Method for eliminating influence of pulse interference on radar echo frequency domain characteristics

Abstract

The invention discloses a method for eliminating the influence of pulse interference on radar echo frequency domain characteristics, and relates to the technical field of pulse interference elimination, and the method comprises the steps: obtaining a radar echo signal without pulse interference, and carrying out the preprocessing, and obtaining a power spectrum density sequence of the echo signal in each distance unit; based on the power value intensity, the power spectral density sequence is arranged in an ascending order; carrying out integration processing on the power spectrum sequence after ascending arrangement from low to high; determining a total power interval for the power spectrum sequence after integration processing, and calculating a noise level, namely a noise level without pulse interference; and processing a radar echo signal to be processed by using the property that an echo signal with pulse interference approximately superposes an impulse signal on an echo signal without pulse interference to obtain an increment level corresponding to the interference and eliminate the increment level, thereby completing pulse interference elimination processing on the echo signal with pulse interference. The method can effectively eliminate the influence of pulse interference on the frequency domain characteristic of the radar echo signal.

Description

Technical Field

[0001] The present invention relates to the technical field of pulse interference elimination, and in particular to a method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echoes. Background Art

[0002] Radar data processing refers to the process of processing and analyzing the raw signals received by the radar system. The purpose is to extract valuable information, identify target characteristics, track target movement, and ultimately support decision-making or control. It is the core link in radar technology and is widely used in military, aviation, meteorology, navigation and other fields.

[0003] At present, domestic radar data processing mostly relies on radar manufacturers. However, due to limited conditions, efforts in data quality control are mainly limited to radar signal processing and data processing, and the methods used are relatively conventional, which can only reduce data errors caused by a small part of clutter. However, research on the impact of noise (pulse interference) on the frequency domain characteristics of radar signals is still relatively blank, and the impact of noise (pulse interference) on frequency domain characteristics cannot be truly eliminated. Summary of the Invention

[0004] In view of this, the present application provides a method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echoes, so as to eliminate the influence of noise (pulse interference) on the frequency domain characteristics.

[0005] In a first aspect, the present application provides a method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echoes, comprising: Obtain the radar echo signal without pulse interference and preprocess it to obtain the power spectrum sequence of each range unit; Arranging the power spectrum sequence in ascending order based on power value intensity; The power spectrum sequence after ascending order is integrated from low to high; For the power spectrum sequence after the integration process, a total power interval is determined, which is recorded as a first total power interval; In the first total power interval, based on the maximum total power value And the corresponding spectrum points calculate the mean power to obtain the noise level corresponding to the radar echo signal without pulse interference ; Set the signal / clutter level threshold and the impulse interference noise level threshold; Obtaining a total power interval of the radar echo signal to be processed, recorded as a second total power interval; calculating, outside the second total power interval, a difference between the total power of each spectrum point and the maximum total power value within the second total power interval, and determining, when the difference exceeds the signal / clutter level threshold, that the corresponding spectrum point is a signal or a clutter level signal; In the second total power interval, the noise level of each spectrum point in the corresponding power spectrum sequence is the noise level of the radar echo signal without pulse interference. Incremental level corresponding to pulse interference signal When the noise level estimated in the second total power interval and the noise level corresponding to the radar echo signal without pulse interference are superimposed, When the difference exceeds the pulse interference noise level threshold, the radar echo signal to be processed is determined to be an echo signal containing pulse interference, and the corresponding difference is the incremental level corresponding to the pulse interference signal. ; The noise level signal containing pulse interference is processed to eliminate the pulse interference noise.

[0006] In a possible implementation of the first aspect, performing integration processing on the power spectrum arranged in ascending order from low to high includes: Arrange in ascending order The power value of each spectrum point, Sort in ascending order The sum of the power values of the spectrum points.

[0007] In a possible implementation of the first aspect, determining the total power interval for the power spectrum sequence after integration includes: After integrating the power spectrum sequence from low to high, set the upper and lower power limits. When the power value of a spectrum point in the power spectrum sequence after integration is between the lower and upper power limits, determine the corresponding total power interval, and the corresponding spectrum point number is , is the spectrum point number corresponding to the upper limit power value, is the spectrum point number corresponding to the lower limit power value.

