Anti-Intermittent Sampling Repeater Jamming Method Based on Energy Function and Band-Pass Filtering

Abstract

The present invention discloses an anti-intermittent sampling and repeater jamming method based on an energy function and band-pass filtering, comprising the following steps: After performing de-slope processing on the received signal of a linear frequency modulation pulse radar system, calculate the energy function, analyze the time-domain discontinuity characteristics, and obtain the selection criterion for the required threshold; construct a mask for removing the interference signal segment, perform smoothing processing, obtain a screening function for the target echo signal, and multiply it with the received signal to extract the signal segment without intermittent sampling and repeater jamming (ISRJ); construct a band-pass filter with low side lobes, perform band-pass filtering on the matched filtering result of the received signal, obtain the pulse compression result after anti-jamming, perform MTD and CFAR after data rearrangement to obtain the target peak position, and calculate the distance and velocity of the target. The present invention can effectively suppress intermittent sampling and repeater jamming even under low signal-to-noise ratio conditions, retain the target signal, improve the target detection probability, and has a relatively low computational complexity for signal processing.

Description

Technical Field

[0001] The present invention belongs to the field of radar information technology, and particularly relates to an anti-interrupted sampling repeater jamming method based on an energy function and band-pass filtering. Background Art

[0002] Interrupted sampling repeater jamming (ISRJ) is a new type of radar main lobe jamming method proposed by researchers such as Wang Xuesong from the National University of Defense Technology in 2007. It is implemented by a device called digital radio frequency storage. The ISRJ jammer samples a short segment of the signal and retransmits it, and then repeats this process until the pulse ends. Therefore, the jamming signal can reach the radar receiver within the same range gate as the real target echo. Since the signal retransmitted by the jammer with a digital radio frequency storage device is coherent with the radar transmitted signal, the jamming signal can obtain a very high signal processing gain after pulse compression, and the retransmitted jamming signal has only a one-way attenuation in space relative to the target echo. Thus, the ISRJ jammer can form more and stronger electronic false targets in the radar with very little transmitted energy.

[0003] After the ISRJ method was proposed, electronic counter-countermeasure algorithms against ISRJ have attracted much attention. In-phase and quadrature phase-frequency coded signals in the pulse and in-phase and quadrature linear frequency modulation-phase coded signals in the pulse were proposed successively. Their basic idea is to split the transmitted pulse into multiple orthogonal sub-signals, and use the characteristic that the sub-signal matching filter only accumulates the energy of the corresponding sub-signal to effectively counter the jamming. Some other scholars proposed anti-jamming schemes based on band-pass filtering. They generate specific band-pass filters using the discontinuous characteristics of the time-frequency analysis of the radar echo signal to retain the target signal in the pulse compression result and filter out the jamming. However, when the jamming parameters change within a coherent processing time, in the above methods, the matching filters of the signals selected within each pulse repetition time are not all the same, and the band-pass filters for the pulse compression results within each pulse repetition time are not all the same either, which will lead to incorrect moving target detection results. Later, some scholars proposed interference parameter estimation and interference reconstruction elimination based on the adaptive CLEAN algorithm and deconvolution algorithm to suppress ISRJ of LFM signals. However, when the ISRJ jammer adds an additional false target Doppler frequency shift, the above algorithms will fail. Summary of the Invention

[0004] The purpose of the present invention is to provide an anti-interrupted sampling repeater jamming method based on an energy function and band-pass filtering to suppress interrupted sampling repeater jamming, retain the target signal, and improve the target discovery probability.

[0005] The technical solution for achieving the object of the present invention is as follows: An anti-intermittent sampling and retransmission interference method based on an energy function and band-pass filtering, comprising the following steps:

[0006] Step 1, after performing de-slope processing on the received signal of a linear frequency modulation pulse radar system, calculate its energy function, analyze the time-domain discontinuity characteristics of the energy function, and obtain the selection criterion for the threshold required to extract the target echo signal;

[0007] Step 2, by comparing the energy function with the selected threshold, construct a mask for removing the interference signal segment, perform smoothing processing on it, obtain the screening function of the target echo signal, and multiply it with the received signal to extract the signal segment without intermittent sampling and retransmission interference (ISRJ);

[0008] Step 3, use the extracted target echo signal to construct a band-pass filter with low side lobes, perform band-pass filtering on the matched filtering result of the received signal, obtain the pulse compression result after anti-interference, perform moving target detection (MTD) and constant false alarm rate detection (CFAR) after data rearrangement to obtain the target peak position, and thus calculate the distance and speed of the target.

