Intermittent sampling interference suppression method based on signal mask

Abstract

The invention discloses an intermittent sampling interference suppression method based on a signal mask. The method comprises the following steps: acquiring an echo signal; performing time domain threshold interference detection on the echo signal to obtain at least one time domain interference interval and an interference echo signal segment; frequency domain interference detection is carried out on the interference echo signal segments, and an interference frequency band corresponding to each interference echo signal segment is determined; performing correlation analysis on the interference echo signal segments and the radar transmitting signals, determining interference forwarding signal segments and interference sampling parameters thereof, and obtaining a target signal frequency band in a frequency spectrum of each interference echo signal segment; correcting the interference frequency band according to the target signal frequency band to obtain a corresponding corrected interference frequency band; and performing time domain and frequency domain combined suppression on the echo signal according to the corrected interference frequency band and the time domain interference interval to obtain an echo signal after interference suppression. According to the method, the intermittent sampling interference suppression effect can be effectively improved, and the calculation complexity is low.

Description

Technical Field

[0001] The present invention belongs to the field of radar technology, and in particular relates to an intermittent sampling interference suppression method based on a signal mask. Background Art

[0002] In complex electromagnetic confrontation scenarios, it is crucial to maintain the effective detection capability of radar systems. Radar jamming technology has undergone multiple stages of evolution, from primary means such as basic noise suppression and artificial jamming source deployment to a multi-faceted countermeasure system covering signal deception and complex jamming. Advanced jamming systems based on digital radio frequency storage technology can implement full pulse forwarding, intermittent sampling forwarding, and convolution modulation derivative modes through flexible signal sampling and reconstruction mechanisms. Specifically, intermittent sampling jamming includes three typical paradigms: (1) repeated forwarding jamming, which generates a main false target group through periodic sampling and multi-pulse repetition, but has the defect of insufficient signal correlation; (2) direct forwarding jamming, which uses discontinuous sampling to generate a mixed structure of main and secondary false targets, and the difference in its signal segments gives it higher target correlation; (3) cyclic forwarding jamming, which adopts a forward-reverse alternating forwarding strategy, continuing the signal slice cycle outside the pulse period, forming a dense jamming cloud of main and secondary false targets intertwined.

[0003] Currently, common intermittent sampling interference suppression methods mainly include three typical paradigms: time domain masking, frequency domain masking, and time-frequency domain masking. Among them, time domain masking achieves interference suppression by masking the interference region of the original echo. Frequency domain masking achieves interference suppression by performing a Fourier transform on the interference region and calculating the interference bandwidth as the frequency domain mask region. The time-frequency domain masking method obtains the time-frequency domain image of the echo signal by performing a short-time Fourier transform on the echo signal. Then, by estimating the parameters of the interference region, the time-frequency domain region to be masked is obtained, thereby achieving interference suppression.

[0004] In practice, when performing intermittent sampling interference suppression, the performance of time-domain masking methods is primarily affected by the interference's time-domain coverage. When time-domain coverage is high, target energy loss is significant, resulting in poor interference suppression. When using frequency-domain masking methods for interference suppression, the interference signal has high sidelobes in the frequency domain, so a significant amount of interference remains after masking, affecting the effectiveness of interference suppression. Furthermore, when using time-frequency domain masking methods for interference suppression, the high computational complexity of the short-time Fourier transform (SFT) results in poor real-time performance.

[0005] Therefore, there is an urgent need for an intermittent sampling interference suppression method with good interference suppression effect and low computational complexity. Summary of the Invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides an intermittent sampling interference suppression method based on a signal mask.

