High-voltage line detection and ranging method, system and device based on millimeter-wave radar

Abstract

The present invention relates to the field of radar target detection technology, and in particular to a method, system, and device for detecting and ranging high-voltage lines based on millimeter-wave radar. The method comprises the following steps: transmitting a linear frequency-modulated pulse signal to a high-voltage line area; obtaining an original echo signal reflected from the target high-voltage line based on the linear frequency-modulated pulse signal, preprocessing the original echo signal to obtain a preprocessed echo signal; performing pulse compression processing on the linear frequency-modulated pulse signal and the preprocessed echo signal in the frequency domain to obtain a frequency-domain pulse compression signal; and obtaining the target distance based on the frequency-domain pulse compression signal. The present invention utilizes millimeter-wave radar technology to transmit a linear frequency-modulated pulse signal and receive an echo reflected from the high-voltage line. Through preprocessing, frequency-domain pulse compression, moving target detection, and non-coherent accumulation, the method achieves accurate detection and ranging of high-voltage lines.

Description

Technical Field

[0001] The present invention relates to the field of radar target detection technology, and in particular to a high-voltage line detection and ranging method, system and device based on millimeter-wave radar. Background Art

[0002] When performing specialized operations in the power industry, especially live transmission line work, workers, constrained by site conditions, often rely on visual judgment to determine safe working distances. However, this approach can introduce errors due to subjective judgment and interference from external environmental factors, and can also increase the risk of live line work. Therefore, developing a transmission line-based spatial limit warning system to prevent large-scale machinery from contacting the line is crucial for improving operational safety.

[0003] Currently, the alarm detection technologies adopted by the industry primarily include power-frequency electric field measurement, ultrasonic ranging, and optical image detection. However, each of these technologies faces certain challenges in practical application. Specifically, due to the densely packed wiring around high-voltage towers and the complex and ever-changing electromagnetic environment, existing power-frequency electric field sensing technology is susceptible to electromagnetic interference in this environment, resulting in large fluctuations in measurement data and insufficient stability. Furthermore, the typically small diameter of high-voltage transmission lines causes severe attenuation of ultrasonic signals during propagation, resulting in weak received signal strength. This, coupled with potential blurring and distortion during image acquisition, impacts the accuracy of ultrasonic ranging and optical image detection methods. Furthermore, both methods are highly susceptible to weather conditions. For example, inclement weather such as rain and snow can significantly affect ultrasonic propagation and image clarity, making it difficult to meet the system's requirements for high precision and reliability. Summary of the Invention

[0004] To this end, the technical difficulty that the present invention aims to solve is that the traditional visual inspection method is largely limited by the subjective errors of human judgment and the interference of complex and changeable environmental factors, especially in an environment with low signal-to-noise ratio. This influence is particularly prominent, thereby greatly reducing the accuracy of high-voltage line detection distance estimation.

[0005] To solve the above technical problems, the present invention uses millimeter-wave radar signal correlation processing technology, clutter cancellation technology, and signal clustering technology to complete the detection and ranging of high-voltage power lines, and provides a high-voltage line detection and ranging method, system and device based on millimeter-wave radar, which solves the problem of detecting and ranging weak echo signals of power lines under low signal-to-noise ratio, and provides technical support for the subsequent transmission line space limiting system to prevent large-scale machinery construction from hitting the line.

[0006] The specific steps of the high-voltage line detection and ranging method based on millimeter wave radar are as follows:

[0007] S1: Transmits linear frequency modulation pulse signal to the high-voltage line area;

[0008] S2: acquiring an original echo signal reflected by the target high-voltage line based on the linear frequency modulation pulse signal, and preprocessing the original echo signal to obtain a preprocessed echo signal;

[0009] S3: performing pulse compression processing on the linear frequency modulation pulse signal and the preprocessed echo signal in the frequency domain to obtain a frequency domain pulse compression signal;

[0010] S4: Obtaining a target distance based on the frequency domain pulse pressure signal.