[0009] An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein when the processor executes the program, the above anti-intermittent sampling and retransmission interference method based on an energy function and band-pass filtering is implemented.

[0010] A computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the above anti-intermittent sampling and retransmission interference method based on an energy function and band-pass filtering is implemented.

[0011] Compared with the prior art, the present invention has the following significant advantages: (1) In the range of signal-to-noise ratio above -5 dB and interference-to-signal ratio below 20 dB, the present invention can effectively suppress intermittent sampling and retransmission interference, and can greatly improve the signal-to-interference ratio after signal processing, thereby increasing the target detection probability; (2) The present invention can perform real-time processing on the data of each pulse repetition interval (PRI). Even if the parameters of the interference signal change within a coherent processing interval (CPI), the band-pass filter can adaptively change accordingly to ensure the correctness of the MTD result; (3) This method does not require time-frequency analysis such as short-time Fourier transform, only needs to calculate the energy function of the radar signal, has a low computational complexity, a simple principle, and can achieve good real-time performance even with low-cost devices, and has competitiveness in terms of performance and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1(a) is a schematic diagram of an interference sampling signal, and FIG. 1(b) is a comparison diagram of the received signals without ISRJ interference and with ISRJ interference.

[0013] Figure 2It is the flowchart of the signal processing of the present invention.

[0014] Figure 3 It is the schematic diagram of the energy function of the present invention.

[0015] Figure 4 It is the schematic diagram of the mask and the target echo signal screening function in the present invention.

[0016] Figure 5 It is the schematic diagram of the signal segment extracted from the present invention without ISRJ interference.

[0017] Figure 6 It is the schematic diagram of the band-pass filtering function of the present invention.

[0018] Figures 7(a) to 7(d) It is the comparison chart before and after anti-interference of the present invention, where Figure 7(a) is the schematic diagram of pulse compression before anti-interference, Figure 7(b) is the schematic diagram of pulse compression after anti-interference, Figure 7(c) is the schematic diagram of MTD before anti-interference, and Figure 7(d) is the schematic diagram of MTD after anti-interference.

[0019] Figures 8(a) to 8(c) It is the processing gain and target detection probability of the present invention under different signal-to-noise ratios and interference-to-signal ratios, where Figure 8(a) is the schematic diagram of processing gain, Figure 8(b) is the schematic diagram of target detection probability after anti-interference, and Figure 8(c) is the schematic diagram of target detection probability before anti-interference. Specific implementation manner

[0020] The present invention proposes an anti-intermittent sampling and retransmission interference method based on energy function and band-pass filtering, which mainly includes three parts: calculating the energy function of the received signal and selecting the threshold, extracting the target echo signal segment without ISRJ, and constructing a band-pass filter and subsequent signal processing.

[0021] Step 1: Calculate the energy function of the received signal and select the threshold: After performing de-slope processing on the received signal of the linear frequency modulation pulse system radar, calculate its energy function. Among them, the energy of the target echo part not affected by interference is small and stable, and the energy of the received signal segment containing interference is large and has strong fluctuations. After analyzing the time-domain discontinuity characteristics of the energy function, the selection criterion for the threshold required to extract the target echo signal is obtained;

[0022] Assume that the normalized linear frequency modulation LFM baseband signal is

[0023]

[0024] Among them,

[0025]

[0026] K is the frequency modulation slope of the LFM signal, and T p is the pulse width of the transmitted signal.

[0027] Assume that there is only one scattering point in the real target used in the present invention, and the distance between it and the radar is R t . Then, the target echo signal can be written as

[0028]

[0029] where τ tar is the target echo time delay, τ tar = 2R t / c, c is the speed of light, and A r is the target echo amplitude.

[0030] The basic idea of ISRJ is "store - forward - store - forward". That is to say, the jammer first samples and stores part of the radar signal, and then forwards it to the other radar, repeating like this until the radar transmission signal ends. Let T r be the sampling repetition period of the jammer, and τ be the sampling pulse width. Then, the sampling pulse signal of the ISRJ jammer can be expressed as

[0031]

[0032] Then, the received ISRJ model can be expressed as

[0033]

[0034] A j is the interference amplitude, and N r is the number of interference sampling pulses in one transmitted signal pulse width.

[0035] The schematic diagram of the received signal of the present invention is shown in Fig. 1(a) and Fig. 1(b). Fig. 1(a) is the schematic diagram of the interference sampling signal, and Fig. 1(b) is the comparison diagram of the received signals with and without ISRJ interference.