[0007] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0008] The present invention provides a method for suppressing intermittent sampling interference based on a signal mask, comprising:

[0009] Acquire echo signal;

[0010] Performing time domain threshold interference detection on the echo signal to obtain at least one time domain interference interval and a corresponding interference echo signal segment;

[0011] Performing frequency domain interference detection on each of the interference echo signal segments to determine an interference frequency band corresponding to each interference echo signal segment;

[0012] By performing correlation analysis on the interference echo signal segments and the radar transmission signal respectively, determining the interference forwarding signal segments and the interference sampling parameters of the interference forwarding signal segments, and obtaining the target signal frequency band in the spectrum corresponding to each interference echo signal segment according to the interference forwarding signal segments and the interference sampling parameters;

[0013] Correcting the interference frequency band according to the target signal frequency band to obtain a corrected interference frequency band corresponding to each interference echo signal segment;

[0014] The echo signal is jointly suppressed in the time domain and the frequency domain according to the corrected interference frequency band and the time domain interference interval.

[0015] Optionally, the method further includes:

[0016] Get background noise samples;

[0017] Calculating a threshold to be used in the time-domain threshold interference detection based on the background noise sample;

[0018] The calculation method of the threshold to be used in the time domain threshold interference detection is:

[0019] threshold=-P n log(P fa );

[0020] Among them, P n is the background noise power, P fa is the false alarm probability of interference detection, and threshold is the threshold to be used in time domain threshold interference detection.

[0021] Optionally, performing frequency domain interference detection on each interference echo signal segment to determine an interference frequency band corresponding to each interference echo signal segment includes:

[0022] Performing an equal number of point FFT transformations on the interference echo signal segments respectively to obtain a frequency spectrum corresponding to each interference echo signal segment;

[0023] According to the frequency domain threshold, the rising edge and the falling edge of the interference signal in the frequency spectrum corresponding to each interference echo signal segment are determined to obtain the interference frequency band corresponding to each interference echo signal segment.

[0024] Optionally, the performing joint suppression of the echo signal in the time domain and the frequency domain according to the corrected interference frequency band and the time domain interference interval includes:

[0025] Performing time domain masking on the echo signal according to the time domain interference interval to obtain a time domain mask signal;

[0026] Performing frequency domain masking on the echo signal of each time domain interference interval according to the corrected interference frequency band to obtain a frequency domain mask signal corresponding to the time domain interference interval;

[0027] The frequency domain mask signal corresponding to each time domain interference interval is used to replace the signal in the time domain interference interval in the time domain mask signal, thereby achieving joint suppression of the echo signal in the time domain and frequency domain.

[0028] Optionally, determining the interference forwarding signal segment and the interference sampling parameter of the interference forwarding signal segment by performing correlation analysis on the interference echo signal segment and the radar transmit signal respectively includes:

[0029] The interference repeater signal segment and the interference sampling parameter of the interference repeater signal segment are determined by respectively calculating the Pearson correlation coefficient of the interference echo signal segment and the radar transmission signal.

[0030] The intermittent sampling interference suppression method based on signal mask provided by the present invention first performs time domain threshold interference detection on the echo signal to obtain at least one time domain interference interval and a corresponding interference echo signal segment; then, frequency domain interference detection is performed on each interference echo signal segment to obtain an interference frequency band; then, by performing correlation analysis on the interference echo signal segment and the transmitted signal respectively, each interference forwarding signal segment and interference sampling parameter are obtained to obtain the target signal frequency band, and then the interference frequency band is corrected according to the target signal frequency band to obtain a more accurate corrected interference frequency band; finally, according to the corrected interference frequency band and the time domain interference interval, the echo signal is jointly suppressed in the time domain and frequency domain to achieve interference suppression of the echo signal. The present invention performs joint suppression in the time domain and frequency domain based on the time domain information and frequency domain information of the echo signal, which makes up for the defect that the real target echo signal is lost when interference suppression is performed in a single time domain or a single frequency domain. Moreover, compared with the time-frequency domain interference suppression algorithm, the present invention has lower computational complexity. Therefore, the present invention greatly improves the intermittent sampling interference suppression effect and has higher computational efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 1 is a flow chart of a method for suppressing intermittent sampling interference based on a signal mask provided by an embodiment of the present invention;

[0032] Figure 2 1 is a schematic diagram of a framework flow of a method for suppressing intermittent sampling interference based on a signal mask provided by an embodiment of the present invention;

[0033] Figure 3 This is a comparison diagram of pulse pressure after interference suppression using the intermittent sampling interference suppression method based on signal mask provided by an embodiment of the present invention and the existing time domain mask algorithm;

[0034] Figure 4 This is a comparison diagram of pulse pressure after interference suppression between the intermittent sampling interference suppression method based on signal mask provided by an embodiment of the present invention and the existing frequency domain mask algorithm. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below with reference to specific examples, but the embodiments of the present invention are not limited thereto.