[0008] In a possible implementation of the first aspect, when there is no pulse interference, the maximum total power value is determined within the first total power interval. include: is the total power value of the spectrum point with the maximum power in the total power interval, is the serial number corresponding to the spectrum point.

[0009] In a possible implementation of the first aspect, based on the maximum total power value and the corresponding spectrum points to calculate the noise level include: .

[0010] In a possible implementation of the first aspect, acquiring the impulse interference noise level threshold includes: is the impulse interference noise level threshold.

[0011] In a possible implementation of the first aspect, the method further includes: Outside the total power interval, calculate the total power of each spectrum point and the maximum total power value in the total power interval The difference of is used to obtain the difference set; Obtaining a minimum value among the differences corresponding to the difference value set that exceeds the signal / clutter level threshold, and obtaining a corresponding spectrum point as a first spectrum point; The power value of the first spectrum point is used as the upper limit power value.

[0012] In a possible implementation of the first aspect, the method further includes: When the noise level estimated in the second total power interval is equal to the noise level corresponding to the radar echo signal without pulse interference The difference exceeds the impulse noise level threshold When the radar echo signal to be processed is determined to be an echo signal containing pulse interference, the corresponding difference is the pulse interference signal Corresponding interference level .

[0013] In a possible implementation of the first aspect, performing pulse interference noise elimination processing on the noise level signal containing pulse interference includes: is a frequency domain noise signal without pulse interference, is a frequency domain noise signal containing pulse interference, is the frequency domain signal of pulse interference; is a pulse interference signal, Represents the time shift of the time series, which is a non-negative integer; is the impulse signal amplitude, is a unit impulse signal; To perform discrete Fourier transform on the actual pulse interference signal.

[0014] In a possible implementation of the first aspect, the method further includes: To perform discrete Fourier transform on noise level signal containing impulse interference; is the number of discrete Fourier transform points.

[0015] The beneficial effects of the present invention are as follows: the present invention discloses a method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echoes. By obtaining a radar echo signal without pulse interference and performing preprocessing, a power spectrum density sequence of the echo signal in each distance unit is obtained; based on the power value intensity, the power spectrum density sequence is sorted in ascending order; the power spectrum sequence after ascending order is integrated from low to high; for the power spectrum sequence after integration, a total power interval is determined, and a noise level is calculated, that is, the noise level without pulse interference; and a signal / clutter level threshold and a noise level threshold with pulse interference are set. Outside the total power interval, the difference between the total power of each spectrum point and the maximum power in the total power interval is calculated. When the power difference exceeds the signal / clutter level threshold, the spectrum point is determined to be a signal or a clutter level signal. Within the total power interval, when pulse interference exists, the characteristic that the pulse interference signal is similar to an impulse signal is utilized, and the power spectrum density sequence of the radar echo signal containing pulse interference is the superposition of the power of the echo signal without pulse interference and the power of the pulse interference signal at each spectral point. At this time, the noise level determined by the above steps will raise the interference level corresponding to the pulse interference signal. When the incremental level exceeds the noise level threshold with pulse interference, the radar echo signal at this time is determined to be an echo signal containing pulse interference. The calculated incremental level is the interference level corresponding to the pulse interference signal. By eliminating this interference level, the pulse interference elimination processing of the echo signal containing pulse interference can be completed. The present invention provides a method for estimating noise level power in the frequency domain. Based on this method, the incremental noise level corresponding to the pulse interference signal is estimated by comparing the noise levels with and without pulse interference levels, and pulse interference noise elimination processing is performed, which can effectively eliminate the influence of pulse interference on the frequency domain characteristics of the radar echo signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0017] Figure 1 This is a flow chart of a method for eliminating the influence of pulse interference on frequency domain characteristics provided by an embodiment of the present application; Figure 2 Schematic diagram of the power spectrum of the echo signal without pulse interference after integration processing provided in an embodiment of the present application; Figure 3 This is a schematic diagram of the power spectrum of an echo signal with pulse interference after integration processing provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0019] In this application, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0020] Example In existing technologies, Zhu Bin and other researchers have conducted in-depth research on wind profiler radar power spectrum data. They applied the principle of symmetry to eliminate intermittent clutter and further improved data quality by comparing the consistency of turbulent target peaks above and below, as well as before and after. In 2013, He Ping et al. innovatively proposed a new method for calculating the noise level of wind profiler radar power spectra based on wind profiler radar power spectrum estimation methods and the frequency domain characteristics of noise. In 2009, Yang Xinrui proposed a strategy for optimizing wind profiler radar data quality using Kalman filtering. Although this method is significantly affected by the model, it laid an important foundation for subsequent improvements and optimization of quality control models. In 2011, Zhang Wenwen et al. proposed a method using the lifting static wavelet transform to effectively suppress ground clutter in wind profiler radar data. In 2016, Liu Cheng applied wavelet transform methods to denoise and suppress wind profiler power spectrum data, and successfully implemented Gaussian curve fitting of wind spectrum data using the LM algorithm. At the same time, Zhang Xubin and Li Lei combined the EOF (empirical orthogonal function) and Gaussian filtering methods to conduct comprehensive quality control of the wind field data of the wind profiler radar. The vertical detection beam data of the wind profiler radar plays an important role in revealing the fine information of the vertical structure of precipitation clouds. In 2020, Xing Fenghua and others carried out a detailed classification of precipitation clouds based on parameters such as echo intensity, vertical velocity, and velocity spectrum width in the wind profiler radar data. Chen Zhongyu and others calculated the median of the horizontal wind and constructed a difference sequence with the actual wind field, thereby achieving effective control of the horizontal wind. In 2021, Chen Xia and others proposed a comprehensive quality control method that integrates multiple technical means, including spectral peak search and consistency averaging, to deal with different types of clutter interference. In addition, Ruan Feng and others also explored the integrated application of wind profiler radar and weather radar, and proposed a novel method for data calibration using only the power spectrum of the wind profiler radar return signal.

