Same-frequency interference adaptive processing method applied to shipborne navigation radar

Abstract

The invention discloses a same-frequency interference adaptive processing method applied to a shipborne navigation radar, and the method comprises the steps: dividing each echo into sub-segments with equal sample lengths, and obtaining the amplitude mean value measurement and the flatness value measurement of each sub-segment; secondly, obtaining the interference number of each echo, the starting point and the ending point of each interference, and obtaining the bottom noise of each echo; thirdly, obtaining statistical characteristics of interference quantity, interference length and interference intensity, and obtaining bottom noise statistical characteristics of echoes in a frequency domain; and finally, calculating a new waveform adjustment parameter according to the analysis of the interference characteristics. Through omnidirectional detection and analysis of time-frequency characteristics and statistical characteristics of same-frequency interference, the shipborne radar adaptively selects waveform parameters to realize active interference avoidance, the influence of interference is reduced, and a guarantee is provided for perception robustness of the shipborne radar under the condition of same-frequency interference.

Description

Technical Field

[0001] The present invention relates to the field of shipborne navigation radars, and in particular to a method for adaptively processing co-frequency interference applied to shipborne navigation radars. Background Art

[0002] Shipborne navigation radar is installed on various types of ships to detect various objects around the ship, such as ships, bridge piers, embankments, islands, coastlines, etc., providing the crew with more intuitive and clear target distance and direction information, and issuing early warning messages as needed to avoid dangerous obstacles, prevent collision accidents, and ensure the normal and safe navigation of the ship.

[0003] With the development of the shipping industry, shipborne navigation radars, essential equipment for obstacle avoidance, navigation, and guidance, are increasingly common. In densely populated areas like ports, not only are there many ships, but navigation radars are also densely populated. Although shipborne radars have frequency agility to adjust their waveforms, the limited bandwidth and spectrum resources of the frequency bands used by shipborne radars often result in similar frequencies. This can lead to mutual interference between shipborne radars operating in the same frequency band.

[0004] When multiple ships are equipped with the same type or standard of navigation radar, the transmitted signal is directly or indirectly received by the radar being interfered with. Because the interference energy is stronger than the reflected signal, after mixing, a pulse-like signal is generated at the intermediate frequency (IF). This signal introduces a large amount of broadband noise in the frequency domain. Although some noise outside the IF bandwidth can be filtered out using filters, in-band noise still exists. This large amount of in-band interference noise raises the signal noise floor, not only reducing the signal-to-noise ratio of the reflected signal but also easily drowning out tiny target signals, leading to false detections, misdetection, and even perception failure.

[0005] In terms of dealing with co-frequency interference, commonly used methods include three categories: time domain fast processing, signal processing methods and deep learning methods.

[0006] While time-domain processing offers limited performance improvements, it has gained significant attention in practical applications due to its real-time performance. For example, the most commonly used zeroing method in engineering involves detecting locations where interference has affected a signal sequence and converting these locations to zero in the time domain. Other methods include sliding windows, regression, and interpolation. While simple, these methods also have drawbacks: First, they remove some useful signals, affecting the signal-to-noise ratio; second, when interference persists for extended periods, the processing effectiveness deteriorates or even becomes ineffective.

[0007] Some research has used signal processing methods (including compressed sensing, wavelet analysis, and short-time Fourier transforms). While these methods can achieve good results under certain conditions, they also suffer from high computational complexity and stringent requirements. For example, they exploit the sparsity of interference and target signals in different transform domains to separate them, but this approach is ineffective at low signal-to-noise ratios. Wavelet analysis can be used to analyze the signal characteristics of both interference and target signals and then suppress the interference signal, but selecting appropriate wavelet basis functions is challenging. Alternatively, time-frequency mapping can be performed in the short-time Fourier transform domain, where beat frequency interpolation is obtained through autoregression and phase matching to suppress interference. However, these methods are computationally intensive.

