Micro-rain radar interference suppression method

Abstract

The invention discloses a micro-rain radar interference filtering method, which comprises the following steps of: firstly, setting a binarization threshold value, carrying out binarization processing on a distance Doppler spectrum observed by a micro-rain radar, and then detecting a connected region of a binarization result of the distance Doppler observation spectrum of the micro-rain radar; the method comprises the following steps of: selecting an effective non-interference signal spectrum, calculating a variable coefficient of a connected region area, setting a threshold value of a non-interference signal spectrum connected region, screening the effective non-interference signal spectrum, and finally reserving data of an effective non-interference signal spectrum region to realize interference suppression of the micro-rain radar, so that the interference suppression of the micro-rain radar is realized under variable meteorological conditions and complex interference environments. The anti-interference performance of the micro-rain radar can be remarkably enhanced, so that the detection accuracy of the meteorological target is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of meteorological radar monitoring, and in particular relates to a light rain radar interference suppression method. Background Art

[0002] The micro-rain radar transmits and receives microwave signals to measure the echo signals of precipitation particles in the atmosphere, thereby obtaining information such as precipitation intensity, precipitation rate and precipitation type. In addition, the micro-rain radar can provide vertical profile information of precipitation, including the distribution height, velocity and particle size distribution of precipitation particles, which is of great significance for studying precipitation processes, cloud physical processes and climate change. Since the micro-rain radar can monitor the precipitation process in real time, it has important applications in short-term forecasting, and also provides important data support for studying scientific issues such as atmospheric dynamics, cloud microphysical processes, precipitation mechanisms and climate change.

[0003] However, with the widespread application of electronic equipment, the electromagnetic environment is becoming increasingly complex. When observing, the light rain radar is easily interfered by its electronic equipment or other light rain radars. Therefore, how to effectively identify and eliminate these interferences from radar observation data has become an important issue to improve the performance of light rain radar. At present, there is no relevant report on the interference suppression technology for light rain radar. Summary of the invention

[0004] The purpose of the present invention is to propose a light rain radar interference suppression method, which realizes interference suppression by processing the radar range Doppler spectrum, thereby improving the reliability of light rain radar observation data and the accuracy of inversion results.

[0005] The technical solution to achieve the purpose of the present invention is as follows: In a first aspect, the present invention provides a method for suppressing interference of a light rain radar, comprising the following steps:

[0006] Step 1: Set the binarization threshold and perform binarization on the range Doppler spectrum observed by the light rain radar;

[0007] Step 2: Detect the connected areas of the binarization results of the light rain radar range Doppler observation spectrum;

[0008] Step 3: Calculate the coefficient of variation of the connected area and set the threshold of the connected area of ​​the non-interference signal spectrum to achieve the screening of effective non-interference signal spectrum;

[0009] Step 4: Keep the data in the effective non-interference signal spectrum area to achieve light rain radar interference suppression.

[0010] In a second aspect, the present invention provides a light rain radar interference suppression system for implementing the method described in the first aspect, the system comprising:

[0011] The first module is used to set the binarization threshold and perform binarization processing on the range Doppler spectrum observed by the light rain radar;

[0012] The second module is used to detect the connected areas of the binarization results of the light rain radar range Doppler observation spectrum;

[0013] The third module is used to calculate the coefficient of variation of the area of ​​the connected region and set the threshold of the connected region of the non-interference signal spectrum to achieve the screening of the effective non-interference signal spectrum;

[0014] The fourth module retains the data of the effective non-interference signal spectrum area to achieve light rain radar interference suppression.

[0015] In a third aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method described in the first aspect when executing the program.

[0016] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0017] In a fifth aspect, the present invention provides a computer program product, comprising a computer program, which implements the steps of the method described in the first aspect when executed by a processor.

[0018] Compared with the prior art, the present invention has the following significant advantages: 1) by performing hierarchical interference analysis and suppression processing on radar signals, the present method significantly improves the signal-to-noise ratio and the accuracy of target detection, and greatly enhances the anti-interference performance of the light rain radar under changeable meteorological conditions and complex interference environments; 2) the present method implements interference suppression before the radar system performs digital signal processing, which facilitates its integration into existing Doppler radars or other types of light rain radar systems, thereby improving the reliability and efficiency of the radar in practical applications, and has extremely high practical value in the field of meteorological monitoring and forecasting.

[0019] The present invention is further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the iterative algorithm flow chart of the light rain radar interference filtering method.

[0021] Figure 2 This is the light rain radar range Doppler map without filtering the effectively connected area.

[0022] Figure 3 It is the light rain radar range Doppler map filtered by the effective connected area. DETAILED DESCRIPTION

[0023] In order to solve the problems existing in the prior art, the present invention provides a light rain radar interference suppression method to improve the reliability and accuracy of data, which is applicable to various light rain radar systems, including Doppler radar and other types of meteorological observation radars.

