform channel decoding on the deinterleaved data and output the channel-decoded data;

[0021] Step 14: Perform descrambling operation on the channel-decoded data, output the descrambled data, and complete the space-frequency joint anti-interference signal reception suitable for TDMA networks.

[0022] Furthermore: the frequency hopping pattern in step 2 is generated by a 32nd-order pseudo-random sequence, with the initial phase being the reverse of the current time slot number, and each... The frequency hopping points within the time slot do not repeat and the adjacent intervals are greater than 100MHz.

[0023] Furthermore, the specific method for step 5 is as follows:

[0024] Step 501: Receive baseband digital signals through M array elements, and then perform down-conversion and digital signal sampling.

[0025] Step 502: Adaptively adjust the weights of the space-time filter to minimize the variance of the output signal. ;in for A dimensional vector representing the weighted values ​​of the matrix elements. This represents the number of elements in the array antenna. express The received signal sampling covariance matrix of dimension ; express A constraint matrix of dimension 1. express Dimensional constraint response vector, Indicates the number of constraints;

[0026] Step 503, construct the Lagrange function: ,make The optimal weight is obtained ;in This represents gradient calculation operation;

[0027] Step 504: Perform a weighted summation operation on the sampled data received from the multi-antenna channels and output the spatially anti-interference data.

[0028] Furthermore, the specific method for step 6 is as follows:

[0029] Step 601, in the space-frequency sensing interval The digital signal is processed by adding a Bartlett window, and then... Point FFT operation;

[0030] Step 602, for each FFT operation result... The points are partially accumulated and smoothed to obtain... Point operation result;

[0031] Step 603, in Select the smallest modulus from the point operation results. And calculate the adaptive threshold. ;

[0032] Step 604, based on the threshold The location of the interference was determined, and the frequency domain notch window function was selected. ;

[0033] Step 605, based on the selected frequency domain notch window function Windowing processing is applied to the digital signal at the interference location. Point FFT operation;

[0034] Step 606, in The threshold is calculated from the point operation result. ;

[0035] Step 607, based on the threshold Perform interference erasure and trap the FFT result at the corresponding position to zero;

[0036] Step 608: Perform IFFT operation and output the frequency domain anti-interference data.

[0037] Furthermore, the specific method for step 7 is as follows:

[0038] Step 701: Down-convert the digital signal at P frequency points; the P frequency points are the p frequency points in the frequency hopping pattern.

[0039] Step 702: Perform sliding conjugate complex multiplication between the captured local synchronization sequence and the down-converted digital signal;

[0040] Step 703, divide the conjugate complex multiplication result by length Perform partial accumulation to obtain the accumulated signal:

[0041] Step 704, perform processing on the accumulated signal. Perform point FFT operations and compare the results to find the maximum energy value.

[0042] Step 705: Delay and accumulate the maximum FFT energy of the synchronization pulse.

[0043] Step 706: Perform peak search and threshold judgment on the accumulated signal, and output the capture position.

[0044] Furthermore, the specific method for step 9 is as follows:

[0045] Step 901: After capture, read out the P cached synchronization pulse data in sequence;

[0046] Step 902: For each pulse readout data, perform a conjugate complex multiplication with the carrier recovery local synchronization sequence, and then calculate the result according to length. Perform partial accumulation to obtain the accumulated signal:

[0047] Step 903, fill the accumulated signal with zeros. Perform FFT operation on the points;

[0048] Step 904: The FFT results of all synchronization pulses are incoherently accumulated to obtain the peak value and calculate the carrier error;

[0049] Step 905: Generate a local compensation sine wave based on the carrier error, and multiply it with the signal to complete carrier recovery.

[0050] Furthermore, the specific method of step 10 is as follows:

[0051] Step 1001: Perform conjugate complex multiplication of the carrier-recovered data and the phase-recovered local synchronization sequence, and accumulate the results;

[0052] Step 1002: Calculate the phase angle of the accumulated result to obtain the phase offset and perform compensation.