[0036] After receiving the signal, signal processing is started, Figure 2 which is the flowchart of signal processing.

[0037] For ISRJ interference, since the signal forwarded by the jammer is coherent with the radar transmitted signal, multiple false target peaks can be formed in the pulse compression result of the LFM signal received by the radar.

[0038] Desloping processing is one of the common methods for broadband LFM signals. After desloping, the target echo signal will become a single - frequency signal. The desloped target echo signal can be expressed as

[0039]

[0040] The expression of the interference signal after de - sloping processing is

[0041]

[0042] Define the energy function as the square of the modulus of the signal. Analyze the distribution characteristics of the radar received signal in the time - energy domain when there is interference through the energy function. The de - sloped target echo s t_de (t), the interference signal s j_de (t), and the energy functions of the received signal x(t)=s t_de (t)+s j_de (t) are as follows

[0043]

[0044]

[0045]

[0046] Among them, is the additional phase.

[0047] To achieve effective interference, the power of the interference is generally much greater than the power of the target echo. The ISRJ jammer does not send interference signals when sampling the radar signal, so the time - frequency distribution of the received signal is discontinuous. The schematic diagram of the energy function of the present invention is as Figure 3 shown. By comparing the energy function curves of the de - sloped target echo signal, the ISRJ signal, and the radar received signal, it can be found that during the sampling period, the energy is stable and very small because the jammer does not send interference signals and only receives the target echo signal, while the energy fluctuates rapidly and strongly during the period of sending interference signals. Thus, a band - pass filter can be constructed to extract the signal segment without ISRJ.

[0048] When extracting the target echo signal segment not affected by interference, a suitable threshold needs to be set for the energy function of the received signal.

[0049] Since the received signal is the superposition of the target echo and the interference signal, there is always E t (t)≥A r 2 . Without considering the influence of noise, or when the noise is small, according to Equation (10), it can be seen that in the received signal segment with interference, there is (A j -A r ) 2 ≤E t (t)≤(A j +A r ) 2 . So when (A j -A r )2 ≥A r 2 , that is, A j ≥2A r When, a threshold γ can be found to satisfy A r 2 <γ<(A j -A r ) 2 , this threshold is larger than the value of the received signal energy function with only the target echo band and smaller than the value of the received signal energy function with the interference section. Therefore, by comparing E x (t) with γ, a screening function for the target echo signal can be obtained.

[0050] Calculate the threshold γ through the following formula:

[0051]

[0052] Generally, there is So the threshold obtained from formula (11) satisfies A r 2 <γ<(A j -A r ) 2 .

[0053] Step 2: Extract the target echo signal segment without ISRJ: By comparing the energy function with the selected threshold, a mask for removing the interference signal segment is constructed. After smoothing it, the influence of noise is further reduced to obtain a screening function for the target echo signal, and multiplying it with the received signal extracts the "pure" signal segment without the intermittent sampling and retransmission jamming (ISRJ);

[0054] By comparing the energy function E x (t) of the received signal with the threshold γ, a mask c(t) is constructed. When noise is not considered or the noise is small, for any moment t0 in the radar received signal x(t), if E x (t0)<γ, then c(t0) = 1, otherwise c(t0) = 0. Then the signal segment not interfered by the ISRJ signal can be expressed as h(t) = x(t)·c(t).

[0055] When the noise cannot be ignored, the envelope of the energy function will no longer be constant. When the noise is large enough, if a fixed threshold is used to extract the signal segment not interfered by the ISRJ signal, the sharp fluctuations of the energy function will cause a large amount of interference signals to leak into the extracted target echo band. Then the band-pass filter function constructed subsequently will have high sidelobes, thus introducing large errors in the subsequent processing. To solve the problem of interference leakage, an envelope extraction of the mask c(t) needs to be done to remove the fluctuating spikes. The specific steps are as follows:

[0056] ① Find the time coordinates I(i) corresponding to all the points with a value of 1 in c(t), arrange the coordinates in ascending order, and use the coordinate of the next point minus the coordinate of the previous point as the coordinate interval spa(i), that is, spa(i) = I(i + 1) - I(i). Find the maximum value max(spa(i)) of the coordinate intervals, and use this maximum value minus a floating value ε as the interval threshold. Here, take ε = 10%×max(spa(i)). If the distance spa(i) of the time coordinates with a value of 1 in c(t) is less than the interval threshold, then set c(I(i + 1)) corresponding to the next time coordinate I(i + 1) to 0. Thus, the left boundary of each segment of interference that the mask needs to shield can be obtained based on c(t) being 1;