[0036] In order to achieve better intermittent sampling interference suppression effect and higher computational efficiency, the embodiment of the present invention provides an intermittent sampling interference suppression method based on a signal mask, see Figure 1 and Figure 2 , the method comprises the following steps:

[0037] S10. Acquire an echo signal.

[0038] Specifically, an echo signal refers to the electromagnetic wave signal emitted by the radar, which is reflected by the target and received by the radar system after encountering it. When intermittent sampling jammers are present, the echo signal received by the radar system contains the transmitted signal fragment sampled and forwarded by the intermittent sampling jammer, as well as the target echo signal.

[0039] In this step, after the echo signal is acquired, it can be discretized in time and converted into a series of discrete sampling points for digital signal processing. Specifically, the acquired echo signal is sampled and processed according to the sampling rate fs and sampling gate width set by the radar system. The discretized echo signal data can be expressed as:

[0040]

[0041] Among them, N L Indicates the number of sampling points of the echo signal, x l Indicates the first l=[1,2,...,N L ] sampling points echo signal data.

[0042] S20: Perform time-domain threshold interference detection on the echo signal to obtain at least one time-domain interference interval and a corresponding interference echo signal segment.

[0043] Among them, time domain threshold interference detection is a method that detects the time domain interval where the interference is located based on the threshold and the echo signal energy.

[0044] Exemplarily, the threshold to be used in time-domain threshold interference detection can be obtained by the following method:

[0045] (1) Obtain background noise samples.

[0046] For example, the background noise sample can be an echo signal received by the radar system that contains only pure noise signals. In this case, the pure noise signal received by the radar system is sampled and processed with the same sampling rate fs and sampling gate width as in step S10 to obtain discretized background noise signal data:

[0047]

[0048] Among them, M L Represents the number of sampling points of the background noise signal, n l Represents the background noise signal data of the lth sampling point.

[0049] (2) Based on the background noise samples, calculate the threshold to be used in time domain threshold interference detection.

[0050] Here, based on the discretized background noise signal data, the background noise power P can be calculated. n , thereby calculating the threshold to be used in time domain threshold interference detection.

[0051] In this embodiment, the threshold to be used in time-domain threshold interference detection is calculated as follows:

[0052] threshold=-P n log(P fa );

[0053] Among them, P n is the background noise power, P fa is the false alarm probability of interference detection, and threshold is the threshold to be used in time-domain threshold interference detection. Here, the false alarm probability of interference detection is an empirical value pre-calculated based on the interference-to-noise ratio of the echo signal received by the radar system.

[0054] The specific implementation process of time-domain threshold interference detection is as follows: the echo signal energy of each sampling point is calculated and compared with the threshold. When the echo signal energy of each sampling point is greater than the threshold, the echo signal at that sampling point is considered to be interfered with. Then, by marking each sampling point (for example, by binarizing each sampling point in the echo signal), M time-domain interference intervals affected by interference and M interference echo signal segments corresponding to these M time-domain interference intervals are obtained. M ≥ 1.

[0055] S30: Perform frequency domain interference detection on each interference echo signal segment to determine an interference frequency band corresponding to each interference echo signal segment.

[0056] Here, frequency domain interference detection is performed on each of the M interference echo signal segments obtained in step S20, so as to determine the interference frequency band corresponding to each interference echo signal segment.

[0057] Specifically, frequency domain interference detection is performed on each interference echo signal segment to determine the interference frequency band corresponding to each interference echo signal segment, including:

[0058] (1) For each interference echo signal segment, perform an equal number of point FFT transformation on the interference echo signal segment to obtain the frequency spectrum corresponding to the interference echo signal segment.

