CN108957419A - Asynchronous interference suppressing method based on notch filter processing - Google Patents

Abstract

The invention discloses an asynchronous interference suppression method based on wave-limiting filter processing, the main idea of which is: determine the airborne radar, the airborne radar has a target within the detection range, and the airborne radar transmits a signal to the detection range and passes the The echo signal received after target reflection is recorded as the radar original echo data matrix; according to the radar original echo data matrix, the range-Doppler domain data matrix is obtained; then the main lobe clutter is determined; the main lobe clutter is calculated wave Doppler frequency, and get a column vector g of length R; where R is a positive integer greater than 1; determine the reference threshold Get the modified result g _pro and the normalized power and vector G in turn, and then get the notch filter weight coefficient vector F; use the notch filter weight coefficient vector F to perform sliding window on the radar original echo data matrix processing to obtain a result after sliding window processing, and the result after sliding window processing is the asynchronous interference suppression result based on wave-limiting filtering processing.

Description

Asynchronous Interference Suppression Method Based on Notch Filter Processing

technical field

The invention belongs to the field of radar technology, in particular to an asynchronous interference suppression method based on wave-limiting filter processing, which is suitable for airborne radar echo asynchronous interference suppression.

Background technique

With its unique combat characteristics, airborne radar is regarded as a strategic weapon that can influence the battlefield situation by the military of various countries. Interference suppression performance is the main factor affecting the normal detection of airborne radar. Therefore, airborne radar interference suppression technology has attracted the attention of researchers from all over the world.

In the radar signal environment, interference always exists; common interference can be mainly divided into four types: deceptive interference, blocking interference, point frequency (vertical stripe) interference and asynchronous interference; among them, asynchronous interference (Asynchronous Interference) mainly comes from industrial The electromagnetic radiation of production equipment, communication equipment, other radars, etc., asynchronous interference is characterized by random occurrence in the form of narrow pulses, and the amplitude is much larger than the noise floor, so it is also called singular value (Singular Value); from the source, its It should have a certain periodicity, but its frequency of occurrence is inconsistent with the working pace of the radar; therefore, the time of asynchronous interference in the radar receiver is not fixed, showing great randomness.

On the other hand, the amplitude of asynchronous interference is very large, far greater than the signal and noise level values, and sometimes even reaches the level of clutter; asynchronous interference is shown in the pulse Doppler (PD, Pulse Doppler) diagram as having a certain range in the distance domain. width, the horizontal stripes filled in the Doppler domain; in radar signal detection, because its width is similar to the echo signal of the target, it is usually detected as a target; in automatic detection, dot trace aggregation technology is usually used to Reduce the number of original traces; and because the intensity of asynchronous interference is too strong, if there is a target appearing near it, the asynchronous interference will cover the target appearing in its neighborhood due to the trace aggregation algorithm, resulting in Targets will be inexplicably lost or have errors at certain moments (specifically, the radar detects singular values), which will affect the detection performance of the radar on the target; in addition, the radar often uses the accumulation method to improve the detection probability of the target, due to the asynchronous interference signal The existence of , will significantly increase the accumulated noise floor of each channel, which in turn will reduce the detection probability of the target.

Asynchronous interference has a high probability and intensity in some frequency bands (especially meter wave) and some occasions, but in other environments it has little influence or even does not appear; therefore, it is necessary to design an automatic Adaptive methods are used to deal with asynchronous interference. When asynchronous interference occurs, it is suppressed and eliminated. When there is no asynchronous interference, no suppression operation is performed to reduce signal processing loss.

Contents of the invention

Aiming at the problems existing in the above-mentioned prior art, the object of the present invention is to propose an asynchronous interference suppression method based on wave-limiting filter processing, which can adaptively suppress asynchronous interference. When interference occurs, the corresponding filter weight coefficients are adaptively calculated to eliminate it. When there is no asynchronous interference, no suppression operation is performed to reduce signal processing loss.

Realize the main train of thought of the object of the present invention: utilize radar original data matrix before carrying out pulse compression, asynchronous interference is shown as a thin line characteristic of single or several range gates after carrying out windowed Fourier transform in pulse dimension, calculate self-adaptive trap wave filter weight coefficient to suppress it.