[0021] Currently, the main international research results in this field are summarized as follows: Wind speed values calculated from data during precipitation often exhibit significant deviations, therefore precipitation is considered a key interfering factor that must be eliminated. Ecklund et al. evaluated the magnitude of vertical radial velocity to determine whether precipitation occurred in a specific area at a specific time. Steiner et al. constructed a function to determine whether data were affected by precipitation by analyzing the differences between the zeroth, first, and second moments of the sounding signal and their estimated values under clear weather conditions. In 2004, Robert et al. introduced the coplanar spectral averaging (CSA) technique. This technique integrates the temporal variations of coplanar spectra in the east-west or north-south directions into an array and then processes the spectrum using a mean or median filter. Japan has implemented a two-tiered quality control approach: initial quality control at the station, followed by consistency verification on a central computer, to improve data quality. Because median filtering can assess the spatiotemporal continuity of wind, it is also widely used in quality control. Specifically, the u and v components of the horizontal wind at a given point in time and space are compared with the median of the u and v components observed at nearby points in time and space. If the difference between the two exceeds a threshold proposed by Winifred, the horizontal wind is marked. Holleman proposed that using volume velocity processing (VVP) can more accurately obtain wind profile information than velocity azimuth display. In 2012, Lehmann proposed a new statistical filtering algorithm based on simultaneous time-frequency analysis to address the interference caused by bird flight. In 2014, Wilfong proposed a method using the median to determine noise power. In 2015, Allabakash et al. proposed applying a wavelet transform to I / Q data to suppress interference from ground clutter. In 2018, Lehmann et al. further expanded on this idea, using a wavelet transform to process I / Q data, effectively suppressing the negative impact of various clutter on the power spectrum data.

[0022] At present, the processing of radar data in China mostly relies on radar manufacturers. However, due to limited conditions, efforts in quantity and quality control are mainly limited to conventional radar signal processing and data processing, and the methods used are relatively conventional, which can only reduce the data errors caused by a small part of the clutter. Domestic research on the impact of noise interference on frequency domain characteristics is still relatively blank, and the impact of noise (pulse interference) on frequency domain characteristics cannot be truly eliminated.

