Continuous wave radar hovering small unmanned aerial vehicle detection method and device, storage medium

Abstract

The application discloses a continuous wave radar hovering small unmanned aerial vehicle detection method and device, and a storage medium, and comprises the following steps: setting two groups of channels to collect echo signals of the continuous wave radar, one group being a reference channel and the other group being a receiving channel, wherein the collected data of the reference channel is an echo signal when there is no target, and the collected data of the receiving channel is an echo signal when it is needed to detect whether a target exists; and an improved Kalman filter is used to suppress ground clutter in the collected echo signal. The continuous wave radar hovering small unmanned aerial vehicle detection method and device, and the storage medium, obtain a clutter time-frequency signal and a target time-frequency signal of a detection area through short-time Fourier transform, so as to construct a three-dimensional time-frequency matrix, estimate a rotor micro-Doppler frequency of the unmanned aerial vehicle, can solve the echo spectrum range gate aliasing problem, meanwhile, the influence of noise is reduced, a method for distinguishing whether a hovering unmanned aerial vehicle exists is given, and effective detection of the hovering unmanned aerial vehicle is realized.

Description

Technical Field

[0001] This invention relates to a method, device, and storage medium for detecting hovering small unmanned aerial vehicles using continuous wave radar, belonging to the field of continuous wave radar target detection technology. Background Technology

[0002] With the increasing popularity of commercial drones, drones are being used more and more widely in military and civilian fields, which also brings potential security threats.

[0003] Due to their small radar cross-section (RCS) and low flight altitude, small unmanned aerial vehicles (UAVs) are easily obscured by ground clutter, especially hovering UAVs, where the Doppler characteristics are not obvious. This poses a challenge to radar detection of UAVs and has become a technical problem that urgently needs to be solved. Through feature modeling and analysis of low-speed small UAVs, it is found that the rotors of UAVs exhibit micro-Doppler characteristics when hovering.

[0004] To address the issue of weak effective detection feature energy in echoes, conventional filtering and noise cancellation methods exist. However, when these methods are applied to hovering UAV detection, aliasing still occurs in the range gate echo spectrum of the micro-Doppler feature echoes.

[0005] Therefore, in order to avoid the influence of clutter and target mixing on the detection results, there is an urgent need for a continuous wave radar hovering small UAV detection method, device, and storage medium. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a continuous wave radar method, device, and storage medium for detecting hovering small unmanned aerial vehicles (UAVs). By obtaining the clutter time-frequency signal and target time-frequency signal of the detection area through short-time Fourier transform, a three-dimensional time-frequency matrix is ​​constructed to estimate the micro-Doppler frequency of the UAV rotor. This can solve the problem of range gate aliasing in the echo spectrum, while reducing the influence of noise. A method for determining the presence of hovering UAVs is also provided, achieving effective detection of hovering UAVs.

[0007] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0008] In a first aspect, the present invention provides a method for detecting small unmanned aerial vehicles (UAVs) using continuous wave radar hovering, the method comprising the following steps:

[0009] Two sets of channels are set up to collect echo signals from the continuous wave radar: one is a reference channel, and the other is a receiving channel. The data collected by the reference channel is the echo signal when there is no target, and the data collected by the receiving channel is the echo signal when it is necessary to detect whether there is a target.

[0010] An improved Kalmas filter is used to suppress ground clutter in the acquired echo signal;

[0011] Based on the data acquired from the reference channel and the receiving channel, the clutter time-frequency signal and the target time-frequency signal in the detection area are obtained by short-time Fourier transform, respectively.

[0012] Based on the obtained clutter time-frequency signal and target time-frequency signal, mean cancellation filtering of the residual echo is performed to obtain clutter time-domain signal and target echo time-domain signal;

[0013] Based on the obtained clutter time-domain signal and target echo time-domain signal, adaptive constant false alarm rate (CFAR) detection is performed to obtain the target time-domain characteristic map.

[0014] Based on the obtained target time-domain characteristic map, the peak method is used to estimate parameters and obtain the Doppler unit with the largest signal amplitude at each sampling time.

[0015] The signal energy of the obtained Doppler cells is summed. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that a hovering UAV exists.