[0024] like Figure 1 As shown, a method for suppressing interference of a light rain radar of the present invention comprises the following steps:

[0025] Step 1: Set the binarization threshold and perform binarization on the range Doppler spectrum observed by the light rain radar, specifically:

[0026] Step 1-1: For each height h of the range Doppler spectrum, the amplitude value D h The size of is sorted, expressed as

[0027] Step 1-2: From the sorted data Select the M values ​​with the lowest amplitude value from the set

[0028] Step 1-3: Calculate the average value of these M values ​​as the binarization threshold. The calculation formula is as follows:

[0029]

[0030] Step 1-4: Use threshold T h Binarize the height value to generate a binary image B h , where the binarization process is defined as:

[0031]

[0032] D h (x,y) represents the amplitude value when the speed is x and the distance is y.

[0033] B h (x,y) means when D h (x,y) is greater than the threshold T h Time to B h (x,y) is assigned 1, otherwise it is assigned B h (x,y) is assigned 0, and the resulting binary matrix is ​​obtained.

[0034] Step 2: Detect the connected areas of the binarization results of the light rain radar range Doppler observation spectrum, specifically:

[0035] Step 2-1: Select a point p(x1,y1,z1) with velocity x1, distance y1, and amplitude z1 on the range Doppler spectrum;

[0036] Step 2-2: Initialize a queue Q and add point p to the queue. The queue is used to store all pixels to be checked.

[0037] Step 2-3: Execute the loop until the queue Q is empty. In each loop, perform the following operations: Take a point q from the queue and check the neighboring pixels of point q in all eight directions (up, down, left, right, upper left, lower left, upper right, lower right).

[0038] Step 2-4: For each adjacent pixel, check whether the pixel belongs to the target area and has not been visited. If the pixel meets the conditions (i.e., its value is 1 and has not been marked as visited), add it to the queue Q and mark it as visited.

[0039] Step 2-5: Repeat steps 2-3 until there are no more pixels in queue Q.

[0040] Step 3: Calculate the coefficient of variation of the connected area and set the threshold of the connected area of ​​the non-interfering signal spectrum to screen the effective signal spectrum, specifically:

[0041] Step 3-1: Calculate the mean μ and standard deviation σ of the areas of all connected regions;

[0042] Step 3-2: Calculate the coefficient of variation CV of the connected area = σ μ ;

[0043] Step 3-3: Set the threshold of the connected area of ​​the non-interference signal spectrum to μ×λ(CV);

[0044] Step 3-4: Screen the effective signal spectrum region R whose area of ​​the non-interference signal spectrum connected region is larger than μ×λ(CV).

[0045] Step 4: Retain the data in the effective signal spectrum area to achieve light rain radar interference suppression, specifically:

[0046] Step 4-1: extract the part of the original graph D where the binary area is zero and merge it with the screened effective signal spectrum area R to obtain a signal spectrum image after removing interference;

[0047] Step 4-2: Assign an average value to the interference part to complete the light rain radar interference suppression.

[0048] Based on the same inventive concept, the present invention also provides a light rain radar interference suppression system, comprising:

[0049] The first module is used to set the binarization threshold and perform binarization processing on the range Doppler spectrum observed by the light rain radar;

[0050] The second module is used to detect the connected areas of the binarization results of the light rain radar range Doppler observation spectrum;

[0051] The third module is used to calculate the coefficient of variation of the area of ​​the connected region and set the threshold of the connected region of the non-interference signal spectrum to achieve the screening of the effective non-interference signal spectrum;

[0052] The fourth module retains the data of the effective non-interference signal spectrum area to achieve light rain radar interference suppression.

[0053] The specific implementation methods of the above modules are the same as the steps of the aforementioned light rain radar interference suppression method, and the present invention will not repeat them again.

[0054] The present invention is described in detail below with reference to the embodiments.

[0055] Example

[0056] Initialize a 64×64 matrix to store data, read data, and convert the read string data into numeric data. The average value of each height is calculated to be 3000, which is used as the binarization threshold and the range Doppler spectrum observed by the light rain radar is binarized. The seed filling algorithm is defined for connected area analysis, the size of the input binary image is obtained, each pixel is traversed, and the seed filling algorithm is used to detect 13 connected areas of the binarization result of the range Doppler observation spectrum of the light rain radar. The coefficient of variation of the area of ​​the connected area is calculated to be 2.93. The λ dynamic adjustment rule based on CV is set, and the threshold of the connected area of ​​the non-interference signal spectrum is calculated to be 11.91. The valid connected areas are initially screened, and the upper limit of the area of ​​the invalid area and the dynamic area threshold are set to 2. The connected areas initially judged to be invalid are re-evaluated, and 12 valid connected areas are found, and there is 1 invalid connected area. The area information in the stats array is used to print the areas of valid and invalid connected areas, initialize the screened binary image, retain the valid connected areas, retain the values ​​that are not in the connected areas in the original image, create an image to show the validity of the connected areas, visualize the binary image and highlight the invalid areas, and draw the screened XYZ three-dimensional image.