In order to achieve the above-mentioned technical purpose, the present invention adopts the following technical solutions to achieve.

A method for asynchronous interference suppression based on wave-limiting filter processing, comprising the following steps:

Step 1, determine the airborne radar, there is a target in the detection range of the airborne radar, and the airborne radar transmits a signal to its detection range and the echo signal received after being reflected by the target is recorded as the radar original echo data matrix; Obtain the range-Doppler domain data matrix according to the radar original echo data matrix; then determine the main lobe clutter;

Step 2, calculating the Doppler frequency of the main lobe clutter, and according to the range-Doppler domain data matrix, obtain a column vector g of length R; wherein R is a positive integer greater than 1;

Step 3, according to the column vector g of length R, determine the reference threshold

Step 4, according to the reference threshold and the column vector whose length is R, obtain the modified result g _pro ;

Step 5, according to the modified and processed result g _pro and the reference threshold Get the normalized power and vector G;

Step 6, according to the normalized power and vector G, obtain the notch filter weight coefficient vector F;

Step 7, use the notch filter weight coefficient vector F to perform sliding window processing on the radar original echo data matrix, and obtain the result after sliding window processing, which is the asynchronous Interference suppression results.

Compared with the prior art, the present invention has the following advantages:

First, the present invention can adaptively suppress asynchronous interference of different distances and frequencies, and when data without asynchronous interference is processed, the adaptive filtering weight coefficients are all 1, so as to ensure that no processing loss is caused to signal data.

Second, the existing asynchronous interference suppression method uses two-pulse delay cancellation, and the cancellation result is modulo-delayed by one frame; FAR processing and the establishment and update of the range clutter map; the threshold value is detected, and the distance unit is recorded position, and fill in a threshold table; check the threshold table to determine the singular value position; the method of interpolating and replacing the signal at the asynchronous interference place with the adjacent signal interpolation, the calculation process is complicated and time-consuming; Raw data is processed by windowing, with less calculation, simple process and less time-consuming.

Description of drawings

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 1 is a kind of flow chart of the asynchronous interference suppression method based on wave limiting filter processing of the present invention;

Fig. 2 is the range Doppler spectrogram of the radar original echo data matrix;

Fig. 3 is a schematic diagram of the results obtained after the radar original echo data matrix is subjected to windowed Fourier transform along the pulse dimension;

Fig. 4 is the adaptive weight map obtained after calculation;

Fig. 5 is a schematic diagram of the results obtained after pulse compression and range Doppler processing after suppression by the present invention.

Detailed ways

Referring to Fig. 1, it is a flow chart of a method for asynchronous interference suppression based on wave-limiting filter processing of the present invention; wherein the asynchronous interference suppression method based on wave-limiting filter processing comprises the following steps:

Step 1, determine the airborne radar, there is a target within the detection range of the airborne radar, and the airborne radar transmits a signal to the detection range and the echo signal received after being reflected by the target is recorded as the radar original echo data matrix B _N×M'×R , the radar original echo data matrix B _N×M'×R is the data block of the array element number N multiplied by the pulse number M' multiplied by the range gate number R, and the radar original echo data matrix B _{N ×M'×R} is a three-dimensional matrix of N×M'×R, N represents the total number of array elements included in the airborne radar, and M' represents the number of elements emitted by the airborne radar within a coherent processing interval (CPI, Coherent Processing Interval). The total number of pulses, R represents the total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range.

Without pulse compression processing, the fast Fourier transform (FFT) transformation of the original radar echo data matrix B _N×M'×R is directly performed along the pulse dimension with the Chebyshev window, and the fast Fourier transform is obtained The three-dimensional matrix B _ceil of N×M×R after (FFT) transformation; each element in the three-dimensional matrix B _ceil of N×M×R after the fast Fourier transform (FFT) corresponds to a size of R×M The two-dimensional matrix, that is:

B _ceil = [B _ceil (1) B _ceil (2) ... B _ceil (i) ... B _ceil (N)]