[0011] In one embodiment of the present invention, the linear frequency modulation pulse signal r(t',n) is:

[0012]

[0013] Where t′=t-nT represents the intra-pulse time, i.e., the fast time, in seconds, rect represents the rectangular function operation, t is the acquisition time, n=0, ..., N-1, N is the number of accumulated pulses, Tp is the pulse width, T is the pulse repetition period, k is the modulation frequency of the transmitting signal, and fc is the carrier frequency.

[0014] In one embodiment of the present invention, the original echo signal s(t',n) is expressed as:

[0015] s(t',n)=A r r[t'-τ(t),n]+w(t',n)

[0016] in, v is the lifting speed of the vehicle arm, A r represents the echo amplitude in volts, w(t′,n) represents Gaussian white noise with a mean of 0, R(t) represents the distance between the radar and the target high-voltage line at time t, in meters, R0 represents the distance between the radar and the target high-voltage line at the initial time t0, and c represents the electromagnetic wave propagation speed, which is 3×10 8 Meters / second.

[0017] In one embodiment of the present invention, in S2, the step of obtaining the preprocessed echo signal is as follows:

[0018] S21: performing pulse cancellation processing on the original echo signal to obtain an echo signal after pulse cancellation processing;

[0019] S22: performing interference suppression on the echo signal after the pulse cancellation processing to obtain an interference-suppressed echo signal, that is, the pre-processed echo signal.

[0020] In one embodiment of the present invention, the echo signal s after the pulse cancellation processing MTI (t',n) is:

[0021] s MTI (t',n)=s(t',n)-2s(t'-T,n)+s(t'-2T,n).

[0022] In one embodiment of the present invention, the preprocessed echo signal S(f',n) is:

[0023] S(f',n)=FFT[s MTI (t',n)]

[0024] Among them, f'∈[-f d ,f d ], v is the lifting speed of the vehicle arm, in m / s, θ is the radar line of sight angle; FFT[·] represents the fast Fourier transform function.

[0025] In one embodiment of the present invention, the frequency domain pulse pressure signal s pc (t',n) is:

[0026] s pc (t',n)=IFFT[FFT[r(t',n)]S * (f',n)]

[0027] Among them, S * (f′, n) represents the conjugate of the preprocessed echo signal S(f′, n), and IFFT[·] represents an inverse fast Fourier transform function.

[0028] In one embodiment of the present invention, in S4, the step of obtaining the target distance is as follows:

[0029] S41: After performing moving target detection processing on the frequency domain pulse pressure signal, setting a first number of iterations and a second number of iterations;

[0030] S42: Determine whether the first number of iterations has been reached:

[0031] If not, return to step S2 to perform non-coherent accumulation to obtain the non-coherent accumulation value calculated in each iteration;

[0032] If yes, filter out the maximum value among the multiple non-coherent accumulation values ​​and obtain the target distance information corresponding to the maximum value;

[0033] S43: Determine whether the second number of iterations has been reached:

[0034] If not, return to step S2 to obtain the target distance information corresponding to the maximum value in each non-coherent accumulation iterative calculation process;

[0035] If so, cluster the target distance information corresponding to multiple maximum values ​​to obtain the target distance.

[0036] In one embodiment of the present invention, in S41, the non-coherent accumulation value s obtained by each iteration is obtained. Q (t',n) is:

[0037]

[0038] Among them, s Q (t',n) represents the non-coherent accumulation value, MTD[·] represents the moving target detection function, and Q is the first iteration number.

[0039] In one embodiment of the present invention, in S41, the target distance information R1 corresponding to the maximum value is obtained as follows:

[0040]

[0041] Among them, s Q (t',n) represents the non-coherent accumulation value, T s Indicates the collection time interval in seconds.