[0016] Furthermore, the residual echo mean cancellation filtering includes the following steps:

[0017] The clutter time-frequency signal is filtered in the frequency domain by a Kalmas filter, and then the clutter time-domain signal is obtained by inverse short-time Fourier transform.

[0018] The target time-frequency signal is filtered by a Kalmas filter, then subjected to an inverse short-time Fourier transform, and finally subtracted from the clutter time-domain signal to obtain the echo time-domain signal.

[0019] Furthermore, the adaptive constant false alarm rate (CFAR) detection includes the following steps:

[0020] The clutter time-frequency characteristics near each unit The average amplitude of the signals from each detection unit is set as a threshold.

[0021] Compare the signal amplitude of each cell in the target time-frequency characteristics with the threshold value obtained in that cell;

[0022] If the signal amplitude is greater than the threshold, the signal amplitude of the unit remains unchanged; if the signal amplitude is less than the threshold, the signal amplitude of the unit is set to 0.

[0023] After processing, the target time-domain characteristic map is obtained again.

[0024] Furthermore, the improved method for the Kalmas filter includes the following steps:

[0025] design MTI cascaded FFT filter bank;

[0026] Number zero and number The amplitude-frequency response of filter A is subtracted and the absolute value is taken, then a cutoff frequency of A is cascaded. The low-pass filter is used to obtain the improved Kalmas filter with the following amplitude-frequency response:

[0027] (1);

[0028] In the formula, This is the pulse repetition period.

[0029] Furthermore, the aforementioned The weights of the group filter are

[0030] (2);

[0031] In the formula, Indicates the first One tap. Indicates the first One filter.

[0032] Furthermore, the first The frequency response function of each filter is:

[0033] (3);

[0034] In the formula, This is the pulse repetition period.

[0035] Furthermore, the amplitude-frequency response of the filter is

[0036] (4);

[0037] In the formula, This is the pulse repetition period.

[0038] Secondly, the present invention provides a continuous wave radar hovering small unmanned aerial vehicle (UAV) detection device, the device comprising:

[0039] Echo signal acquisition module: used to set up two sets of channels to acquire echo signals from continuous wave radar, one set as a reference channel and the other set as a receiving channel. The data acquired by the reference channel is the echo signal when there is no target, and the data acquired by the receiving channel is the echo signal when it is necessary to detect whether there is a target.

[0040] Ground clutter suppression module: Used to suppress ground clutter in the acquired echo signal using an improved Kalmas filter;

[0041] Time-frequency characteristic acquisition module: used to obtain the clutter time-frequency signal and target time-frequency signal of the detection area based on the data collected by the reference channel and the receiving channel through short-time Fourier transform, respectively;

[0042] Residual echo mean cancellation filtering module: used to perform residual echo mean cancellation filtering based on the obtained clutter time-frequency signal and target time-frequency signal to obtain clutter time-domain signal and target echo time-domain signal;

[0043] Target time-domain characteristic map acquisition module: used to perform adaptive constant false alarm rate detection based on the obtained clutter time-domain signal and target echo time-domain signal, and obtain the target time-domain characteristic map;

[0044] Doppler frequency estimation module: used to perform parameter estimation using the peak method based on the obtained target time-domain characteristic map, and obtain the Doppler unit with the largest signal amplitude at each sampling time;

[0045] Drone detection module: It is used to sum the signal energy of the obtained Doppler cells. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that there is a hovering drone.

[0046] Thirdly, a continuous wave radar hovering small unmanned aerial vehicle detection device is characterized by including a processor and a storage medium;

[0047] The storage medium is used to store instructions;

[0048] The processor is configured to operate according to the instructions to perform the steps of the method according to the first aspect.

[0049] Fourthly, a computer-readable storage medium having a computer program stored thereon, characterized in that, when executed by a processor, the program implements the steps of the method described in the first aspect.