Wherein, i=1,2,...,N, B _ceil (i) means that the size corresponding to the i-th element in the three-dimensional matrix B _ceil of N×M×R transformed by Fast Fourier Transform (FFT) is R ×M two-dimensional matrix, and the size of the i-th element in the N×M×R three-dimensional matrix B _ceil after fast Fourier transform (FFT) transformation corresponds to a two-dimensional matrix B _ceil (i ) includes R×M data, and its expression is:

Among them, b ₁₁ (i) represents the two _{-dimensional matrix B ceil (} i ) in the first range gate and the data at the first Doppler channel, b _1M (i) represents the i-th in the N×M×R three-dimensional matrix B _ceil after fast Fourier transform (FFT) transformation The array element corresponds to the data at the first range gate and the Mth Doppler channel in the two-dimensional matrix B _ceil (i) whose size is R×M, and b _R1 (i) represents the fast Fourier transform (FFT) The i-th element in the transformed N×M×R three-dimensional matrix B _ceil corresponds to the R-th range gate and the first Doppler channel in the R×M two-dimensional matrix B _ceil (i) data, b _RM (i) represents the two _{-dimensional matrix B ceil (} i) The data at the R-th range gate and the M-th Doppler channel inside.

Each element in the N×M×R three-dimensional matrix B _ceil after the fast Fourier transform (FFT) is accumulated corresponding to a two-dimensional matrix with a size of R×M, and then the transformed frequency domain data block is obtained , recorded as range-Doppler domain data matrix B _FFT , its calculation expression is:

At this time, the range-Doppler domain data matrix B _FFT is a two-dimensional matrix of R×M, and the range-Doppler domain data matrix B _FFT includes R×M range-Doppler domain data, and M represents the distance - The total number of Doppler channels included in the Doppler domain data matrix B _FFT is equal to the total number of pulses M' transmitted by the airborne radar within a coherent processing interval (CPI, Coherent Processing Interval); R means The total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range.

The largest radiation beam in the airborne radar’s transmitted signal to its detection range is defined as the main lobe beam, the irradiation direction of the main lobe beam is defined as the main beam pointing, and the main lobe beam is irradiated to the ground and reflected by the ground. The signal is defined as the main lobe clutter; because the fast Fourier transform is performed to transform the signal from the time domain to the frequency domain, the main lobe clutter will be compressed and gathered, and the expression in the range-Doppler diagram is as follows: Doppler frequencies (responses in the Doppler channel) form a vertical line with a certain width, as shown in Figure 2 at No. 30 Doppler channel.

Step 2, calculate the Doppler frequency f _d of the main lobe clutter:

Among them, v is the flight speed of the airborne radar carrier, λ is the wavelength of the signal transmitted by the airborne radar to its detection range, _φ0 is the angle between the main beam pointing and the flight speed direction of the airborne radar carrier, according to the airborne The geometric relationship of radar-carrying aircraft flight can be obtained as follows:

in, The azimuth angle of the main beam, θ ₀ is the elevation angle of the main beam, sin represents the sine function, and cos represents the cosine function.

After obtaining the Doppler frequency f _d of the main lobe clutter, it is necessary to remove the clutter data with a Doppler frequency near f _d in the range-Doppler domain data matrix B _FFT to eliminate the influence of the main lobe clutter energy, Obtain the data in the clear area; here find the Doppler frequency f d of the main lobe clutter along the Doppler direction of the Doppler-pulse frequency domain data matrix B _FFT , and select the Doppler frequency f _d of the main lobe clutter The frequency f _d is the center and the length is The area of width R is denoted as A two-dimensional matrix, the In the two-dimensional matrix of The range-Doppler domain data are all eliminated, and the range-Doppler domain data matrix B _FFT described in After all the range-Doppler domain data are removed, the remaining two regions are spliced sequentially, that is, The two-dimensional matrix and The two-dimensional matrices are spliced sequentially to get A two-dimensional matrix B, the The two-dimensional matrix B denote the clear region, and the Each range-Doppler domain data in the two-dimensional matrix B of is clear area data.

again to the said Each row of the two-dimensional matrix B Doppler-pulse frequency domain data are added together, and the result after addition is recorded as the power sum of a range gate, and then the power sum of R range gates is obtained, and the power sum of R range gates is recorded as a length of The column vector g of R; where, R represents the total number of range gates included after the airborne radar divides its detection range.