[0042] Based on the same inventive concept, the present invention also provides a high-voltage line detection and ranging system based on millimeter-wave radar, which includes the following modules:

[0043] A pulse signal transmitting module is used to transmit a linear frequency modulation pulse signal to the high-voltage line area;

[0044] An echo signal acquisition and preprocessing module is used to acquire an original echo signal reflected by the high-voltage line based on the linear frequency modulation pulse signal, and preprocess the original echo signal to obtain a preprocessed echo signal;

[0045] a signal-to-noise ratio enhancement module, configured to perform pulse compression processing on the linear frequency modulation pulse signal and the preprocessed echo signal in the frequency domain to obtain a frequency domain pulse compression signal;

[0046] The target distance calculation module is used to obtain the target distance based on the frequency domain pulse pressure signal.

[0047] The present invention also provides a power transmission line alarm device, comprising a memory, a processor, and a computer program stored in the memory and runnable on the processor. The device is characterized in that when the processor executes the program, the steps of the high-voltage line detection and ranging method based on millimeter-wave radar are implemented to obtain the target distance between the operator and the target high-voltage line, and obtain the working safety distance based on the target distance.

[0048] The above technical solution of the present invention has the following advantages over the prior art:

[0049] 1. High-precision ranging: This technology transmits linear frequency-modulated pulse signals and receives the reflected echoes, cleverly using pulse compression technology to process them in the frequency domain, thereby significantly improving the accuracy of ranging.

[0050] 2. Strong anti-interference capability: Millimeter-wave radar technology inherently has strong anti-interference capabilities, enabling stable operation in complex climate environments. Furthermore, pulse cancellation and interference suppression in the pre-processing step further reduce the impact of noise and interference, improving ranging reliability.

[0051] 3. Strong adaptability and real-time performance: This technical solution is not only suitable for static high-voltage line detection, but can also perform real-time dynamic monitoring and precise ranging of dynamic targets through technical means such as dynamic target detection processing and non-coherent accumulation. This is of great significance for timely discovery and early warning of potential safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings, wherein

[0053] Figure 1 This is a flow chart of a high-voltage line detection and ranging method based on millimeter-wave radar provided in Example 1 of the present invention;

[0054] Figure 2 This is a specific flow chart of a high-voltage line detection and ranging method based on millimeter-wave radar provided in Example 1 of the present invention;

[0055] Figure 3 is a flow chart of a method for obtaining a preprocessed echo signal provided in the first embodiment of the present invention;

[0056] Figure 4 The waveform diagram of the target's distance position when the non-coherent accumulation number Q is 2 and the number of result comparisons H is 1;

[0057] Figure 5The waveform diagram of the target's distance position when the non-coherent accumulation number Q is 3 and the number of result comparisons H is 1;

[0058] Figure 6 The waveform diagram of the target's distance position when the non-coherent accumulation number Q is 2 and the number of result comparisons H is 3;

[0059] Figure 7 This is a structural diagram of a high-voltage line detection and ranging system based on millimeter-wave radar provided in the second embodiment of the present invention;

[0060] Description of the accompanying drawings in the specification: 100, pulse signal transmission module; 200, echo signal acquisition and preprocessing module; 300, signal-to-noise ratio enhancement module; 400, target distance calculation module. DETAILED DESCRIPTION

[0061] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0062] Example 1

[0063] Reference Figure 1 and Figure 2 As shown, the present invention provides a method for high-voltage line detection and ranging based on millimeter-wave radar, the steps of which are as follows:

[0064] S1: Transmits linear frequency modulation pulse signal (also called LFM signal) to the high voltage line area;

[0065] S2: acquiring an original echo signal reflected by the target high-voltage line based on the linear frequency modulation pulse signal, and preprocessing the original echo signal to obtain a preprocessed echo signal;

[0066] S3: performing pulse compression processing on the linear frequency modulation pulse signal and the preprocessed echo signal in the frequency domain to obtain a frequency domain pulse compression signal;