[0050] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0051] The continuous wave radar hovering small UAV detection method, device, and storage medium provided by this invention obtain clutter time-frequency signals and target time-frequency signals in the detection area through short-time Fourier transform to construct a three-dimensional time-frequency matrix and estimate the micro-Doppler frequency of the UAV rotor. This can solve the echo spectrum range gate aliasing problem, reduce the influence of noise, and provide a method to determine the existence of hovering UAVs, thus achieving effective detection of hovering UAVs. Attached Figure Description

[0052] Figure 1 This is a flowchart illustrating a continuous wave radar hovering method for detecting small unmanned aerial vehicles provided in Embodiment 1;

[0053] Figure 2 This is a signal processing flowchart of a continuous wave radar hovering small UAV detection method;

[0054] Figure 3 It is a three-dimensional time-frequency matrix obtained by short-time Fourier transform. Detailed Implementation

[0055] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other.

[0056] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship. Example 1

[0057] Figure 1 This is a flowchart of a continuous wave radar hovering small unmanned aerial vehicle (UAV) detection method according to Embodiment 1 of the present invention. The continuous wave radar hovering small UAV detection method provided in this embodiment can be applied to a terminal and can be executed by a continuous wave radar hovering small UAV detection device. This device can be implemented by software and / or hardware and can be integrated into the terminal, such as any smartphone, tablet, or computer device with communication capabilities. See also... Figure 1 The method implemented in this way specifically includes the following steps:

[0058] Two sets of channels are set up to collect echo signals from the continuous wave radar: one is a reference channel, and the other is a receiving channel. The data collected by the reference channel is the echo signal when there is no target, and the data collected by the receiving channel is the echo signal when it is necessary to detect whether there is a target.

[0059] Reference Channel Background clutter sampled at different times is

[0060]

[0061] Receive channel The target echoes obtained by sampling at different times are

[0062]

[0063] in, This represents a fast-time variable.

[0064] An improved Kalmas filter is used to suppress ground clutter in the acquired echo signal. The frequency response of this filter rises rapidly at the zero Doppler frequency to ensure the detection capability of micro-Doppler targets. At the same time, it has a similar frequency response to the low-pass filter at the high Doppler frequency, which can suppress high-frequency clutter. In addition, by windowing the signal (Hamming window, etc.), the filter can be made to have a gain for micro-Doppler signals.

[0065] Based on the data acquired from the reference channel and the receiving channel, the clutter time-frequency signal and the target time-frequency signal of the detection area are obtained through short-time Fourier transform, respectively. The obtained clutter time-frequency signal and target time-frequency signal of the detection area are three-dimensional data matrices of time, Doppler frequency shift, and signal amplitude, such as... Figure 2 As shown in the figure, with time as the X-axis and Doppler frequency shift as the Y-axis, a Doppler cell at a certain sampling time can be uniquely determined. Indicates the fast time dimension, Indicates the Doppler dimension. Indicates signal amplitude;

[0066] The results are as follows:

[0067] (3)

[0068] (4)

[0069] In the formula, To move the signal along the time axis, a set of local spectrum time window functions of the signal are obtained by segmenting the signal.

[0070] Based on the obtained clutter time-frequency signal and target time-frequency signal, residual echo mean cancellation filtering is performed to obtain clutter time-domain signal and target echo time-domain signal. The data acquired by the reference channel and the receiving channel are processed by the Kalmas filter and then time-domain cancellation is performed. After filtering out zero-frequency and high-frequency clutter, clutter at the micro-Doppler frequency is also suppressed, thus improving the signal-to-noise ratio.

[0071] Based on the obtained clutter time-domain signal and target echo time-domain signal, adaptive constant false alarm rate (CFAR) detection is performed to obtain the target time-domain characteristic map.

[0072] Based on the obtained target time-domain characteristic map, the peak method is used for parameter estimation to obtain the Doppler unit with the largest signal amplitude at each sampling time:

[0073] (5)

[0074] In the formula, The sampling time is defined as follows: Simultaneously, the set of Doppler units with the largest signal amplitude at each sampling time is recorded, and is defined as... .

[0075] The signal energy of the obtained Doppler cells is summed. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that a hovering UAV exists.

[0076] The discrimination method is expressed as follows:

[0077] (6)

[0078] (7)

[0079] In the formula, Summing the signal energy of the Doppler cell corresponding to the time-frequency characteristics of clutter. To The magnification factor can be adjusted freely according to the environment and requirements; in this embodiment, the background environment consists of trees and buildings. Set to four times.