[0057] Figure 2 This is the range Doppler map of light rain radar without effective connected area screening. Figure 3 This is the range Doppler map of the light rain radar screened by the effective connected area. It can be seen from the figure that the interference is effectively suppressed.

[0058] In summary, the present invention enhances the anti-interference capability of the light rain radar by performing interference suppression processing on the range Doppler spectrum before the radar system performs signal processing.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit it, and the parts not described in detail are common knowledge of ordinary technicians in the field. The protection scope of the present invention shall be based on the content of the claims, and any equivalent changes based on the technical enlightenment of the present invention are also within the protection scope of the present invention.

Claims

1. A method for suppressing interference of light rain radar, characterized in that: The following steps are involved: Step 1: Set the binarization threshold and perform binarization on the range Doppler spectrum observed by the light rain radar; Step 2: Detect the connected areas of the binarization results of the light rain radar range Doppler observation spectrum; Step 3: Calculate the coefficient of variation of the connected area and set the threshold of the connected area of ​​the non-interference signal spectrum to achieve the screening of effective non-interference signal spectrum; Step 4: Keep the data in the effective non-interference signal spectrum area to achieve light rain radar interference suppression.

2. The method according to claim 1, characterized in that The setting of the binarization threshold in step 1 is to perform binarization processing on the range Doppler spectrum observed by the light rain radar, specifically: Step 1-1: For each height h of the range Doppler spectrum, the amplitude value D h The size of is sorted, expressed as Step 1-2: From the sorted data Select the M values ​​with the lowest amplitude value from the set Step 1-3: Calculate the average value of these M values ​​as the binarization threshold. The calculation formula is as follows: Step 1-4: Use threshold T h Binarize the height value to generate a binary image B h , where the binarization process is defined as: D h (x,y) represents the amplitude value when the speed is x and the distance is y; B h (x,y) means when D h (x,y) is greater than the threshold T h Time to B h (x,y) is assigned 1, otherwise it is assigned B h (x,y) is assigned 0, and the resulting binary matrix is ​​obtained.

3. The method according to claim 1, characterized in that The connected area of ​​the binarization result of the light rain radar range Doppler observation spectrum detected in step 2 is specifically: Step 2-1: Select a point p(x1,y1,z1) with a velocity of x1, a distance of y1, and an amplitude of z1 on the range Doppler spectrum; Step 2-2: Initialize a queue Q and add point p to the queue. The queue is used to store all pixels to be checked. Step 2-3: Execute a loop until the queue Q is empty; in each loop, perform the following operations: take a point q from the queue and check the neighboring pixels of point q in all eight directions; Step 2-4: For each adjacent pixel, check whether the pixel belongs to the target area and has not been visited. If the pixel meets the conditions, add it to the queue Q and mark it as visited; Step 2-5: Repeat steps 2-3 until there are no more pixels in queue Q.

4. The method according to claim 3, characterized in that In step 2-4, a pixel meets the condition if the pixel value is 1 and is not marked as visited.

5. The method according to claim 1, characterized in that The calculation of the coefficient of variation of the area of ​​the connected region and setting the threshold of the connected region of the non-interference signal spectrum described in step 3 to achieve the screening of the effective signal spectrum includes the following steps: Step 3-1: Calculate the mean μ and standard deviation σ of the areas of all connected regions; Step 3-2: Calculate the coefficient of variation CV of the connected area = μ ; σ Step 3-3: Set the threshold of the connected area of ​​the non-interference signal spectrum to μ×λ(CV); Step 3-4: Screen the effective signal spectrum region R whose area of ​​the non-interference signal spectrum connected region is larger than μ×λ(CV).

6. The method according to claim 1, characterized in that Step 4: retaining data in the valid signal spectrum region includes the following steps: Step 4-1: extract the part of the binary area in the original graph D that is zero and merge it with the screened effective signal spectrum area R to obtain a signal spectrum image after removing interference; Step 4-2: Assign an average value to the interference part to complete the light rain radar interference suppression.

7. A light rain radar interference suppression system, characterized in that: For implementing the method described in any one of claims 1 to 6, the system comprises: The first module is used to set the binarization threshold and perform binarization processing on the range Doppler spectrum observed by the light rain radar; The second module is used to detect the connected areas of the binarization results of the light rain radar range Doppler observation spectrum; The third module is used to calculate the coefficient of variation of the area of ​​the connected region and set the threshold of the connected region of the non-interference signal spectrum to achieve the screening of the effective non-interference signal spectrum; The fourth module retains the data of the effective non-interference signal spectrum area to achieve light rain radar interference suppression.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 1 to 6 are implemented.

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

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method described in any one of claims 1 to 6 are implemented.

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