Step 3. According to the previous analysis, we know that the amplitude of asynchronous interference in the radar signal is much larger than the noise floor, so it is specifically manifested as singular points in the clutter data. Therefore, it is necessary to remove the singular points. The specific method is as follows:

Sort the power sums of R distance gates in the column vector g of length R from small to large, record the result obtained after sorting from small to large as the sorted column vector g _sort of length R, and remove the length R The points with too large power in the sorted column vector g _sort of length R, because the sorted column vector g _sort of length R is the power sum of R distance gates after sorting from small to large, so only after the sorting of length R Just select the data in the appropriate position in the column vector g _sort .

The specific method is: add the power sum of the first range gate in the sorted column vector g _sort of length R to the first The power sum of the first range gate, and the first The power sum of the range gate and the power sum of the Rth range gate are all eliminated, and the remaining The power sums of the range gates are added sequentially, and the added result is divided by Then obtain the statistical average value, and use the statistical average value as a reference threshold Its calculation expression is:

in, g _sort (i') represents the power sum of the i'th range gate in the sorted column vector g _sort of length R, R represents the total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range.

Here, the power sum of the first distance gate in the sorted column vector g _sort of length R is removed to the first The power sum of each range gate is to ensure accuracy and prevent too small samples from interfering with the overall data samples.

Step 4, get the reference threshold obtained after a certain multiple of k As the threshold for subsequent detection and judgment, k here is a set ratio parameter, 1<k<10, and the value of k in this embodiment is 4; it can be modified according to different situations, and the length of the column vector g of R all less than The power of the range gate and all replaced by All the values greater than or equal to in the column vector g of length R The power sum of the range gate remains unchanged; and then the modified result g _pro is obtained. At this time, the modified result g _pro is a column vector with length R; where R represents the airborne radar’s detection range The total number of range gates included after division.

Step 5, modify the processed result g _pro about the reference threshold obtained in step 3 Perform normalization processing to obtain the normalized power and vector G, and its calculation expression is:

At this time, the normalized power sum vector G is a column vector with length R, and R represents the total number of range gates included after the airborne radar divides its detection range.

Step 6, perform an inversion operation on the normalized power and vector G obtained in step 5, and record the result obtained after the inversion operation as the notch filter weight coefficient vector F, and its calculation expression is:

F=1/G

At this time, the notch filter weight coefficient vector F is a column vector with a length of R, and R represents the total number of range gates included after the airborne radar divides its detection range.

Step 7: Use the sliding window algorithm to perform sliding window processing on the radar original echo data matrix B _N×M'×R along the pulse dimension with the notch filter weight coefficient vector F obtained in step 6, and obtain the result after sliding window processing , the result after the sliding window processing is the asynchronous interference suppression result based on wave-limiting filter processing; wherein, M' represents the total number of pulses transmitted by the airborne radar within a coherent processing interval (CPI, Coherent Processing Interval).

The advantages of the present invention can be further illustrated by the following simulation experiments.

(1) Experimental parameters and experimental conditions

The parameters used in this experiment are as follows:

1) The airborne radar antenna adopts a planar array of 2 rows × 16 columns, and the distance between the array elements is half the wavelength of the airborne radar transmission waveform. Then, the radar echo data with a size of N × M × R can be obtained after pitch filtering; the radar array Oblique side view array placement.

2) 101 coherent accumulation pulses are transmitted within the same coherent processing interval CPI, the pulse repetition frequency is 2.203kHz; the distance sampling frequency is 2MHz; the angle between the main beam pointing and the nose of the carrier aircraft is 176°, and the yaw angle is 5° ; The height of the carrier aircraft is 8.3 kilometers, and the horizontal uniform flight speed is 149m/s; the radius of the earth is 6378 kilometers.

(2) Experimental content and result analysis

A. In this experiment, normal pulse compression and pulse Doppler processing are performed on the original radar echo data matrix, and the processing results are shown in Figure 2; where the abscissa represents the number of Doppler channels of the signal, and the ordinate represents the signal It can be seen from Figure 2 that there are a large number of obvious horizontal stripes at the distance gates 50-150 and 670-770, and there are a small number of weak horizontal stripes at the distance gate 300. These horizontal stripes Streaks are asynchronous disturbances.