[0059] Specifically, an equal number of point FFT transformation is performed on each interference echo signal segment, thereby obtaining the spectrum corresponding to each interference echo signal segment. n When the interference echo signal segment is preprocessed to make its length meet 2 n , and then perform fast Fourier transform on the interference echo signal segment to obtain the spectrum corresponding to the interference echo signal.

[0060] Here, the manner of performing FFT transformation of equal number of points on the interference echo signal segments can be referred to the relevant prior art, which will not be described in detail here.

[0061] (2) For each interference echo signal segment, the rising edge and the falling edge of the interference signal in the frequency spectrum corresponding to the interference echo signal segment are determined according to the frequency domain threshold to obtain the interference frequency band corresponding to the interference echo signal segment.

[0062] Here, the frequency domain threshold is a threshold used when performing interference detection in the frequency domain to determine the interference frequency band. Exemplarily, a method for calculating the frequency domain threshold is:

[0063] threshold f =-P nf log(Pfa );

[0064] Among them, P nf is the background noise power in the frequency domain, P fa is the false alarm probability of interference detection, threshold f The frequency domain threshold used for interference detection in the frequency domain.

[0065] Here, the frequency domain background noise power P nf The obtained value can be obtained by performing an equal number of point FFT transformation on the discretized background noise signal data obtained in step S20 and then calculating the value based on the frequency spectrum corresponding to the background noise signal.

[0066] Therefore, the frequency points in the spectrum corresponding to the interference echo signal segment are traversed respectively. During the traversal, the rising edge and falling edge of the interference signal in the spectrum corresponding to the interference echo signal segment are determined according to the calculated frequency domain threshold, and the interference frequency band corresponding to the interference echo signal segment can be obtained.

[0067] Exemplarily, in one implementation, based on the calculated frequency domain threshold, the rising edge and falling edge of the interference signal in the spectrum corresponding to the interference echo signal segment are determined. This can be achieved using a rising edge flag. Specifically, the rising edge flag is first set to 0, and then the frequency points in the spectrum corresponding to the interference echo signal segment are traversed. During the traversal process, if the spectrum energy of the frequency point is detected to be greater than or equal to the frequency domain threshold or the spectrum energy changes from less than the frequency domain threshold to greater than or equal to the frequency domain threshold, a rising edge is determined to have occurred, and the rising edge flag is set to 1. Then, the traversal continues to search for a falling edge. If the spectrum energy of the frequency point is detected to change from greater than or equal to the frequency domain threshold to less than the frequency domain threshold, a falling edge is determined to have occurred. The frequency band between the rising edge and the falling edge is recorded as the interference frequency band, and the rising edge flag is reset to 0. The above process is repeated until the spectrum corresponding to the interference echo signal segment is traversed. If only a rising edge is detected and no falling edge is detected during the traversal process, the end of the spectrum is taken as the falling edge, and the frequency band between the rising edge and the falling edge is recorded as the interference frequency band.

[0068] Finally, through this step, the interference frequency band corresponding to each interference echo signal segment obtained in step S20 can be obtained.

[0069] S40. Determine the interference forwarding signal segment and the interference sampling parameters of the interference forwarding signal segment by performing correlation analysis on the interference echo signal segment and the radar transmission signal respectively, and obtain the target signal frequency band in the spectrum corresponding to each interference echo signal segment according to the interference forwarding signal segment and the interference sampling parameters.

[0070] In this embodiment, the interference forwarding signal segment and the interference sampling parameters of the interference forwarding signal segment are determined by performing correlation analysis on the interference echo signal segment and the radar transmission signal respectively, including: determining the interference forwarding signal segment and the interference sampling parameters of the interference forwarding signal segment by calculating the Pearson correlation coefficient of the interference echo signal segment and the radar transmission signal respectively.

[0071] Here, the Pearson correlation coefficient is calculated as:

[0072]

[0073] Where, s is the transmitted signal segment representing the radar transmitted signal, j is the interference echo signal segment, k is the number of sampling points of the interference echo signal segment, t is the sliding window starting position identifier for calculating the Pearson correlation coefficient, and s t+i is the i-th sampling point data of the transmitted signal segment, j i is the i-th sampling point data of the interference echo signal segment, is the mean value of the sampling point data of the transmitted signal segment, is the mean value of the sampling point data of the interference echo signal segment.

