阅读说明：本技术 一种雷达干扰装备干扰效果评估方法 (Radar interference equipment interference effect evaluation method ) 是由 陈立明 崔瑞 章瑜 于 2020-04-22 设计创作，主要内容包括：本发明公开了一种雷达干扰装备干扰效果评估方法,包括以下步骤：1、从雷达干扰装备的信号接口采样雷达辐射源信号和干扰信号；2、对采样的雷达辐射源信号和干扰信号进行时频特征分析；3、根据信号相似度对干扰信号的干扰效果进行实时监测,对干扰样式选择的合理性、干扰参数设置的准确性进行定量分析,得出干扰效果评估结果；4、根据信号相似度分析结果判定干扰效果。本发明通过对雷达辐射源信号和干扰信号进行相似度分析,给出干扰信号的干扰效果评估,为作战训练实操评判提供参考依据,同时为装备操作人员进行干扰决策提供有效的技术支持。(The invention discloses a method for evaluating interference effect of radar interference equipment, which comprises the following steps: 1. sampling radar radiation source signals and interference signals from a signal interface of radar interference equipment; 2. performing time-frequency characteristic analysis on the sampled radar radiation source signals and interference signals; 3. monitoring the interference effect of the interference signal in real time according to the signal similarity, and carrying out quantitative analysis on the rationality of interference pattern selection and the accuracy of interference parameter setting to obtain an interference effect evaluation result; 4. and judging the interference effect according to the analysis result of the signal similarity. According to the method, the similarity analysis is carried out on the radar radiation source signal and the interference signal, the interference effect evaluation of the interference signal is given, a reference basis is provided for the actual operation judgment of combat training, and meanwhile effective technical support is provided for the interference decision of equipment operators.)

1. A method for evaluating interference effect of radar interference equipment is characterized by comprising the following steps:

s1, sampling radar radiation source signals and interference signals from a signal interface of the radar interference equipment;

s2, performing time-frequency characteristic analysis on the sampled radar radiation source signals and interference signals;

s3, monitoring the interference effect of the interference signal in real time according to the signal similarity, and carrying out quantitative analysis on the rationality of interference pattern selection and the accuracy of interference parameter setting to obtain an interference effect evaluation result;

the quantitative analysis process comprises the steps of distinguishing signals from different radar radiation sources through a signal sorting method based on QMF analysis, realizing the matching of a radar radiation signal source and an interference signal through a signal sorting method based on rising edge waveform matching, and finally completing the signal similarity analysis through waveform similarity measurement;

and S4, judging the interference effect according to the signal similarity analysis result.

2. The method for evaluating the interference effect of the radar interference equipment according to claim 1, wherein the signal processing adopts a ZFT frequency measurement method to perform frequency domain analysis on the signal, and the method is specifically implemented by firstly shifting the frequency of the acquired signal X into X', then performing low-pass filtering and resampling, and finally performing fast Fourier transform.

3. The method of claim 1, wherein the signal processing is performed by frequency domain analysis using a segmented FFT phase weighted frequency measurement method, and is specifically configured to divide x (n) into M non-overlapping groups, the data length is L points, and the sampled data is represented as s_i＝[x(iL),x(iL+1),…,x(iL+L)]Wherein i is 0,1, …, M-1, and performing L points FFT operation on the M groups of data to obtain s_iAfter the amplitude is accumulated, the signal frequency is roughly measured, and then phase weighting is carried out, and the signal frequency is accurately measured.

4. The method for evaluating the interference effect of the radar interference equipment according to claim 1, wherein signal processing adopts a time-frequency analysis method based on WVD to perform time-frequency analysis on the signals, and the method comprises the specific operations of ① obtaining sampled signals, performing Hilbert transform to obtain analysis signals of the sampled signals, ② determining window type, window length and window moving step, ③ moving a window, calculating instantaneous autocorrelation of data in the window by taking a window center as a reference point, ④ performing fast Fourier transform on the instantaneous autocorrelation, ⑤ moving the window by the window moving step, and repeating the steps ③, ④ and ⑤ until all data are processed.

5. The method of claim 1, wherein the specific operation of distinguishing the signals from different radar radiation sources by the QMF analysis-based signal sorting method is to perform orthogonal wavelet decomposition of the signals by QMF analysis, divide the input signal energy into orthogonal components in frequency by a two-channel orthogonal mirror filter bank, introduce the formed QMF pairs into a tree structure with a certain number of layers, make "blocks" in each layer have the same area size by waveform decomposition, input the output components of each filter into the QMF pairs in the next layer, each QMF pair decomposes the input signal waveform into two parts of high frequency component and low frequency component by pi, where "block" refers to a rectangular region containing the energy of basis function on the time-frequency plane.