[0023] Therefore, the present application provides a method for eliminating the influence of pulse interference on frequency domain characteristics, such as Figure 1 Shown, including: Obtain the radar echo signal without pulse interference and preprocess it to obtain the power spectrum sequence of each range unit; Arranging the power spectrum sequence in ascending order based on power value intensity; The power spectrum sequence after ascending order is integrated from low to high; For the power spectrum sequence after the integration process, a total power interval is determined, which is recorded as a first total power interval; In the first total power interval, based on the maximum total power value And the corresponding spectrum points calculate the mean power to obtain the noise level corresponding to the radar echo signal without pulse interference ; Set the signal / clutter level threshold and the impulse interference noise level threshold; Obtaining a total power interval of the radar echo signal to be processed, recorded as a second total power interval; calculating, outside the second total power interval, a difference between the total power of each spectrum point and the maximum total power value within the second total power interval, and determining, when the difference exceeds the signal / clutter level threshold, that the corresponding spectrum point is a signal or a clutter level signal; In the second total power interval, the noise level of each spectrum point in the corresponding power spectrum sequence is the noise level of the radar echo signal without pulse interference. Incremental level corresponding to pulse interference signal When the pulse interference signal corresponds to the incremental level When the noise level exceeds the pulse interference noise level threshold, the radar echo signal is determined to be a noise level signal containing pulse interference; The noise level signal containing pulse interference is processed to eliminate the pulse interference noise.

[0024] Among them, the power spectrum of the radar signal reflects the power distribution of the signal in different frequency components and is an important tool for analyzing radar signals. Preprocessing of the radar signal includes signal acquisition, DC component removal, windowing processing, and high-frequency and low-frequency filtering. Then, the classic power spectrum estimation method or parameterized power spectrum estimation method is used to obtain the power spectrum sequence.

[0025] The power spectrum sequence is arranged in ascending order based on the power value intensity, that is, the power values of the power spectrum are arranged in ascending order.

[0026] Among them, the power spectrum after being arranged in ascending order is integrated from low to high, including: The purpose is to facilitate the subsequent distinction of the power spectrum after ascending order into the normal level interval, noise level interval and signal / clutter level interval. The power spectrum after integration processing is as follows: Figure 2 shown.

[0027] Among them, for the power spectrum after integration processing, the total power range is determined, that is, by setting the upper limit power value and the lower limit power value, when the power value of the spectrum point in the power spectrum after integration processing is between the lower limit power value and the upper limit power value, the total power range is determined. Optionally, the total power range is 5%~40%.

[0028] The upper limit power value of the total power interval is obtained by calculating the total power of each spectrum point outside the total power interval and the maximum total power value within the total power interval. obtain a difference set; obtain the minimum value among the differences corresponding to the signal / interference level threshold in the difference set, and obtain the corresponding spectrum point as the first spectrum point; use the power value of the first spectrum point as the upper limit power value, and further determine the total power interval range.

[0029] In the second total power interval, the noise power level is calculated. When pulse interference exists, the characteristic that the pulse interference signal is similar to the impulse signal is used. The power at each spectrum point in the power spectrum density sequence of the radar echo signal containing pulse interference is the superposition of the echo signal power without pulse interference and the power of the pulse interference signal. The power spectrum after integration is as follows: Figure 3 As shown, the incremental level corresponding to the pulse interference signal is estimated by comparing the noise level with and without the pulse interference level. , when the incremental level Exceeds the set pulse interference noise level threshold (such as 1dB), , it is determined that the radar echo signal at this time is an echo signal containing pulse interference, and the calculated incremental level That is the pulse interference signal The corresponding interference level.

[0030] The step of performing pulse interference noise elimination processing on the noise level signal containing pulse interference includes: is a frequency domain noise signal without pulse interference, is a frequency domain noise signal containing pulse interference, is the frequency domain signal of pulse interference; is a pulse interference signal, Represents the time shift of the time series, which is a non-negative integer; is the impulse signal amplitude, is a unit impulse signal; To perform discrete Fourier transform on the actual pulse interference signal; To perform discrete Fourier transform on noise level signal containing impulse interference; is the number of discrete Fourier transform points; That is, by subtracting the pulse interference signal from the frequency domain noise signal containing pulse interference, a frequency domain noise signal without pulse interference is obtained, thereby eliminating the influence on the frequency domain characteristics of the radar echo.