[0074] A correlation analysis is performed on the interference echo signal segment and the radar transmission signal to determine the interference forwarding signal segment and the interference sampling parameters of the interference forwarding signal segment. Specifically, when the interference echo signal segment contains k sampling points, a sliding window with a window length of k sampling points and a step of 1 is set. The transmission signal segment is traversed using the sliding window, and the Pearson correlation coefficients of the interference echo signal segment and the transmission signal segments within the sliding window are sequentially calculated to obtain the sliding window position corresponding to the maximum Pearson correlation coefficient. Therefore, the transmission signal at this sliding window position is the interference forwarding signal segment. At the same time, based on the interference forwarding signal segment, it can be determined that the starting sampling point position of the sliding window position is the interference sampling starting position of the interference forwarding signal segment, and the sliding window length k is the interference sampling length of the interference forwarding signal segment. In other words, based on the interference forwarding signal segment, the interference sampling parameters of the interference forwarding signal segment are obtained.

[0075] Then, based on the interference forwarding signal segments and the interference sampling parameters, the target signal frequency band in the spectrum corresponding to each interference echo signal segment is obtained, including: assuming that the starting sampling point of the sliding window corresponding to the maximum Pearson correlation coefficient is the oth sampling point of the transmitted signal, the interference forwarding signal segment is the signal segment from the oth sampling point to the o+k-1th sampling point of the transmitted signal. Based on the sampling rate fs set by the radar system, it can be known that the interference forwarding signal segment is the signal segment of the transmitted signal within the time interval [o / fs, (o+k-1) / fs]. Therefore, it can be known that the target signal frequency band in the spectrum corresponding to the interference echo signal segment is the frequency band corresponding to the signal segment of the transmitted signal within the time interval [(o+k) / fs, (o+k+r*k-1) / fs], where r is the number of intermittent sampling interference forwarding.

[0076] It is understandable that the target signal may or may not exist in the spectrum corresponding to each interference echo signal segment. Therefore, when calculating the target signal frequency band using the above method, it is also necessary to check the signal amplitude in the calculated target signal frequency band in combination with the spectrum corresponding to the interference echo signal segment to finally determine whether the target signal frequency band actually corresponds to a real target.

[0077] S50 , correcting the interference frequency band according to the target signal frequency band to obtain a corrected interference frequency band corresponding to each interference echo signal segment.

[0078] Generally, interference signals generate significant sidelobe levels in the frequency domain. Applying frequency-domain mask suppression only to the detected mainlobe region will result in significant residual interference components. To address this, the present invention expands the interference frequency band corresponding to each detected interference echo signal segment to maximize interference signal suppression while ensuring the energy integrity of the target signal.

[0079] Specifically, for each interference echo signal segment corresponding to the interference frequency band, the target signal frequency band corresponding to the interference echo signal segment is used to correct it, and the frequency range of the interference frequency band corresponding to the interference echo signal segment is expanded to both ends to ensure that the target signal frequency band is complete, thereby obtaining a corrected interference frequency band with a wider frequency range.

[0080] S60: Perform joint suppression in the time domain and frequency domain on the echo signal according to the corrected interference frequency band and time domain interference interval.

[0081] In this embodiment, based on the modified interference frequency band and time domain interference interval, the echo signal is jointly suppressed in the time domain and frequency domain, specifically including:

[0082] (a) Perform time domain masking on the echo signal according to the time domain interference interval to obtain the time domain mask signal.

[0083] Specifically, according to the M time domain interference intervals obtained in step S20, the echo signal is time-domain masked so that the echo signals in the M time domain interference intervals are set to zero, thereby achieving time domain interference suppression. Here, the specific implementation of the time domain mask can be found in the relevant prior art and will not be described here in detail.

[0084] (b) According to the corrected interference frequency band, the echo signal of each time domain interference interval is frequency-domain masked to obtain the frequency-domain mask signal corresponding to the time domain interference interval.