6. The method of claim 5, wherein the quadrature mirror filter is an improved SINC filter with a transfer function ofWherein N is more than or equal to (N-2)/2 and less than or equal to N/2, C is a compression variable, S is a scale variable, N is the number of convolution points, and omega (N) is a Hamming window function for inhibiting Gibbs phenomenon.

7. The method for evaluating the interference effect of the radar interference equipment according to claim 5, wherein the matching of the radar radiation signal source and the interference signal is realized through a signal sorting method based on the rising edge waveform matching, and the method is specifically characterized in that ① extracts a pulse signal envelope and performs curve fitting, ② extracts the rising edge of the pulse signal envelope after the curve fitting, ③ judges the similarity of the radar radiation source signal and the rising edge waveform of the interference signal by adopting a Huasdorff distance method, and the matching of the radar radiation signal source and the interference signal is completed.

8. The method for evaluating the interference effect of the radar interference equipment according to claim 7, wherein the signal similarity analysis is completed through waveform similarity measurement, and the method is specifically implemented by ①, comparing radar radiation source signals and interference signal waveforms integrally by using an included angle cosine algorithm and a sliding window algorithm to obtain waveform basic similarity, ②, comparing amplitudes of the radar radiation source signals and the interference signal waveforms by using an average absolute difference algorithm to obtain amplitude similarity, and ③, weighting the waveform basic similarity and the amplitude similarity averagely to obtain a final similarity value of the radar radiation source signals and the interference signal waveforms.

9. The method for evaluating the interference effect of the radar interference equipment according to claim 8, wherein the evaluation criterion of the interference effect evaluation result is that the final similarity value is 95% or more, the interference effect is good, 80% to 95% is general, 65% to 80% is critical interference, and less than 65% is interference-free.

Technical Field

The invention relates to the technical field of radar interference evaluation, in particular to a method for evaluating interference effect of radar interference equipment.

Background

The radar is a very important military electronic device, and can obtain information of azimuth angle, pitch angle, speed, distance and the like of a target through the radar, which is called as 'eyes of electronic warfare'. With the development of radar technology, radar jamming technology has also been rapidly advanced. Radar jamming is electronic interference that degrades or even completely loses the performance of an enemy device by disturbing or spoofing the enemy's radar device. From the perspective of battle, the enemy radar system is destroyed and disturbed, so that the enemy radar system cannot accurately monitor the radar signal of the enemy, and tactics of successfully realizing the battle arrangement of the enemy are guaranteed.

The radar interference equipment is limited by various factors, does not generally emit strong-power interference signals in combat training, so that trained personnel have little knowledge of the characteristics of the interference signals, and often cannot judge whether the adopted interference patterns and the set interference signal parameters are reasonable or not, and cannot evaluate the interference effect on a target radar.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a method for evaluating the interference effect of radar interference equipment, which evaluates the interference effect of an interference signal by analyzing the similarity of a radar radiation source signal and the interference signal and provides a reference basis for actual operation judgment of combat training.

In order to solve the technical problem, the method for evaluating the interference effect of the radar interference equipment disclosed by the invention comprises the following steps of:

s1, sampling radar radiation source signals and interference signals from a signal interface of the radar interference equipment;

s2, performing time-frequency characteristic analysis on the sampled radar radiation source signals and interference signals;

s3, monitoring the interference effect of the interference signal in real time according to the signal similarity, and carrying out quantitative analysis on the rationality of interference pattern selection and the accuracy of interference parameter setting to obtain an interference effect evaluation result;

the quantitative analysis process comprises the steps of distinguishing signals from different radar radiation sources through a signal sorting method based on QMF analysis, realizing the matching of a radar radiation signal source and an interference signal through a signal sorting method based on rising edge waveform matching, and finally completing the signal similarity analysis through waveform similarity measurement;

and S4, judging the interference effect according to the signal similarity analysis result.

Further, the signal processing adopts a ZFT frequency measurement method to carry out frequency domain analysis on the signal, and the specific operation is that firstly, the acquired signal X is subjected to frequency shift to be changed into X', then, the X is subjected to low-pass filtering and re-sampling, and finally, fast Fourier transform is carried out, or the sectional FFT phase weighting frequency measurement method is adopted to carry out frequency domain analysis on the signal, the specific operation is that X (n) is divided into M groups which are not overlapped, the data length is L points, and the sampling data is expressed as s_i＝[x(iL),x(iL+1),…,x(iL+L)]Wherein i is 0,1, …, M-1, and performing L points FFT operation on the M groups of data to obtain s_iAfter the amplitude is accumulated, the signal frequency is roughly measured, and then phase weighting is carried out, and the signal frequency is accurately measured.