[0067] S4: Obtaining a target distance based on the frequency-domain pulse pressure signal, including:

[0068] S41: After performing moving target detection (MTD) processing on the frequency domain pulse pressure signal to distinguish between stationary targets and moving targets, a first iteration number for non-coherent accumulation and a second iteration number for clustering processing of target distance information are set;

[0069] S42: Determine whether the first number of iterations has been reached:

[0070] If not, return to step S2 to perform non-coherent accumulation to improve the detection capability of weak targets and obtain the non-coherent accumulation value calculated in each iteration;

[0071] If yes, filter out the maximum value among the multiple non-coherent accumulated values, and obtain the target distance information corresponding to the maximum value, which is the optimal estimate of the current iteration round;

[0072] S43: Determine whether the second number of iterations has been reached:

[0073] If not, return to step S2 to obtain the target distance information corresponding to the maximum value in each non-coherent accumulation iterative calculation process;

[0074] If so, cluster the target distance information corresponding to multiple maximum values ​​to remove false targets and duplicate targets and obtain the target distance.

[0075] As can be seen from the above technical solution, the present invention achieves accurate detection and ranging of high-voltage power lines by transmitting linear frequency-modulated pulse signals, acquiring and preprocessing the original echo signals, performing pulse compression processing in the frequency domain, and clustering moving target detection and target distance information based on the frequency-domain pulse compression signals. This method offers advantages such as high resolution, strong signal-to-noise ratio, and strong anti-interference capabilities, making it suitable for high-voltage power line detection and ranging tasks in various complex environments.

[0076] Furthermore, in step S1, a linear frequency modulation pulse signal is transmitted to the high-voltage line area, wherein the linear frequency modulation pulse signal r(t',n) is:

[0077]

[0078] Where t′=t-nT represents the intra-pulse time, i.e., the fast time, in seconds, rect represents the rectangular function operation, t is the acquisition time, n=0, ..., N-1, N is the number of accumulated pulses, Tp is the pulse width, T is the pulse repetition period, k is the modulation frequency of the transmitting signal, and fc is the carrier frequency.

[0079] The original echo signal reflected from the high-voltage line contains information such as the position and speed of the target (high-voltage line), but usually contains noise and interference. The original echo signal s(t',n) is expressed as:

[0080] s(t',n)=A r r[t'-τ(t),n]+w(t',n)

[0081] in, v is the lifting speed of the vehicle arm, A rrepresents the echo amplitude in volts, w(t′,n) represents Gaussian white noise with a mean of 0, R(t) represents the distance between the radar and the target high-voltage line at time t, in meters, R0 represents the distance between the radar and the target high-voltage line at the initial time t0, and c represents the electromagnetic wave propagation speed, which is 3×10 8 Meters / second.

[0082] like Figure 3 As shown, in step S2, based on the linear frequency modulation pulse signal, the original echo signal reflected by the target high-voltage line is obtained, and the original echo signal is preprocessed to improve the signal quality and facilitate subsequent pulse compression and target detection. Specifically, the steps of obtaining the preprocessed echo signal are as follows:

[0083] S21: Perform pulse cancellation processing on the original echo signal to obtain an echo signal s after pulse cancellation processing MTI (t',n):

[0084] s MTI (t',n)=s(t',n)-2s(t'-T,n)+s(t'-2T,n);

[0085] S22: performing interference suppression on the echo signal after the pulse cancellation processing to obtain an interference-suppressed echo signal, that is, the pre-processed echo signal S(f',n):

[0086] S(f',n)=FFT[s MTI (t',n)]

[0087] Among them, f'∈[-f d ,f d ], v is the lifting speed of the vehicle arm, v∈[-1,1], in m / s, f d ∈[-200,200], the unit is Hz, θ is the radar line of sight angle, the unit is radian; FFT[·] represents the fast Fourier transform function.