[0085] Specifically, for the echo signal of each time domain interference interval, it is first converted to the frequency domain to obtain the frequency spectrum corresponding to the echo signal of the time domain interference interval, and then the frequency spectrum corresponding to the echo signal of the time domain interference interval is frequency-domain masked according to the corrected interference frequency band corresponding to the time domain interference interval, and then the frequency-domain masked spectrum is inverse Fourier transformed to obtain the frequency domain mask signal corresponding to the time domain interference interval.

[0086] Here, the specific implementation of the frequency domain mask can be found in the relevant existing technology and will not be described in detail here.

[0087] (c) The frequency domain mask signal corresponding to each time domain interference interval is used to replace the signal within the time domain interference interval in the time domain mask signal, thereby achieving joint suppression of the echo signal in the time domain and frequency domain.

[0088] Here, the time domain mask signal includes M time domain interference intervals. The signal of each time domain interference interval is replaced by the frequency domain mask signal corresponding to the time domain interference interval. After the replacement, the echo signal after interference suppression can be obtained.

[0089] The intermittent sampling interference suppression method based on signal mask provided by the present invention first performs time domain threshold interference detection on the echo signal to obtain at least one time domain interference interval and a corresponding interference echo signal segment; then, frequency domain interference detection is performed on each interference echo signal segment to obtain an interference frequency band; then, by performing correlation analysis on the interference echo signal segment and the transmitted signal respectively, each interference forwarding signal segment and interference sampling parameter are obtained to obtain the target signal frequency band, and then the interference frequency band is corrected according to the target signal frequency band to obtain a more accurate corrected interference frequency band; finally, according to the corrected interference frequency band and the time domain interference interval, the echo signal is jointly suppressed in the time domain and frequency domain to achieve interference suppression of the echo signal. The present invention performs joint suppression in the time domain and frequency domain based on the time domain information and frequency domain information of the echo signal, which makes up for the defect that the real target echo signal is lost when interference suppression is performed in a single time domain or a single frequency domain. Moreover, compared with the time-frequency domain interference suppression algorithm, the present invention has lower computational complexity. Therefore, the present invention greatly improves the intermittent sampling interference suppression effect and has higher computational efficiency.

[0090] The intermittent sampling interference suppression method based on signal mask provided by the present invention is further illustrated below through simulation experiments.

[0091] The following simulation experiment uses the energy of the echo signal as the training sample and 1000 intermittently sampled interference echo signals as the test sample. The hardware platform is: Intel Core i7-8700 CPU @ 3.2GHz 3.19GHz 16GB RAM, software platform: MATLAB.

[0092] Simulation 1: Under the conditions of -10dB signal-to-noise ratio, 20dB interference-to-noise ratio, and intermittent sampling interference (sampling one to two), the interference suppression effect of the method of the present invention is compared with that of the existing time domain mask algorithm. Figure 3 The following table shows the pulse pressure diagrams after interference suppression using the two methods, with the horizontal axis representing the number of range cells and the vertical axis representing the echo pulse pressure amplitude after interference suppression. The following table shows the improvement in the echo signal-to-interference-noise ratio (SIN) after interference suppression using the two methods. This shows that the method of the present invention significantly outperforms existing time-domain masking algorithms.

[0093] Existing time domain masking algorithms Method of the present invention Improved signal-to-interference-and-noise ratio 27.9dB 33.3dB

[0094] Simulation 2: Under the conditions of -10dB signal-to-noise ratio, 20dB interference-to-noise ratio, and intermittent sampling interference (sampling one to two), the interference suppression effects of the method of the present invention and the existing frequency domain mask algorithm are compared. Figure 4 The following table shows the pulse pressure diagrams after interference suppression using the two methods, with the horizontal axis representing the number of range cells and the vertical axis representing the echo pulse pressure amplitude after interference suppression. The following table shows the improvement in the echo signal-to-interference-noise ratio (SIN) after interference suppression using the two methods. This shows that the method of the present invention significantly outperforms existing frequency domain masking algorithms.