[0053] Due to the adoption of the above technical solution, the beneficial effects of this invention compared with the prior art are as follows:

[0054] 1. The present invention employs both spatial and frequency domain anti-interference processing during signal reception, which can effectively improve the anti-interference performance of the system.

[0055] 2. This invention employs a parallel multi-frequency simultaneous acquisition algorithm, which can ensure fast and accurate acquisition in burst communication and achieve frequency hopping anti-interference reception in TDMA networks.

[0056] 3. This invention designs a fast convergence method for spatial anti-interference, which can realize fast spatial anti-interference processing for each frequency hopping point in a high-speed frequency hopping system. Attached Figure Description

[0057] Figure 1 This is a structural diagram of the receiving end in an embodiment of the present invention.

[0058] Figure 2 This is a diagram of the spatial anti-interference processing structure in an embodiment of the present invention.

[0059] Figure 3 This is a diagram of the synchronization pulse capture structure in an embodiment of the present invention.

[0060] Figure 4 This is a diagram of the carrier phase recovery structure in an embodiment of the present invention.

[0061] Figure 5 This is a structural diagram of the transmitting end in an embodiment of the present invention.

[0062] Figure 6 This is a time frame and time slot structure diagram in an embodiment of the present invention. Detailed Implementation

[0063] The invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0064] A space-frequency joint anti-interference signal reception method suitable for TDMA networks, such as Figure 1 As shown, it includes the following steps:

[0065] Step 1: Radio waves are received by the antenna, generating an analog radio frequency signal, which is then output to the radio frequency channel module;

[0066] Step 2: Working principle of the frequency hopping controller: A frequency hopping pattern is generated by a random sequence generator and a frequency hopping seed sequence. The frequency of the frequency hopping pattern at a certain moment is called the frequency hopping code, which is placed into the RF front-end phase-locked source to realize frequency hopping.

[0067] Step 3: The RF channel module receives the synchronization pulse frequency according to the frequency hopping pattern, generates an intermediate frequency analog signal, and outputs it to the A / D analog-to-digital converter; the total bandwidth of the frequency hopping pattern is 800MHz, and the range of the frequency hopping center frequency is [4, 795]MHz. The frequency step is 1MHz, and there are a total of 792 frequency points, with frequency point numbers from 0 to 791.

[0068] Generated from a 32nd-order pseudo-random sequence, with the initial phase being the current time slot number. Within each time slot, the frequency hopping points are not repeated and the adjacent intervals are greater than 100MHz. The specific method is as follows:

[0069] (1) Each time slot is determined by the time slot number. Using the reverse order of the first phase as the initial phase, a pseudo-random sequence is calculated based on the initial phase, with each 32 bits forming a binary number. ,calculate

[0070]

[0071] floor is the floor function; mod(x,y) is the function where x is the dividend and y is the remainder after division. That is The result mapped to 792 frequency points, The range is [0, 791]. The meaning is that the frequency difference between adjacent subnets is 40MHz at the same time. Let This is the frequency hopping point. First, calculate... Value and output frequency hopping point .

[0072] (2) Continue calculation .like and Between, there exists Then perform iterative calculations. .

[0073] (3) Judgment and all the center frequencies that have been generated Are there any duplicates? If there are no duplicates, then... If there is a duplicate, return to step (302).

[0074] (4) After calculating all frequency point values, P represents the total number of pulses.

[0075] Step 4: After the intermediate frequency analog signal undergoes A / D conversion, digital down-conversion, and filtering, a baseband digital signal is generated; the synchronous pulse down-conversion frequency is... In bandwidth Inside.