[0088] In order to improve the resolution and signal-to-noise ratio of the radar system and thus extract target information more accurately, the linear frequency modulation pulse signal and the pre-processed echo signal obtained in the above steps are pulse compressed in the frequency domain to obtain the frequency domain pulse compression signal s pc (t',n) is:

[0089] s pc (t',n)=IFFT[FFT[r(t',n)]S * (f',n)]

[0090] Among them, S *(f′, n) represents the conjugate of the preprocessed echo signal S(f′, n), and IFFT[·] represents an inverse fast Fourier transform function.

[0091] like Figure 2 As shown in FIG, the specific steps for obtaining the target distance include:

[0092] S41: To distinguish between stationary targets and moving targets, after performing moving target detection (MTD) processing on the frequency domain pulse pressure signal, setting a first iteration number Q for non-coherent accumulation and a second iteration number H for clustering processing of target distance information;

[0093] The larger the value of Q, the stronger the interference suppression capability, but the longer the calculation time. In practical applications, a compromise should be made between processing time and estimation accuracy. In this embodiment, considering that the calculation time is less than 200ms, the value of Q is 3.

[0094] The larger the value of H, the higher the stability of the target distance information, but the target result will have a greater delay. In this embodiment, considering that the calculation time is less than 200ms, the value of H is 3;

[0095] S42: Determine whether the first number of iterations Q has been reached:

[0096] If not, return to step S2 and perform non-coherent accumulation to improve the detection capability of weak targets, and obtain the non-coherent accumulation value s obtained by each iteration. Q (t',n) is:

[0097]

[0098] Among them, s Q (t',n) represents the non-coherent accumulation value, MTD[·] represents the moving target detection function, and Q is the first iteration number;

[0099] If so, filter out the maximum value among multiple non-coherent accumulation values ​​and obtain the target distance information corresponding to the maximum value, which is the optimal estimate R1 of the current iteration round:

[0100]

[0101] Among them, s Q (t',n) represents the non-coherent accumulation value, T s Indicates the collection time interval in seconds;

[0102] S43: Determine whether the second iteration number H is reached:

[0103] If not, return to step S2 to obtain the target distance information R2, R3...R corresponding to the maximum value in each non-coherent accumulation iterative calculation process.h ;

[0104] If so, cluster the target distance information corresponding to multiple maximum values ​​to remove false targets and duplicate targets, and obtain the target distance R T :

[0105]

[0106] Among them, R h+1 is the target distance information corresponding to the maximum value obtained in the h+1th iteration, R h is the target distance information corresponding to the maximum value obtained in the hth iteration, |R h+1 -R h |≤ΔR, ΔR represents the difference in distance between two adjacent tests, which is generally set within 30 cm, h∈[1,H].

[0107] When H=3, the target distance R T It is expressed as the following situations:

[0108] When R2-R1≤ΔR,

[0109] When |R3-R2|≤ΔR,

[0110] When |R2-R1|≤ΔR and |R3-R2|≤ΔR,

[0111] To verify the effectiveness of the high-voltage line detection and distance measurement method described in the present invention, different values ​​of the actual target distance, the number of non-coherent accumulation times Q, and the number of result comparison times H were set, and the distance estimation results were obtained accordingly. The error between the target distance estimation value and the actual target distance was then compared. Specifically, Figures 4 to 6 The following diagram shows the experimental results for actual target distances set at 4 meters, 6.5 meters, and 7 meters. The straight line represents the amplitude of the noise floor, the curved line represents the actual amplitude of the measured signal, and the horizontal axis corresponding to the position of maximum amplitude represents the measured target distance.

[0112] Depend on Figure 4 It can be seen that the target distance estimation value is highly consistent with the actual value, which fully verifies the accuracy of the method of the present invention in estimating the high-voltage line distance. Figure 4 The processing result, Figure 5 Although the target amplitude is reduced, the signal-to-noise ratio remains high. Comparing the target distance estimate with the actual target distance shows that the estimated value is still very accurate, further confirming the effectiveness of the proposed method for detecting and estimating high-voltage power lines in low signal-to-noise ratio environments.