[0031] In this embodiment, the pulse-free radar echo signal processing steps include: obtaining a pulse-free radar echo signal and preprocessing it to obtain a power spectrum density sequence of the echo signal in each distance unit; arranging the power spectrum density sequence in ascending order based on the power value intensity; integrating the power spectrum sequence after ascending order from low to high; determining a total power interval for the power spectrum sequence after integration; and determining the total power interval based on the maximum total power value within the total power interval. And the corresponding spectrum points calculate the mean power to obtain the noise level corresponding to the radar echo signal without pulse interference , and set the signal / noise level threshold and the impulse interference noise level threshold.

[0032] The radar echo signal to be processed is processed as follows: outside the second total power interval, the difference between the total power of each spectrum point and the maximum total power value in the second total power interval is calculated; when the power difference exceeds the set signal / clutter level threshold, the spectrum point is determined to be a signal or a clutter level signal; within the second total power interval, the characteristic that the pulse interference signal can be approximated to the impulse signal is used, that is, the power of each spectrum point in the power spectrum sequence corresponding to the radar echo signal with pulse interference should be: the superposition of the echo signal power without pulse interference and the pulse interference signal power at each spectrum point in the power spectrum sequence corresponding to the radar echo without pulse interference, that is, within the second total power interval of the radar echo signal to be processed, the power value of the spectrum point should be , the radar echo signal power will increase the incremental level corresponding to the pulse interference signal When the increment level When the pulse interference level threshold is exceeded, the radar echo signal to be processed is determined to be a radar echo signal with pulse interference. At this time, the interference level corresponding to the incremental level is eliminated, that is, the influence of pulse interference on the frequency domain characteristics of the radar echo is eliminated. For example, Figure 3 shown.

[0033] In some embodiments, performing integration processing on the power spectrum after being sorted in ascending order from low to high includes: Arrange in ascending order The power value of each spectrum point, Sort in ascending order The sum of the power values of the spectrum points.

[0034] In some embodiments, determining the total power interval for the power spectrum sequence after integration includes: After integrating the power spectrum sequence from low to high, set the upper and lower power limits. When the power value of a spectrum point in the power spectrum sequence after integration is between the lower and upper power limits, determine the corresponding total power interval, and the corresponding spectrum point number is , is the spectrum point number corresponding to the upper limit power value, is the spectrum point number corresponding to the lower limit power value.

[0035] In some embodiments, when there is no pulse interference, the maximum total power value is determined within the first total power interval. include: is the total power value of the spectrum point with the maximum power in the total power interval, is the serial number corresponding to the spectrum point.

[0036] In some embodiments, based on the maximum aggregate power value and the corresponding spectrum points to calculate the noise level include: .

[0037] In some embodiments, obtaining the impulse interference noise level threshold comprises: is the impulse interference noise level threshold.

[0038] In some embodiments, further comprising: Outside the second total power interval, calculate the total power of each spectrum point and the maximum total power value in the total power interval The difference of is used to obtain the difference set; Obtaining a minimum value among the differences corresponding to the difference value set that exceeds the signal / clutter level threshold, and obtaining a corresponding spectrum point as a first spectrum point; The power value of the first spectrum point is used as the upper limit power value.

[0039] In some embodiments, further comprising: When the increment level Exceeds the impulse noise level threshold When the corresponding spectrum point is determined to be a noise level signal, the incremental level Pulse interference signal The corresponding interference level.

[0040] In some embodiments, performing pulse interference noise elimination processing on the noise level signal containing pulse interference includes: is the frequency domain noise signal without pulse interference, is a frequency domain noise signal containing pulse interference, is the frequency domain signal of pulse interference; is a pulse interference signal, Represents the time shift of the time series, which is a non-negative integer; is the impulse signal amplitude, is a unit impulse signal; To perform discrete Fourier transform on the actual pulse interference signal.