B. the radar echo data is processed according to the flow process of the present invention; Fig. 3 is the result schematic diagram obtained after the original echo data matrix of the radar is carried out windowed Fourier transform along the pulse dimension, comparing Fig. 2, it can be seen that the asynchronous interference at this time The energy of the energy is concentrated in range gates 50, 70, 90, 270, and 680, forming multiple thin horizontal lines with energy concentration; Figure 4 is the adaptive weight diagram obtained after calculation, and it can be seen that An adaptive notch is used to suppress interference, while the weights of the rest are all 1, which will not change the original radar echo data.

C. Figure 5 is a schematic diagram of the results obtained after pulse compression and range Doppler processing after the suppression of the present invention. Comparing Figure 2, it can be clearly seen that the horizontal stripes in the corresponding part of Figure 2 have disappeared in Figure 5, indicating asynchronous interference It has been effectively suppressed; from the results in Figure 5, the method of the present invention can effectively suppress asynchronous interference, and the suppression effect is very good.

In summary, the simulation experiment has verified the correctness, effectiveness and reliability of the present invention.

Obviously, those skilled in the art can carry out various modifications and variations to the present invention without departing from the spirit and scope of the present invention; Like this, if these modifications and variations of the present invention belong to the scope of the claims of the present invention and equivalent technologies thereof, It is intended that the present invention also encompasses such changes and modifications.

Claims (9)