[0113] Figure 6 The distance estimation results are shown when the target distance is 7 meters. Figure 4 and Figure 5 In contrast, the echo intensity is further weakened at this point, and the signal-to-noise ratio (SNR) for target detection also decreases. However, by comparing the estimated target distance with the actual target distance, we can still conclude that the estimated value is accurate. This result further verifies the effectiveness of the proposed method for detecting and estimating high-voltage power lines under low SNR conditions.

[0114] In summary, the high-voltage line detection and ranging method proposed in the present invention has demonstrated good performance and accuracy under different conditions, providing strong technical support for high-voltage line safety monitoring.

[0115] Example 2

[0116] Based on the same inventive concept, the present invention also provides a high-voltage line detection and ranging system based on millimeter-wave radar, such as Figure 7 As shown, the system includes the following modules:

[0117] The pulse signal transmitting module 100 is used to transmit a linear frequency modulation pulse signal to the high-voltage line area;

[0118] The echo signal acquisition and preprocessing module 200 is used to acquire the original echo signal reflected by the high-voltage line based on the linear frequency modulation pulse signal, and preprocess the original echo signal to obtain a preprocessed echo signal;

[0119] The signal-to-noise ratio enhancement module 300 is configured to perform pulse compression processing on the linear frequency modulation pulse signal and the pre-processed echo signal in the frequency domain to obtain a frequency domain pulse compression signal;

[0120] The target distance calculation module 400 is configured to obtain the target distance based on the frequency domain pulse pressure signal.

[0121] The present embodiment proposes a millimeter-wave radar-based high-voltage line detection and ranging system, which is used to implement the aforementioned millimeter-wave radar-based high-voltage line detection and ranging method. Therefore, the specific implementation methods of the millimeter-wave radar-based high-voltage line detection and ranging system can be seen in the embodiment part of the aforementioned millimeter-wave radar-based high-voltage line detection and ranging method. For example, the pulse signal transmission module 100, the echo signal acquisition and preprocessing module 200, the signal-to-noise ratio enhancement module 300 and the target distance calculation module 400 are respectively used to implement steps S1, S2, S3 and S4 in the millimeter-wave radar-based high-voltage line detection and ranging method in Example 1. Therefore, its specific implementation methods can refer to the descriptions of the corresponding embodiments of each part. In order to avoid redundancy, they will not be repeated here.

[0122] Example 3

[0123] The present invention also provides a power transmission line alarm device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. The device is characterized in that when the processor executes the program, the steps of the high-voltage line detection and ranging method based on millimeter-wave radar described in Example 1 are implemented to obtain the target distance between the operator and the target high-voltage line, and obtain the safe operating distance based on the target distance.

[0124] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0125] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0126] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0128] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A high-voltage line detection and ranging method based on millimeter-wave radar, characterized in that: The following steps are involved: S1: Transmits linear frequency modulation pulse signal to the high-voltage line area; S2: acquiring an original echo signal reflected by the target high-voltage line based on the linear frequency modulation pulse signal, and preprocessing the original echo signal to obtain a preprocessed echo signal; S3: performing pulse compression processing on the linear frequency modulation pulse signal and the preprocessed echo signal in the frequency domain to obtain a frequency domain pulse compression signal; S4: Obtaining a target distance based on the frequency-domain pulse pressure signal, including: S41: After performing moving target detection processing on the frequency domain pulse pressure signal, setting a first number of iterations and a second number of iterations; S42: Determine whether the first number of iterations has been reached: If not, return to step S2 to perform non-coherent accumulation to obtain the non-coherent accumulation value calculated in each iteration; If yes, filter out the maximum value among the multiple non-coherent accumulation values ​​and obtain the target distance information corresponding to the maximum value; S43: Determine whether the second number of iterations has been reached: If not, return to step S2 to obtain the target distance information corresponding to the maximum value in each non-coherent accumulation iterative calculation process; If so, cluster the target distance information corresponding to multiple maximum values ​​to obtain the target distance.

2. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 1 is characterized in that: The linear frequency modulation pulse signal r(t',n) is: Where t′=t-nT represents the intra-pulse time, i.e., the fast time, in seconds, rect represents the rectangular function operation, t is the acquisition time, n=0,...,N-1, N is the number of accumulated pulses, T p is the pulse width, T is the pulse repetition period, k is the modulation frequency of the transmitting signal, f c is the carrier frequency.

3. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 1 is characterized in that: The original echo signal s(t',n) is expressed as: s(t',n)=A r r[t'-τ(t),n]+w(t',n) in, v is the lifting speed of the vehicle arm, A r represents the echo amplitude in volts, w(t′,n) represents Gaussian white noise with a mean of 0, R(t) represents the distance between the radar and the target high-voltage line at time t, in meters, R0 represents the distance between the radar and the target high-voltage line at the initial time t0, and c represents the electromagnetic wave propagation speed, which is 3×10 8 Meters / second.

4. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 3 is characterized in that: In S2, the steps for obtaining the pre-processed echo signal are as follows: S21: performing pulse cancellation processing on the original echo signal to obtain an echo signal after pulse cancellation processing; S22: performing interference suppression on the echo signal after the pulse cancellation processing to obtain an interference-suppressed echo signal, that is, the pre-processed echo signal.

5. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 4 is characterized in that: The echo signal s after the pulse cancellation process MTI (t',n) is: s MTI (t',n)=s(t',n)-2s(t'-T,n)+s(t'-2T,n)。 6. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 5, characterized in that: The pre-processed echo signal S(f′,n) is: S(f′,n)=FFT[s MTI (t',n)] Among them, f′∈[-f d ,f d ], v is the lifting speed of the vehicle arm, in m / s; FFT[·] represents the fast Fourier transform function.

7. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 6, characterized in that: The frequency domain pulse pressure signal s pc (t',n) is: s pc (t',n)=IFFT[FFT[r(t',n)]S * (f′,n)] Among them, S * (f′, n) represents the conjugate of the preprocessed echo signal S(f′, n), and IFFT[·] represents an inverse fast Fourier transform function.

8. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 7, characterized in that: In S42, the non-coherent accumulation value s obtained by each iteration is obtained. Q (t',n) is: Wherein, MTD[·] represents a moving target detection function, and Q is the first number of iterations.

9. The high-voltage line detection and ranging method based on millimeter-wave radar according to claim 8, characterized in that: In S42, the target distance information R1 corresponding to the maximum value is obtained as: Among them, s Q (t',n) represents the non-coherent accumulation value, T s Indicates the collection time interval in seconds.

10. A high-voltage line detection and ranging system based on millimeter-wave radar, characterized in that: To implement the steps of the high-voltage line detection and ranging method based on millimeter-wave radar as described in claim 1, the system includes the following modules: A pulse signal transmitting module is used to transmit a linear frequency modulation pulse signal to the high-voltage line area; An echo signal acquisition and preprocessing module is used to acquire an original echo signal reflected by the high-voltage line based on the linear frequency modulation pulse signal, and preprocess the original echo signal to obtain a preprocessed echo signal; a signal-to-noise ratio enhancement module, configured to perform pulse compression processing on the linear frequency modulation pulse signal and the preprocessed echo signal in the frequency domain to obtain a frequency domain pulse compression signal; The target distance calculation module is used to obtain the target distance based on the frequency domain pulse pressure signal.

11. A power transmission line alarm device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the high-voltage line detection and ranging method based on millimeter-wave radar are implemented to obtain the target distance between the operator and the target high-voltage line, and obtain the safe working distance according to the target distance.

Images