[0080] In some embodiments, the residual echo mean cancellation filtering includes the following steps:

[0081] The clutter time-frequency signal is filtered in the frequency domain using a Kalmar filter to obtain... And then Inverse short-time Fourier transform is used to obtain the clutter time-domain signal;

[0082] The target time-frequency signal is filtered through a Kalmar filter to obtain... And then The inverse short-time Fourier transform is then subtracted from the clutter time-domain signal to obtain the target echo time-domain signal.

[0083] The specific process is as follows:

[0084] (8)

[0085] (9)

[0086] Then and Take the inverse short-time Fourier transform to obtain the time-domain signal again. and Subtracting the two yields the target echo time-domain signal.

[0087] (10)

[0088] In some embodiments, the adaptive constant false alarm rate (CFAR) detection includes the following steps:

[0089] The clutter time-frequency characteristics near each unit The average amplitude of the signals from each detection unit is set as a threshold. During this process, the detection threshold for each Doppler unit signal is determined by analyzing the clutter time-frequency characteristics near each corresponding Doppler unit. The average signal amplitude of each detection unit is used;

[0090] (11)

[0091] Compare the signal amplitude of each cell in the target time-frequency characteristics with the threshold value obtained in that cell;

[0092] If the signal amplitude is greater than the threshold, the signal amplitude of the unit remains unchanged; if the signal amplitude is less than the threshold, the signal amplitude of the unit is set to 0.

[0093] After processing, the target time-domain characteristic map is obtained again;

[0094] (12)

[0095] (13).

[0096] In some embodiments, the method for improving the Kalmas filter includes the following steps:

[0097] design MTI cascaded FFT filter bank;

[0098] Number zero and number The amplitude-frequency response of filter A is subtracted and the absolute value is taken, then a cutoff frequency of A is cascaded. The low-pass filter is used to obtain the improved Kalmas filter with the following amplitude-frequency response:

[0099] (14)

[0100] In the formula, This is the pulse repetition period.

[0101] In some embodiments, the The weights of the group filter are

[0102] (15)

[0103] In the formula, Indicates the first One tap. Indicates the first One filter.

[0104] In some embodiments, since each The value determines an independent filter response, corresponding to a different Doppler filter response; therefore, the first... The frequency response function of each filter is:

[0105] (16)

[0106] In the formula, This is the pulse repetition period.

[0107] In some embodiments, the amplitude-frequency characteristic of the filter is

[0108] (17)

[0109] In the formula, This is the pulse repetition period.

[0110] In summary, the continuous wave radar hovering small UAV detection method provided in this embodiment can solve the echo spectrum range gate aliasing problem by constructing a three-dimensional time-frequency matrix and estimating the micro-Doppler frequency of the UAV rotor, while reducing the influence of noise. It also provides a method for determining the presence of hovering UAVs and achieves effective detection of hovering UAVs. Example 2

[0111] This embodiment provides a continuous wave radar hovering small unmanned aerial vehicle (UAV) detection device, the device comprising:

[0112] Echo signal acquisition module: used to set up two sets of channels to acquire echo signals from continuous wave radar, one set as a reference channel and the other set as a receiving channel. The data acquired by the reference channel is the echo signal when there is no target, and the data acquired by the receiving channel is the echo signal when it is necessary to detect whether there is a target.

[0113] Ground clutter suppression module: Used to suppress ground clutter in the acquired echo signal using an improved Kalmas filter;

[0114] Time-frequency characteristic acquisition module: used to obtain the clutter time-frequency signal and target time-frequency signal of the detection area based on the data collected by the reference channel and the receiving channel through short-time Fourier transform, respectively;

[0115] Residual echo mean cancellation filtering module: used to perform residual echo mean cancellation filtering based on the obtained clutter time-frequency signal and target time-frequency signal to obtain clutter time-domain signal and target echo time-domain signal;

[0116] Target time-domain characteristic map acquisition module: used to perform adaptive constant false alarm rate detection based on the obtained clutter time-domain signal and target echo time-domain signal, and obtain the target time-domain characteristic map;

[0117] Doppler frequency estimation module: used to perform parameter estimation using the peak method based on the obtained target time-domain characteristic map, and obtain the Doppler unit with the largest signal amplitude at each sampling time;

[0118] Drone detection module: It is used to sum the signal energy of the obtained Doppler cells. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that there is a hovering drone.