[0041] In some embodiments, further comprising: To perform discrete Fourier transform on noise level signal containing impulse interference; is the number of discrete Fourier transform points.

[0042] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computing software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0043] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0044] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo, characterized in that: include: Obtain the radar echo signal without pulse interference and preprocess it to obtain the power spectrum sequence of each range unit; Arranging the power spectrum sequence in ascending order based on power value intensity; The power spectrum sequence after ascending order is integrated from low to high; For the power spectrum sequence after the integration process, a total power interval is determined, which is recorded as a first total power interval; In the first total power interval, based on the maximum total power value And the corresponding spectrum points calculate the mean power to obtain the noise level corresponding to the radar echo signal without pulse interference ; Set the signal / clutter level threshold and the impulse interference noise level threshold; Obtaining a total power interval of the radar echo signal to be processed, recorded as a second total power interval; calculating, outside the second total power interval, a difference between the total power of each spectrum point and the maximum total power value within the second total power interval, and determining, when the difference exceeds the signal / clutter level threshold, that the corresponding spectrum point is a signal or a clutter level signal; In the second total power interval, the noise level of each spectrum point in the corresponding power spectrum sequence is the noise level of the radar echo signal without pulse interference. Incremental level corresponding to pulse interference signal When the noise level estimated in the second total power interval and the noise level corresponding to the radar echo signal without pulse interference are superimposed, When the difference exceeds the pulse interference noise level threshold, the radar echo signal to be processed is determined to be an echo signal containing pulse interference, and the corresponding difference is the incremental level corresponding to the pulse interference signal. ; The noise level signal containing pulse interference is processed to eliminate the pulse interference noise.

2. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 1, characterized in that: The power spectrum after being sorted in ascending order is integrated from low to high, including: Arrange in ascending order The power value of each spectrum point, Sort in ascending order The sum of the power values of the spectrum points.

3. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 1, characterized in that: For the power spectrum sequence after integration, determining the total power interval includes: After integrating the power spectrum sequence from low to high, set the upper and lower power limits. When the power value of a spectrum point in the power spectrum sequence after integration is between the lower and upper power limits, determine the corresponding total power interval, and the corresponding spectrum point number is , is the spectrum point number corresponding to the upper limit power value, is the spectrum point number corresponding to the lower limit power value.

4. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 1, characterized in that: When there is no pulse interference, the maximum total power value is determined within the first total power interval. include: is the total power value of the spectrum point with the maximum power in the total power interval, is the serial number corresponding to the spectrum point.

5. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 4, characterized in that: Based on the maximum total power value and the corresponding spectrum points to calculate the noise level include: 。 6. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 1, characterized in that: The acquisition of the impulse interference noise level threshold comprises: is the impulse interference noise level threshold.

7. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 3, characterized in that: Also includes: Outside the second total power interval, calculate the total power of each spectrum point and the maximum total power value in the total power interval The difference of is used to obtain the difference set; Obtaining a minimum value among the differences corresponding to the difference value set that exceeds the signal / clutter level threshold, and obtaining a corresponding spectrum point as a first spectrum point; The power value of the first spectrum point is used as the upper limit power value.

8. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echoes according to claim 6, characterized in that: Also includes: The noise level estimated in the second total power interval and the noise level corresponding to the radar echo signal without pulse interference The difference exceeds the impulse noise level threshold When the radar echo signal to be processed is determined to be an echo signal containing pulse interference, the incremental level Pulse interference signal The corresponding noise level.

9. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echoes according to claim 8, characterized in that: The process of eliminating the pulse interference noise from the noise level signal containing the pulse interference includes: is a frequency domain noise signal without pulse interference, is a frequency domain noise signal containing pulse interference, is the frequency domain signal of pulse interference; is a pulse interference signal, Represents the time shift of the time series, which is a non-negative integer; is the impulse signal amplitude, is a unit impulse signal; To perform discrete Fourier transform on the actual pulse interference signal.

10. The method for eliminating the influence of pulse interference on the frequency domain characteristics of radar echo according to claim 9, characterized in that: Also includes: To perform discrete Fourier transform on noise level signal containing impulse interference; is the number of discrete Fourier transform points.

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