[0076] Step 5: Perform spatial domain anti-interference processing on the baseband digital signal from Step 3 to generate a spatially anti-interference digital signal; such as... Figure 2 As shown, the specific steps are as follows:

[0077] (1) Minimize the variance of the output signal by adaptively adjusting the weights of the space-time filter. ; in for A dimensional vector representing the weighted values ​​of the matrix elements. This represents the number of elements in the array antenna. express The received signal sampling covariance matrix of dimension . This represents the constraint matrix, and its size is... , The constraint response vector dimension is... ,in This indicates the number of constraints, which is typically selected in anti-interference systems. The constraint matrix and constraint response vector have no independent physical meaning; they are used together to characterize the constraint conditions, such as the desired signal being distortion-free or the interference direction being nulled. In this patent, It is related to the frequency output of the frequency hopping controller. Different frequencies should have different... .

[0078] (2) Because it is impossible to directly address To find the optimal solution, we need to construct the Lagrange function: ,make The optimal weight is obtained This expression is a general expression for the optimal weights; its specific value does not need to be calculated until it is simplified in step 3. This indicates gradient calculation operation.

[0079] (3) Simplify the calculation in step 2. In order to solve the minimum variance distortionless response in the communication system, select the constraint response vector. The linearly constrained minimum variance criterion degenerates into the minimum variance distortionless response. ;in It is known that the wave direction can be solved by the shape of the antenna array and the signal. The spatial steering vector of the array antenna.

[0080] (4) Solve the minimum variance distortionless response equation to obtain the optimal weight of the spatial anti-interference array. ; in for A dimensional vector represents the optimal weighted vector for spatial anti-interference.

[0081] (5) Perform a weighted summation operation on the sampled data received by the multi-antenna channels and output the data after spatial anti-interference.

[0082] Step 6: Perform frequency domain anti-interference processing on the spatial domain anti-interference digital signal output from Step 4 to generate a frequency domain anti-interference digital signal; the specific steps are as follows:

[0083] (1) In the space-frequency sensing interval Add a bartlett window within the interface.

[0084]

[0085] in, Let n be the window function index. Then, after adding the window, perform... Point FFT operation .

[0086] (2) For each FFT operation result, The points are partially accumulated and smoothed to obtain... dot operation result .

[0087] (3) In dot operation result Select the smallest modulus value And calculate the adaptive threshold. Among them, relative threshold With fixed threshold These are all adjustable coefficients for adaptive thresholds, derived from actual debugging. 1 < <128, 0< <255;

[0088] (4) Based on the threshold As a threshold, it will be greater than The value determines the location of the interference, and the frequency domain notch window function is selected.

[0089]

[0090] in, For frequency domain notch window functions, , , The frequency domain notch window adjustment coefficient is obtained through actual debugging, and its typical range is between 0 and 1, satisfying... , As the value increases, the main lobe energy increases and the stopband attenuation decreases; As the value increases, the main lobe energy narrows, and the side lobe level increases; Increasing the value increases the main lobe width and decreases the side lobe level. Adjusting the coefficients of the window function ensures its performance under different interference ratios and intensities. Aligning the frequency domain notch position with the interference position achieves anti-interference. N is the maximum value of the window length index.

[0091] (5) Based on the selected window function Windowing is applied to digital signals. Point FFT operation.

[0092] (6) In The threshold is calculated from the point operation result. ,in .in, and All are adjustable coefficients. 1 < <128, 0< <255;

[0093] (7) Based on the threshold Interference erasure is performed, and the FFT result at the corresponding position is trapped to zero.

[0094] (8) Perform IFFT operation and output the frequency domain anti-interference data.

[0095] Step 7: The acquisition module acquires the digital signal after frequency domain anti-interference in Step 5, outputs the acquisition position, completes frequency hopping synchronization, and controls the RF channel module to receive data pulses according to the frequency hopping pattern sequence; for example... Figure 3 As shown, the specific steps are as follows:

[0096] (1) Use local synchronization sequence With digital signals Performing sliding conjugate complex multiplication

[0097] ;

[0098] (2) Divide the result of conjugate complex multiplication by length Perform partial accumulation to obtain the accumulated signal:

[0099]

[0100] (3) Perform processing on the accumulated signal Point FFT operation, And by comparison Maximum energy value in the calculation results at each time step ;