1. an asynchronous interference suppression method based on wave-limiting filter processing, is characterized in that, comprises the following steps: Step 1, determine the airborne radar, there is a target in the detection range of the airborne radar, and the airborne radar transmits a signal to its detection range and the echo signal received after being reflected by the target is recorded as the radar original echo data matrix; Obtain the range-Doppler domain data matrix according to the radar original echo data matrix; then determine the main lobe clutter; Step 2, calculating the Doppler frequency of the main lobe clutter, and according to the range-Doppler domain data matrix, obtain a column vector g of length R; wherein R is a positive integer greater than 1; Step 3, according to the column vector g of length R, determine the reference threshold Step 4, according to the reference threshold and the column vector whose length is R, obtain the modified result g _pro ; Step 5, according to the modified and processed result g _pro and the reference threshold Get the normalized power and vector G; Step 6, according to the normalized power and vector G, obtain the notch filter weight coefficient vector F; Step 7, use the notch filter weight coefficient vector F to perform sliding window processing on the radar original echo data matrix, and obtain the result after sliding window processing, which is the asynchronous Interference suppression results. 2. A kind of asynchronous interference suppression method based on wave limiting filter processing as claimed in claim 1, it is characterized in that, in step 1, described radar original echo data matrix is B _{N * M ' * R} , and radar The original echo data matrix B _N×M'×R is a three-dimensional matrix of N×M'×R, N represents the total number of array elements included in the airborne radar, and M' represents the pulse emitted by the airborne radar within a coherent processing interval The total number, R represents the total number of range gates included after the airborne radar divides its detection range, PRF represents the pulse repetition frequency, B represents the bandwidth of the airborne radar to transmit signals within its detection range; Described range-Doppler domain data matrix, its obtaining process is: Perform fast Fourier transform transformation with Chebyshev window on the original radar echo data matrix B _N×M’×R along the pulse dimension, and obtain the N×M×R three-dimensional matrix B _ceil after fast Fourier transform transformation , whose expression is: B _ceil = [B _ceil (1) B _ceil (2) ... B _ceil (i) ... B _ceil (N)] Among them, i=1,2,...,N, B _ceil (i) represents the size of the R×M binary matrix corresponding to the i-th array element in the three-dimensional matrix B _ceil of N×M×R after Fast Fourier Transformation Dimensional matrix; M represents the total number of Doppler channels included in the range-Doppler domain data matrix B _FFT , and is equal to the total number of pulses M' emitted by the airborne radar in a coherent processing interval; Each element in the N×M×R three-dimensional matrix B _ceil after the fast Fourier transform is accumulated corresponding to a two-dimensional matrix with a size of R×M, and then the transformed frequency domain data block is obtained, which is denoted as Range-Doppler domain data matrix B _FFT , its calculation expression is: The range-Doppler domain data matrix B _FFT is an R×M two-dimensional matrix, and the range-Doppler domain data matrix B _FFT includes R×M pieces of Doppler-pulse frequency domain data. 3. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 1, is characterized in that, in step 1, described main lobe clutter, its determination process is: The largest radiation beam in the airborne radar’s transmitted signal to its detection range is defined as the main lobe beam, the irradiation direction of the main lobe beam is defined as the main beam pointing, and the main lobe beam is irradiated to the ground and reflected by the ground. The signal is defined as main lobe clutter. 4. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 2 or 3, it is characterized in that, in step 2, the Doppler frequency of described main lobe clutter is f _d , its calculation The expression is: Among them, v is the flight speed of the airborne radar carrier, λ is the wavelength of the signal emitted by the airborne radar to its detection range, and _φ0 is the angle between the main beam pointing and the flight speed direction of the airborne radar carrier; The column vector whose length is R, its obtaining process is: Find the Doppler frequency f _d of the main lobe clutter along the Doppler direction of the Doppler-pulse frequency domain data matrix B _FFT , and select the Doppler frequency f _d of the main lobe clutter as the center, and the length is The area of width R is denoted as A two-dimensional matrix, the In the two-dimensional matrix of The range-Doppler domain data are all eliminated, and the range-Doppler domain data matrix B _FFT described in After all the range-Doppler domain data are removed, the remaining two regions are spliced sequentially, that is, The two-dimensional matrix and The two-dimensional matrices are spliced sequentially to get The two-dimensional matrix B; again to the said Each row of the two-dimensional matrix B Doppler-pulse frequency domain data are added together, and the result after addition is recorded as the power sum of a range gate, and then the power sum of R range gates is obtained, and the power sum of R range gates is recorded as a length of The column vector g of R; where, R represents the total number of range gates included after the airborne radar divides its detection range. 5. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 4, is characterized in that, in step 3, described reference threshold Its determination process is: Put the power sum of the first range gate in the sorted column vector g _sort of length R to the first The power sum of the first range gate, and the first The power sum of the range gate and the power sum of the Rth range gate are all eliminated, and the remaining The power sums of the range gates are added sequentially, and the added result is divided by Then obtain the statistical average value, and use the statistical average value as a reference threshold Its calculation expression is: in, g _sort (i') represents the power sum of the i'th range gate in the sorted column vector g _sort of length R, R represents the total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range. 6. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 1, it is characterized in that, in step 4, the result _gpro after the described modification process, its obtaining process is: In the column vector g of length R, all less than The power of the range gate and all replaced by All the values greater than or equal to in the column vector g of length R The power sum of the range gate remains unchanged; then the modified result g _pro is obtained, and the modified processed result g _pro is a column vector whose length is R; wherein, k represents the set ratio parameter, 1<k<10; R represents the total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range. 7. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 1, is characterized in that, in step 5, described normalized power and vector G, its obtaining process is: For the modified and processed results g _pro about the reference threshold Perform normalization processing to obtain the normalized power and vector G, and its calculation expression is: The normalized power and vector G is a column vector with a length of R, and R represents the total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range. 8. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 1, is characterized in that, in step 6, described notch filter weight coefficient vector F, its computing expression is: F=1/G The notch filter weight coefficient vector F is a column vector with a length of R, and R represents the total number of range gates included after the airborne radar divides its detection range, PRF stands for Pulse Repetition Frequency, and B stands for the bandwidth of the airborne radar transmitting signals within its detection range. 9. A kind of asynchronous interference suppression method based on wave-limiting filter processing as claimed in claim 6, is characterized in that, in step 7, the result after described sliding window processing, specifically uses sliding window algorithm to use described trapping window The wave filter weight coefficient vector F is the result obtained after sliding window processing on the radar original echo data matrix B _N×M’×R along the pulse dimension; where M’ represents the total number of pulses emitted by the airborne radar within a coherent processing interval number.