[0057] ② Arrange the time coordinates corresponding to all the points with a value of 1 in c(t) in descending order, and also find the coordinate intervals. If the coordinate interval is less than the interval threshold, then set c(t) corresponding to the previous time coordinate to 0. Thus, the right boundary of each segment of interference that the mask needs to shield can be obtained based on c(t) being 1;

[0058] ③ Add the left and right boundaries together, and what is obtained is the complete boundary of each segment of interference signal that the mask needs to shield, and it is defined as the screening function of the target echo signal.

[0059] The screening function of the target echo signal is smoother than the original mask and has a certain ability to suppress the influence of noise. Thus, the positions of the interference to be shielded and the target echo signal to be extracted in the received signal can be accurately located. Figure 4 The figure shows the schematic diagrams of the initial mask c(t) and the screening function of the target echo signal.

[0060] Assume that the screening function of the target echo signal is cho(t), then the received signal segment without the ISRJ signal extracted can be expressed as

[0061] h(t) = x(t)·cho(t) (12)

[0062] Figure 5 It shows the signal segment extracted without being interfered by ISRJ.

[0063] Step 3: Construct a band - pass filter and subsequent signal processing: Use the extracted target echo signal to construct a band - pass filter with low sidelobes, perform band - pass filtering on the matched filtering result of the received signal, obtain the pulse compression result after anti - interference, perform moving target detection MTD and constant false alarm rate detection CFAR after data rearrangement to obtain the target peak position, and thus calculate the distance and speed of the target.

[0064] Window the received signal segment h(t) without the ISRJ signal, then perform matched filtering, normalize it, and take the modulus to obtain the band-pass filtering function fil(t), that is

[0065]

[0066] where win(t) is the window function and pp(t) is the matched filter corresponding to the transmitted signal.

[0067] Figure 6 is the schematic diagram of the constructed band-pass filtering function.

[0068] Perform matched filtering on the received signal x(t) to obtain the result of pulse compression.

[0069]

[0070] Multiply mf(t) by the band-pass filtering function fil(t), and the ISRJ interference will be filtered out, obtaining the pulse compression result after anti-interference as follows

[0071] y(t) = mf(t) · fil(t) (15)

[0072] The above is the processing of the signal for one pulse repetition interval (PRI). After processing the data of one coherent processing interval (CPI), rearrange the data, perform Fourier transform on the data of each range bin, and thus obtain the MTD result. Next, use the ordered statistic constant false alarm rate (OS-CFAR) detection to detect the target peak. After obtaining the horizontal and vertical coordinates x and y of the target cell, the distance and speed of the target are obtained by the following formula

[0073]

[0074]

[0075] where f s is the data rate, λ is the wavelength of the transmitted signal, N is the number of PRIs in one CPI of the transmitted signal, and T is the PRI length of the transmitted signal.

[0076] Figures 7(a) to 7(d) is the comparison diagram before and after anti-interference. Figure 7(a) is the schematic diagram of pulse compression before anti-interference, Figure 7(b) is the schematic diagram of pulse compression after anti-interference, Figure 7(c) is the schematic diagram of MTD before anti-interference, and Figure 7(d) is the schematic diagram of MTD after anti-interference.

[0077] The present invention can effectively suppress the intermittent sampling and forwarding interference even at low signal-to-noise ratios, retain the target signal, improve the target detection probability, and has a relatively low computational complexity of signal processing.

[0078] Embodiment

[0079] The effects of the present invention can be further illustrated by the following simulation experiments.

[0080] In the index design of the simulation experiment, the target distance is set at 1000 m and the speed is 100 m / s. According to the design method of the specific implementation, the waveform parameters of the radar and the jammer are designed as shown in Table 1:

[0081] Table 1

[0082]

[0083] When performing OS-CFAR on the MTD result, the window length of the sliding window used is 32, and the false alarm probability is 10 -6 .

[0084] To represent the influence of the signal-to-noise ratio SNR and the jammer-to-signal ratio JSR on the anti-jamming performance, the signal-to-jamming ratio improvement factor SJRIF and the target detection probability are used to reflect the performance of this method. SJRIF representing the processing gain can be expressed as

[0085] SJRIF = SJR OUT - SJR IN (18)

[0086] where SJR OUT represents the signal-to-jamming ratio SJR after anti-jamming processing, and SJR IN represents the SJR of the echo PRI.