[0101] (4) The maximum FFT energy of the synchronization pulse is delayed and accumulated, and the delay time is the pulse time. ,

[0102] (5) Perform peak search and threshold judgment on the accumulated signal, and output the capture position;

[0103] Step 8: Synchronize the symbols according to the capture position and output the synchronized data;

[0104] Step 9: Perform carrier recovery on the data after symbol synchronization and output the data after carrier recovery. For example... Figure 4 As shown, the specific steps are as follows:

[0105] (1) After capture, read out the buffered synchronization pulse data in sequence. ; ;

[0106] (2) Multiply the data read from each pulse by the conjugate of the local synchronization sequence: and according to length Perform partial accumulation to obtain the accumulated signal. :

[0107] (3) The accumulated signal is padded with zeros. Point FFT operation

[0108] (4) All synchronous pulse FFT calculation results are incoherently accumulated, and the accumulated results are... Find the maximum value to obtain the peak value. Let i be the index corresponding to the peak value, and calculate the carrier error. The digital resolution of the FFT is [value missing]. .

[0109] (5) Generate a locally compensated sine wave based on the carrier error. Carrier recovery is achieved by multiplying the signal with the carrier signal. ;

[0110] Step 10: Perform phase recovery with the data after carrier recovery, and output the phase-recovered data; the specific steps are as follows:

[0111] (1) The data pulse synchronization sequence is multiplied by the conjugate of the local synchronization sequence. And sum the results. ,in UW1, UW2, and UW3 represent the pulse synchronization sequence used for phase recovery.

[0112] (2) Calculate the phase angle of the accumulated results, obtain the phase shift, and compensate for it. ,in To find the arctangent function, In order to seek the truth, To find the imaginary part.

[0113] Step 11: Perform GMSK demodulation on the phase-recovered data and output the demodulated data;

[0114] Step 12: Perform deinterleaving operation on the demodulated data and output the deinterleaved data;

[0115] Step 13: Perform channel decoding on the deinterleaved data and output the channel-decoded data;

[0116] Step 14: Perform descrambling on the channel-decoded data and output the descrambled data;

[0117] Reference Figure 5 Corresponding to the above receiving method, the transmitting end adopts the following transmitting method:

[0118] Step 1: Generate a timeslot table and count timeslot numbers. The counting period within the time slot is The specific steps are as follows: the basic time slot period is... The time slot table period is , The periodic parameter is configurable; the transmission time slot is in the set. The selected time slot number.

[0119] Step 2: Calculate the frequency hopping pattern based on the current timeslot number. Specifically, the frequency hopping pattern is generated from a 32nd-order pseudo-random sequence, with the initial phase being the current timeslot number. Within each timeslot, the frequency hopping points are non-repeating and the adjacent intervals are greater than 100MHz. Before the synchronization pulse is acquired, the frequency hopping controller performs frequency hopping according to the search pattern; after the synchronization pulse is acquired, the frequency hopping controller performs frequency hopping according to the tracking pattern.

[0120] (1) Each time slot is determined by the time slot number. Using the reverse order of the first phase as the initial phase, a pseudo-random sequence is calculated based on the initial phase, with each 32 bits forming a binary number. , where i represents the pulse frequency index. Calculate

[0121]

[0122] floor is rounded down to the nearest integer. That is The result mapped to 792 frequency points, The range is [0, 791]. The meaning is that the frequency difference between adjacent subnets is 40MHz at the same time. First, calculate... Value and output frequency hopping point ,make This refers to the frequency hopping point.

[0123] (2) Continue calculation .like and Between, there exists Then perform iterative calculations. .

[0124] (3) Judgment and all the center frequencies that have been generated Are there any duplicates? If there are no duplicates, then... If there is a duplicate, return to step (302).

[0125] (4) After calculating all frequency point values, P represents the total number of pulses.