[0119] The continuous wave radar hovering small UAV detection device provided in this embodiment of the invention can execute the continuous wave radar hovering small UAV detection method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method. Example 3

[0120] This invention also provides a continuous wave radar hovering small unmanned aerial vehicle detection device, including a processor and a storage medium;

[0121] The storage medium is used to store instructions;

[0122] The processor is configured to operate according to the instructions to perform the steps of the following method:

[0123] Two sets of channels are set up to collect echo signals from the continuous wave radar: one is a reference channel, and the other is a receiving channel. The data collected by the reference channel is the echo signal when there is no target, and the data collected by the receiving channel is the echo signal when it is necessary to detect whether there is a target.

[0124] An improved Kalmas filter is used to suppress ground clutter in the acquired echo signal;

[0125] Based on the data acquired from the reference channel and the receiving channel, the clutter time-frequency signal and the target time-frequency signal in the detection area are obtained by short-time Fourier transform, respectively.

[0126] Based on the obtained clutter time-frequency signal and target time-frequency signal, mean cancellation filtering of the residual echo is performed to obtain clutter time-domain signal and target echo time-domain signal;

[0127] Based on the obtained clutter time-domain signal and target echo time-domain signal, adaptive constant false alarm rate (CFAR) detection is performed to obtain the target time-domain characteristic map.

[0128] Based on the obtained target time-domain characteristic map, the peak method is used to estimate parameters and obtain the Doppler unit with the largest signal amplitude at each sampling time.

[0129] The signal energy of the obtained Doppler cells is summed. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that a hovering UAV exists. Example 4

[0130] This invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the following method:

[0131] Two sets of channels are set up to collect echo signals from the continuous wave radar: one is a reference channel, and the other is a receiving channel. The data collected by the reference channel is the echo signal when there is no target, and the data collected by the receiving channel is the echo signal when it is necessary to detect whether there is a target.

[0132] An improved Kalmas filter is used to suppress ground clutter in the acquired echo signal;

[0133] Based on the data acquired from the reference channel and the receiving channel, the clutter time-frequency signal and the target time-frequency signal in the detection area are obtained by short-time Fourier transform, respectively.

[0134] Based on the obtained clutter time-frequency signal and target time-frequency signal, mean cancellation filtering of the residual echo is performed to obtain clutter time-domain signal and target echo time-domain signal;

[0135] Based on the obtained clutter time-domain signal and target echo time-domain signal, adaptive constant false alarm rate (CFAR) detection is performed to obtain the target time-domain characteristic map.

[0136] Based on the obtained target time-domain characteristic map, the peak method is used to estimate parameters and obtain the Doppler unit with the largest signal amplitude at each sampling time.

[0137] The signal energy of the obtained Doppler cells is summed. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that a hovering UAV exists.

[0138] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0139] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0140] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0141] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0142] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting small unmanned aerial vehicles using continuous wave radar hovering, characterized in that, The method includes the following steps: Two sets of channels are set up to collect echo signals from the continuous wave radar: one is a reference channel, and the other is a receiving channel. The data collected by the reference channel is the echo signal when there is no target, and the data collected by the receiving channel is the echo signal when it is necessary to detect whether there is a target. An improved Kalmas filter is used to suppress ground clutter in the acquired echo signal; Based on the data acquired from the reference channel and the receiving channel, the clutter time-frequency signal and the target time-frequency signal in the detection area are obtained by short-time Fourier transform, respectively. Based on the obtained clutter time-frequency signal and target time-frequency signal, mean cancellation filtering of the residual echo is performed to obtain clutter time-domain signal and target echo time-domain signal; Based on the obtained clutter time-domain signal and target echo time-domain signal, adaptive constant false alarm rate (CFAR) detection is performed to obtain the target time-domain characteristic map. Based on the obtained target time-domain characteristic map, the peak method is used to estimate parameters and obtain the Doppler unit with the largest signal amplitude at each sampling time. The signal energy of the obtained Doppler cells is summed. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that a hovering UAV exists. The residual echo mean cancellation filtering includes the following steps: The clutter time-frequency signal is filtered in the frequency domain by a Kalmas filter, and then the clutter time-domain signal is obtained by inverse short-time Fourier transform. The target time-frequency signal is filtered by a Kalmas filter, then subjected to an inverse short-time Fourier transform, and finally subtracted from the clutter time-domain signal to obtain the echo time-domain signal.