[0087] Figures 8(a) to 8(c) The processing gain and the target detection probability in Matlab simulation under different signal-to-noise ratios and jammer-to-signal ratios are as follows. The input JSR range is from 5 dB to 30 dB, with a step of 5 dB, and the input SNR range is from -20 dB to 20 dB, also with a step of 5 dB.

[0088] Figure 8(a) shows the result of SJRIF. As the SNR increases, the processing gain brought by the present invention, that is, SJRIF, also increases. When the SNR is -10 dB, the processing gain under each JSR can reach 10 dB, and when the SNR is 0 dB, the processing gain under each JSR can reach 25 dB. Therefore, it can be seen that the present invention can effectively suppress the intermittent sampling and forwarding interference.

[0089] Figures 8(b) and 8(c) show the results of the target detection probability before and after anti-interference. It can be seen that before anti-interference, when the JSR is 10 dB, the target detection probability is 0, which means that the target has been completely submerged by interference. After anti-interference, the larger the SNR and the smaller the JSR, the higher the target detection probability. When the SNR is -10 dB and the JSR is 15 dB, the target detection probability is 95.10%. When the SNR is 0 dB and the JSR is 25 dB, the target detection probability also reaches 91.13%. Therefore, it can be seen that the energy function method can effectively improve the target detection probability.

[0090] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An anti-intermittent sampling and repeater jamming method based on an energy function and band-pass filtering, characterized in that It includes the following steps: Step 1: After performing de-slope processing on the received signal of a linear frequency modulation pulse radar, calculate its energy function, analyze the time-domain discontinuity characteristics of the energy function, and obtain the selection criterion for the threshold required to extract the target echo signal; Step 2: By comparing the energy function with the selected threshold, construct a mask for removing interference signal segments, perform smoothing processing on it to obtain the screening function of the target echo signal, and multiply it with the received signal to extract the signal segment without intermittent sampling and retransmission jamming (ISRJ); Step 3: Use the extracted target echo signal to construct a band-pass filter with low side lobes, perform band-pass filtering on the matched filtering result of the received signal to obtain the pulse compression result after anti-jamming, perform moving target detection (MTD) and constant false alarm rate detection (CFAR) after data rearrangement to obtain the target peak position, and thus calculate the distance and speed of the target.

2. The anti-intermittent sampling and repeater jamming method based on energy function and band-pass filtering according to claim 1, characterized in that, The steps of performing de-slope processing on the received signal of a linear frequency modulation pulse radar, calculating its energy function, analyzing the time-domain discontinuity characteristics of the energy function, and obtaining the selection criterion for the threshold required to extract the target echo signal in Step 1 are specifically as follows: Assume that the normalized linear frequency modulation (LFM) baseband signal is where K is the frequency modulation slope of the LFM signal, and T p is the pulse width of the transmitted signal; Assume that the true target has only one scattering point and the distance between it and the radar is R t ; then, the target echo signal can be written as where τ tar is the target echo time delay, τ tar = 2R t / c, where c is the speed of light, and A r is the target echo amplitude; Let T r be the sampling repetition period of the jammer and τ be the sampling pulse width. Then the sampling pulse signal of the ISRJ jammer can be expressed as Then the model of the received ISRJ can be expressed as A j is the interference amplitude, N r is the number of interference sampling pulses in a transmit signal pulse width; The target echo signal after de-slope is expressed as The expression of the interference signal after de-slope processing is Define the energy function as the square of the signal modulus, and analyze the distribution characteristics of the radar received signal in the time - energy domain when there is interference through the energy function; the target echo s t_de (t), the interference signal s j_de (t), and the energy functions of the received signal x(t) = s t_de (t) + s j_de (t) are as follows respectively wherein, is the additional phase; When extracting the target echo signal segment unaffected by interference, a suitable threshold needs to be set for the energy function of the received signal; since the received signal is the superposition of the target echo and the interference signal, there is always E t (t) ≥ A r 2 ; without considering the influence of noise, it can be seen from Equation (10) that within the received signal segment with interference, there is (A j - A r ) 2 ≤ E t (t) ≤ (A j + A r ) 2 ; so when (A j - A r ) 2 ≥ A r 2 , that is, A j ≥ 2A r , a threshold γ can be found to satisfy A r 2 < γ < (A j - A r ) 2 , this threshold is larger than the value of the energy function of the received signal in the target echo only segment and smaller than the value of the energy function of the received signal in the interference segment. Therefore, by comparing E x (t) with γ, the screening function of the target echo signal can be obtained; Calculate the threshold γ through the following formula:

3. The anti-intermittent sampling and forwarding jamming method based on an energy function and band-pass filtering according to claim 2, wherein There is Therefore, the threshold value obtained from Equation (11) satisfies A r 2 <γ<(A j -A r ) 2 .