Further, signal processing adopts a time-frequency analysis method based on WVD to carry out time-frequency analysis on signals, and the specific operations are ① obtaining sampling signals and carrying out Hilbert transformation to obtain analysis signals of the sampling signals, ② determining window types, window lengths and window moving steps, ③ moving a window, calculating instantaneous autocorrelation of data in the window by taking a window center as a reference point, ④ carrying out fast Fourier transformation on the instantaneous autocorrelation, ⑤ moving the window by window moving steps and repeating the steps ③, ④ and ⑤ until all data are processed.

Further, the specific operation of distinguishing signals from different radar radiation sources by a signal sorting method based on QMF analysis is that the QMF analysis is adopted to realize orthogonal wavelet decomposition of the signals, the input signal energy is divided into orthogonal components in frequency by a dual-channel orthogonal mirror image filter bank, then the formed QMF pairs are introduced into a tree structure with a certain number of layers, the 'blocks' in each layer have the same area size by waveform decomposition, the output components of each filter are input into the QMF pairs in the next layer, each QMF pair decomposes the input signal waveform into two parts of high-frequency components and low-frequency components by taking pi as a boundary, and the 'blocks' refer to rectangular regions containing the energy of basis functions on a time-frequency plane. The quadrature mirror filter herein employs an improved SINC filter having a transfer function ofWherein N is more than or equal to (N-2)/2 and less than or equal to N/2, C is a compression variable, S is a scale variable, N is the number of convolution points, and omega (N) is a Hamming window function for inhibiting Gibbs phenomenon.

Furthermore, the matching of the radar radiation signal source and the interference signal is realized through a signal sorting method based on the rising edge waveform matching, and the method has the specific operations of ① extracting the pulse signal envelope and carrying out curve fitting, ② extracting the rising edge of the pulse signal envelope after the curve fitting, and ③ judging the similarity of the rising edge waveforms of the radar radiation source signal and the interference signal by adopting a Huasdorff distance method to complete the matching of the radar radiation signal source and the interference signal.

Further, signal similarity analysis is completed through waveform similarity measurement, and the method specifically comprises the steps of ① performing overall comparison on radar radiation source signals and interference signal waveforms by combining an included angle cosine algorithm and a sliding window algorithm to obtain waveform basic similarity, ② comparing amplitudes of the radar radiation source signal waveforms and the interference signal waveforms by adopting an average absolute difference algorithm to obtain amplitude similarity, and ③ performing average weighting on the waveform basic similarity and the amplitude similarity to obtain a final similarity value of the radar radiation source signal waveforms and the interference signal waveforms.

Furthermore, the evaluation standard of the interference effect evaluation result is that the interference effect is good when the final similarity value is more than 95%, the interference effect is general when 80% -95%, the critical interference is 65% -80%, and the interference effect is no more than 65%.

According to the method, the similarity analysis is carried out on the radar radiation source signal and the interference signal, the interference effect evaluation of the interference signal is given, a reference basis is provided for the actual operation judgment of combat training, and meanwhile effective technical support is provided for the interference decision of equipment operators.

Drawings

FIG. 1 is a flow chart of a method for evaluating interference effect of radar interference equipment;

FIG. 2 is a schematic flow chart of a ZFT frequency measurement method;

FIG. 3 shows the frequency k₀A nearby spectrum spread;

FIG. 4 is a flow chart of a WVD process;

FIG. 5 is a diagram of a quadrature mirror filterbank tree structure;

FIG. 6 is a contour plot of an L FM signal 5-level QMF analysis;

FIG. 7 is a contour plot of a Barker signal 3-layer QMF analysis;

FIG. 8 is a contour plot of costas signal 3-layer QMF analysis;

FIG. 9 is a contour plot of a 2-layer QMF analysis of the frank signal;

FIG. 10 is a waveform of a pulse envelope of a radar radiation source signal;

FIG. 11 is a flow chart of a method for sorting signals based on leading edge waveform pairing;

FIG. 12 is a diagram of a dynamic sliding window algorithm;

fig. 13 is a flow chart of a segmented FFT phase weighted frequency measurement method.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention have been presented for purposes of illustration and description, and are not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.