[0126] Step 3: Buffer the input data and count it within the time slot. The length read out at time is Source data;

[0127] Step 4: Perform source scrambling on the source data to obtain scrambled data;

[0128] Step 5: Perform channel coding on the scrambled data to obtain channel-coded data;

[0129] Step 6: Interleave the channel-coded data to obtain interleaved data, and input it into the buffer;

[0130] Step 7: As Figure 6 As shown, the count in the next time slot is When modulation and framing begin, a synchronization pulse sequence is first generated. The specific steps are as follows: the number of synchronization pulses is... One, using A length of pseudo-random sequence constitute

[0131] Step 8: As Figure 6 As shown, after the synchronization pulse is generated, data pulses are generated, data is read from the buffer, and synchronized with the UW sequence. The data pulses are composed of the following steps: the number of data pulses is... Each data pulse is divided into five parts, the first part being the UW field, with a length of [missing information]. pseudo-random sequence The second part is the data field, with a length of The data segment, the third part is the UW field, with a length of pseudo-random sequence The fourth part is the data field, with a length of The fifth part of the data segment is the UW field, with a length of [length missing]. pseudo-random sequence .

[0132] Step 9: Perform GMSK precoding on each pulse data. The specific steps of GMSK precoding are as follows:

[0133]

[0134] For the pre-coded bits, For precoded bits

[0135] Step 10: Modulate the precoded data using GMSK and output it sequentially according to the pulses;

[0136] Step 11: The modulated signal undergoes digital-to-analog conversion, and the synchronization pulse is frequency-converted according to the frequency hopping pattern at the baseband output, resulting in an output intermediate frequency of... Preserving the frequency cut interval between pulses The specific steps are as follows: Output the intermediate frequency point. In bandwidth Within, the space frequency sensing interval is preserved between pulses. The length meets the requirements for demodulation end spectrum interference detection and processing time. , This represents the number of sampling points for spectrum detection. To reduce the computational delay in spectrum processing, a simulated burst signal is obtained;

[0137] Step 12: The radio frequency channel module generates a frequency hopping signal based on the simulated burst signal and frequency hopping pattern information, and selects a specific antenna to transmit it to the wireless link.

[0138] Those skilled in the art will recognize that the described embodiments are intended to help readers understand the principles of the invention and should be understood as not limiting the scope of protection of the invention to the described embodiments. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the scope of the claims of the invention.

Claims

1. A space-frequency joint anti-jamming signal receiving method suitable for a TDMA network, characterized in that: The method comprises the following steps: Step 1: Radio waves are received by an antenna to generate a radio frequency analog signal and output to a radio frequency channel module; Step 2: A frequency hopping controller generates a frequency hopping pattern through a random sequence generator and a frequency hopping seed sequence, and places the frequency hopping pattern into the radio frequency channel module to realize frequency hopping; Step 3: The radio frequency channel module receives according to the frequency hopping pattern at a synchronous pulse frequency to generate an intermediate frequency analog signal and output to an A / D analog-to-digital converter; Step 4: After the intermediate frequency analog signal is subjected to A / D analog conversion and digital down conversion and filtering, a baseband digital signal is generated; Step 5: The baseband digital signal in step 4 is subjected to spatial anti-interference processing to generate a spatial anti-interference digital signal; Step 6: The spatial anti-interference digital signal output in step 5 is subjected to frequency domain anti-interference processing to generate a frequency domain anti-interference digital signal; Step 7: A capture module captures the frequency domain anti-interference digital signal in step 6 to output a capture position; Step 8: Data pulse synchronization is performed according to the capture position, and then data extraction is performed; Step 9: Carrier recovery is performed on the data extracted in step 8 to output carrier-recovered data; Step 10: Phase recovery is performed on the carrier-recovered data to output phase-recovered data; Step 11: GMSK demodulation operation is performed on the phase-recovered data to output demodulated data; Step 12: Deinterleaving operation is performed on the demodulated data to output deinterleaved data; Step 13: Channel decoding operation is performed on the deinterleaved data to output channel-decoded data; Step 14: De-scrambling operation is performed on the channel-decoded data to output de-scrambled data, and a spatial and frequency combined anti-interference signal receiving suitable for a TDMA network is completed.