2. The continuous wave radar hovering small UAV detection method according to claim 1, characterized in that, The adaptive constant false alarm rate (CFAR) detection includes the following steps: Set the average signal amplitude of each detection unit near each unit of the clutter time-frequency characteristic as the threshold; Compare the signal amplitude of each cell in the target time-frequency characteristics with the threshold value obtained in that cell; If the signal amplitude is greater than the threshold, the signal amplitude of the unit remains unchanged; if the signal amplitude is less than the threshold, the signal amplitude of the unit is set to 0. After processing, the target time-domain characteristic map is obtained again.

3. The continuous wave radar hovering small UAV detection method according to claim 1, characterized in that, The improved method for the Kalmas filter includes the following steps: design MTI cascaded FFT filter bank; Number zero and number The amplitude-frequency response of filter A is subtracted and the absolute value is taken, then a cutoff frequency of A is cascaded. The low-pass filter is used to obtain the improved Kalmas filter with the following amplitude-frequency response: （1）； In the formula, This is the pulse repetition period.

4. The continuous wave radar hovering small UAV detection method according to claim 3, characterized in that, The The weights of the group filter are （2）； In the formula, Indicates the first One tap. Indicates the first One filter.

5. The continuous wave radar hovering small UAV detection method according to claim 4, characterized in that, No. The frequency response function of each filter is: （3）； In the formula, This is the pulse repetition period.

6. The continuous wave radar hovering small UAV detection method according to claim 5, characterized in that, The amplitude-frequency response of the filter is （4）； In the formula, This is the pulse repetition period.

7. A continuous wave radar hovering small unmanned aerial vehicle (UAV) detection device, characterized in that, The device includes: Echo signal acquisition module: used to set up two sets of channels to acquire echo signals from continuous wave radar, one set as a reference channel and the other set as a receiving channel. The data acquired by the reference channel is the echo signal when there is no target, and the data acquired by the receiving channel is the echo signal when it is necessary to detect whether there is a target. Ground clutter suppression module: Used to suppress ground clutter in the acquired echo signal using an improved Kalmas filter; Time-frequency characteristic acquisition module: used to obtain the clutter time-frequency signal and target time-frequency signal of the detection area based on the data collected by the reference channel and the receiving channel through short-time Fourier transform, respectively; Residual echo mean cancellation filtering module: used to perform residual echo mean cancellation filtering based on the obtained clutter time-frequency signal and target time-frequency signal to obtain clutter time-domain signal and target echo time-domain signal; Target time-domain characteristic map acquisition module: used to perform adaptive constant false alarm rate detection based on the obtained clutter time-domain signal and target echo time-domain signal, and obtain the target time-domain characteristic map; Doppler frequency estimation module: used to perform parameter estimation using the peak method based on the obtained target time-domain characteristic map, and obtain the Doppler unit with the largest signal amplitude at each sampling time; Drone detection module: It is used to sum the signal energy of the obtained Doppler cells. When the summation result is greater than a certain multiple of the summation of the signal energy of the Doppler cells corresponding to the clutter time-frequency characteristics, it is considered that there is a hovering drone. The residual echo mean cancellation filtering includes the following steps: The clutter time-frequency signal is filtered in the frequency domain by a Kalmas filter, and then the clutter time-domain signal is obtained by inverse short-time Fourier transform. The target time-frequency signal is filtered by a Kalmas filter, then subjected to an inverse short-time Fourier transform, and finally subtracted from the clutter time-domain signal to obtain the echo time-domain signal.

8. A continuous wave radar hovering small unmanned aerial vehicle (UAV) detection device, characterized in that, Including processor and storage media; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method according to any one of claims 1 to 6.

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