[0095] Existing frequency domain masking algorithms Method of the present invention Improved signal-to-interference-and-noise ratio 10.7dB 33.3dB

[0096] In simulation three, when the echo signal-to-noise ratio is -10 dB, the interference-to-noise ratio of the echo signal is randomly selected from [10, 11, …, 15], and the interference type is intermittent sampling interference (sampling one to two), the interference suppression effect of the algorithm of the present invention is analyzed as it changes with the echo signal interference-to-noise ratio. As can be seen from the table below, the larger the echo signal interference-to-noise ratio, the better the interference suppression effect of the present invention.

[0097]

[0098] It should be noted that the terms "first," "second," and the like are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in sequences other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention.

[0099] In the description of this specification, the reference terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0100] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art can understand and implement other variations of the disclosed embodiments by viewing the drawings and the disclosed content. In the description of the present invention, the word "comprising" does not exclude other components or steps, "one" or "a" does not exclude multiple situations, and "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, certain measures are recorded in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0101] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A method for suppressing intermittent sampling interference based on a signal mask, characterized in that: include: Acquire echo signal; Performing time domain threshold interference detection on the echo signal to obtain at least one time domain interference interval and a corresponding interference echo signal segment; Performing frequency domain interference detection on each of the interference echo signal segments to determine an interference frequency band corresponding to each interference echo signal segment; By performing correlation analysis on the interference echo signal segments and the radar transmission signal respectively, determining the interference forwarding signal segments and the interference sampling parameters of the interference forwarding signal segments, and obtaining the target signal frequency band in the spectrum corresponding to each interference echo signal segment according to the interference forwarding signal segments and the interference sampling parameters; Correcting the interference frequency band according to the target signal frequency band to obtain a corrected interference frequency band corresponding to each interference echo signal segment; The echo signal is jointly suppressed in the time domain and the frequency domain according to the corrected interference frequency band and the time domain interference interval.

2. The intermittent sampling interference suppression method based on signal mask according to claim 1, characterized in that: The method further comprises: Get background noise samples; Calculating a threshold to be used in the time-domain threshold interference detection based on the background noise sample; The calculation method of the threshold to be used in the time domain threshold interference detection is: threshold=-P n log(P fa ); Among them, P n is the background noise power, P fa is the false alarm probability of interference detection, and threshold is the threshold to be used in time domain threshold interference detection.

3. The intermittent sampling interference suppression method based on signal mask according to claim 1, characterized in that: The performing frequency domain interference detection on each of the interference echo signal segments to determine an interference frequency band corresponding to each interference echo signal segment includes: Performing an equal number of point FFT transformations on the interference echo signal segments respectively to obtain a frequency spectrum corresponding to each interference echo signal segment; According to the frequency domain threshold, the rising edge and the falling edge of the interference signal in the frequency spectrum corresponding to each interference echo signal segment are determined to obtain the interference frequency band corresponding to each interference echo signal segment.

4. The intermittent sampling interference suppression method based on signal mask according to claim 1, characterized in that: The performing time-domain and frequency-domain joint suppression on the echo signal according to the corrected interference frequency band and the time-domain interference interval includes: Performing time domain masking on the echo signal according to the time domain interference interval to obtain a time domain mask signal; Performing frequency domain masking on the echo signal of each time domain interference interval according to the corrected interference frequency band to obtain a frequency domain mask signal corresponding to the time domain interference interval; The frequency domain mask signal corresponding to each time domain interference interval is used to replace the signal in the time domain interference interval in the time domain mask signal, thereby achieving joint suppression of the echo signal in the time domain and frequency domain.

5. The intermittent sampling interference suppression method based on signal mask according to claim 1, characterized in that: The determining of the interference forwarding signal segment and the interference sampling parameter of the interference forwarding signal segment by respectively performing correlation analysis on the interference echo signal segment and the radar transmission signal includes: The interference repeater signal segment and the interference sampling parameter of the interference repeater signal segment are determined by respectively calculating the Pearson correlation coefficient of the interference echo signal segment and the radar transmission signal.

Images