4. The anti-intermittent sampling and repeater jamming method based on energy function and band-pass filtering according to claim 2, wherein The steps of constructing a mask for removing interference signal segments by comparing the energy function with the selected threshold, performing smoothing processing on it to obtain the screening function of the target echo signal, and multiplying it with the received signal to extract the pure signal segment without intermittent sampling and retransmission jamming (ISRJ) in Step 2 are specifically as follows: By comparing the energy function E of the received signal x (t) with the threshold γ, a mask c(t) is constructed. When noise is not considered, for any moment t0 in the radar received signal x(t), if E x (t0) < γ, then c(t0) = 1; otherwise, c(t0) = 0. Then the signal segment not interfered by the ISRJ signal can be expressed as h(t) = x(t)·c(t); Perform an envelope extraction on the mask c(t) to remove the fluctuating burrs, specifically as follows: ① Obtain the time coordinate I(i) corresponding to all points with a value of 1 in c(t), arrange the coordinates from small to large, use the coordinate of the latter point minus the coordinate of the previous point as the coordinate interval spa(i), that is, spa(i) = I(i + 1) - I(i); obtain the maximum value max(spa(i)) of the coordinate interval, subtract a floating value ε from this maximum value as the interval threshold, and here take ε = 10%×max(spa(i)); if the distance spa(i) of the time coordinate with a value of 1 in c(t) is less than the interval threshold, then set c(I(i + 1)) corresponding to the latter time coordinate I(i + 1) to 0, and thus the left boundary of each segment of interference that the mask needs to shield can be obtained according to c(t) being 1; ② Arrange the time coordinates corresponding to all points with a value of 1 in c(t) from large to small, and also calculate the coordinate interval. If the coordinate interval is less than the interval threshold, then set c(t) corresponding to the previous time coordinate to 0, and thus the right boundary of each segment of interference that the mask needs to shield can be obtained according to c(t) being 1; ③ Add the left and right boundaries to obtain the complete boundary of each segment of interference signal that the mask needs to shield, and define it as the screening function of the target echo signal; Assume that the screening function of the target echo signal is cho(t), then the received signal segment without ISRJ signal extracted is expressed as h(t) = x(t)·cho(t) (12).

5. The anti-intermittent sampling and forwarding jamming method based on an energy function and band-pass filtering according to claim 4, wherein As described in step 3, the band - pass filter with low sidelobes is constructed by using the extracted target echo signal, and the band - pass filtering is performed on the matched filtering result of the received signal to obtain the pulse compression result after anti - interference. After data rearrangement, moving target detection MTD and constant false alarm rate detection CFAR are performed to obtain the target peak position, and thus the distance and speed of the target are calculated as follows: Window the received signal segment h(t) without ISRJ signal, then perform matched filtering, and take the modulus after normalization processing to obtain the band - pass filtering function fil(t), that is where win(t) is the window function and pp(t) is the matched filter corresponding to the transmitted signal; Perform matched filtering on the received signal x(t) to obtain the result of pulse compression; Multiply mf(t) by the band - pass filtering function fil(t), and the ISRJ interference is filtered out to obtain the pulse compression result after anti - interference as follows: y(t) = mf(t)·fil(t) (15) The above is the processing of the signal in one pulse repetition interval PRI. After processing the data in one coherent processing interval CPI, the data is rearranged, and the Fourier transform is performed on the data of each range bin to obtain the result of MTD; then the ordered statistic constant false alarm rate detection OS - CFAR is used to detect the target peak. After obtaining the abscissa and ordinate x, y of the unit where the target is located, the distance and speed of the target are obtained from the following formula: where f s is the data rate, λ is the wavelength of the transmitted signal, N is the number of PRIs in one CPI of the transmitted signal, and T is the PRI length of the transmitted signal.

6. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the anti - intermittent sampling and forwarding interference method based on the energy function and band - pass filtering as described in any one of claims 1 - 5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the anti - intermittent sampling and forwarding interference method based on the energy function and band - pass filtering as described in any one of claims 1 - 5.

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