2. The method according to claim 1, wherein the method is applied to a TDMA network. The frequency hopping pattern in step 2 is generated by a 32-order pseudo-random sequence, with initial phase being the inverse sequence of the current time slot number, and each The frequency hopping points in each time slot are not repeated and the adjacent interval is greater than 100 MHz.

3. The method according to claim 1, wherein the method is applied to a TDMA network. The specific manner of step 5 is as follows: Step 501: Baseband digital signals are received by M elements respectively, and then down conversion and digital signal sampling are performed; Step 502, minimizing the variance of the output signal by adaptively adjusting the weight of the space-time filter ; wherein is a M-dimensional vector representing the array element weight, is the number of array elements of the array antenna, represents a M x M received signal sample covariance matrix; represents a M x N constraint matrix, represents a N-dimensional constraint response vector, represents the number of constraint conditions; Step 503, constitute Lagrange function: , let get the optimal weight is ; wherein indicates gradient solution operation; Step 504: Weighted summation operation is performed on the sampling data received by the multiple antenna channels to output spatial anti-interference data.

4. The method of claim 1, wherein the method is applied to a TDMA network. The specific manner of step 6 is as follows: Step 601, in the space-frequency sensing interval The digital signal is subjected to Bartlett window processing, and after the windowing, point FFT operation is performed operation; Step 602, for each point of the FFT operation result, partial accumulation smoothing is performed to obtain a point operation result. Step 602, for each point of the FFT operation result, partial accumulation smoothing is performed to obtain a point operation result. Step 602, for each point of the FFT operation result, partial Step 603, in select the minimum modulus value in the point operation result and calculate the adaptive threshold ; Step 604, according to the threshold determine the interference position, and select the frequency domain notch window function ; Step 605, according to the selected frequency domain notch window function The window processing is performed on the interference position digital signal, and the Point FFT operation; Step 606, in The threshold value is calculated in the dot operation result ; Step 607, according to the threshold Interference cancellation is performed, and the FFT result corresponding to the position is nulled. Step 608: IFFT operation is performed to output frequency domain anti-interference data.

5. The method of claim 1, wherein the method is applied to a TDMA network. The specific manner of step 7 is as follows: Step 701: Digital signals are subjected to down conversion at P frequency points respectively; the P frequency points are p frequency points in the frequency hopping pattern; Step 702: A capture local synchronization sequence is used to perform sliding conjugate multiplication on the down-converted digital signals; Step 703, multiply the conjugate complex result by length partial accumulation to obtain an accumulated signal: Step 704, perform processing on the accumulated signal. Perform point FFT operations and compare the results to find the maximum energy value. Step 705: Delay accumulation is performed on the maximum value of the FFT energy of the synchronous pulse Step 706: Peak value searching and threshold judgment are performed on the accumulated signal to output a capture position.

6. The method of claim 1, wherein the method is applied to a TDMA network. The specific manner of step 9 is as follows: Step 901: P synchronous pulse data cached after capture are read out in sequence; Step 902, for each pulse readout data is multiplied with the carrier recovery local synchronization sequence conjugate respectively, and according to the length Partial accumulation is carried out to obtain the accumulated signal: Step 903, accumulate signal zero to perform FFT operation; Step 904: Non-coherent accumulation is performed on the FFT operation results of all the synchronous pulses to obtain a peak value and calculate a carrier error; Step 905: A local compensation sine wave is generated according to the carrier error, and complex multiplication is performed on the signal to complete carrier recovery.

7. The method of claim 1, wherein the method is applied to a TDMA network. The specific manner of step 10 is as follows: Step 1001: Complex multiplication is performed on the carrier-recovered data and a phase recovery local synchronization sequence, and the result is accumulated; Step 1002, the accumulated result is phase-angled to obtain a phase offset and to compensate.

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