[0008] In recent years, due to the good results achieved by deep learning in signal processing, deep learning-based methods have also been proposed for interference suppression. For example, the patent document "A method for suppressing co-frequency asynchronous mutual interference of shipborne radars based on deep learning" (application number CN202211058304.4) discloses a method for suppressing co-frequency asynchronous mutual interference of shipborne radars based on deep learning. By establishing models of shipborne radars with and without interference, training data is generated, a suppression network model is constructed for training, and then mutual interference suppression is performed on real-time data. However, although the data of this method depends on model generation and has a theoretical basis, it is difficult to meet the diverse and large-scale co-frequency interference situations in actual applications and is only suitable for a small amount of simple co-frequency interference suppression.

[0009] From the above analysis, it can be seen that the above methods all adopt the idea of ​​passive interference suppression. However, shipborne radar needs to perform omnidirectional detection, the interference received is more variable, and the processing required is more diverse and complex. Therefore, relying on passive interference suppression processing is difficult to adapt to the application requirements of shipborne radar. Summary of the Invention

[0010] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and provide a method for adaptively processing co-channel interference applied to shipborne navigation radar. The method analyzes the time-frequency characteristics and statistical properties of co-channel interference through omnidirectional detection, enables the shipborne radar to adaptively select waveform parameters to achieve active interference avoidance, reduce the impact of interference, and provide protection for the perception robustness of the shipborne radar in the case of co-channel interference.

[0011] The purpose of the present invention is achieved through the following technical solutions:

[0012] A method for adaptively processing co-channel interference applied to a shipborne navigation radar comprises the following steps:

[0013] S1. Analyze the statistical characteristics of the echoes of several rotations and several chirps, divide each echo into sub-segments of equal sample length, and obtain the amplitude mean measure and flatness measure of each sub-segment;

[0014] S2. Rapidly locate co-frequency interference on multiple chirp echoes to obtain the interference amount for each echo. Through coarse and fine positioning, accurately obtain the starting and ending points of each interference, and obtain the bottom noise of each echo through frequency domain transformation.

[0015] S3. Obtain statistical characteristics of interference quantity, interference length, and interference intensity in the time domain; obtain statistical characteristics of the bottom noise of the echo in the frequency domain;

[0016] S4. Calculate new waveform adjustment parameters based on statistical characteristics such as the number of interferences, interference length, interference intensity, and noise characteristics to reduce the impact of co-frequency interference on the overall performance of the radar.

[0017] The step S1 is specifically as follows:

[0018] S1-1. Acquisition Chirp echo sample point sequence ,in, is the number of rotations, For the number of Chirps emitted per rotation, let the rotation index , the index of the Chirp emitted for each rotation ;

[0019] S1-2, yes Segmentation, its sub-segment index ;

[0020] S1-3, interception Sub-segment echo :

[0021] ;

[0022] in, for The number of sample points in the sub-segment;

[0023] S1-4, calculation sub-segment The amplitude mean measure :

[0024] ;

[0025] S1-5, calculation sub-segment Flatness measure of :

[0026] ;

[0027] S1-6, Order ,judge : If yes, execute S1-7, otherwise execute S1-3, where for The number of sub-segments;

[0028] S1-7, Order , ,judge : If yes, execute S1-8, otherwise execute S1-3;

[0029] S1-8, Order , ,judge : If yes, store and , otherwise, execute S1-3.

[0030] The step S2 is specifically as follows:

[0031] S2-1, Order , , and ,in It is an interference sign;

[0032] S2-2, Order The number of interferences , the total number of interfered ;

[0033] S2-3. Judgment If yes, execute S2-4, otherwise execute S2-11, where is the first measurement threshold;

[0034] S2-4. Judgment If yes, execute S2-5, otherwise execute S2-11, where is the second measurement threshold;

[0035] S2-5. Determine whether If yes, execute S2-6, otherwise execute S2-8;

[0036] S2-6, Order , , , and ;

[0037] S2-7. Starting point for interference detection ;

[0038] S2-8. Detecting the end point of interference ;

[0039] S2-9, determine whether it is satisfied If yes, execute S2-10, otherwise, execute S2-3;

[0040] S2-10, Order ;

[0041] S2-11, Order ,judge If yes, execute S2-12, otherwise execute S2-3;

[0042] S2-12, Order , ,judge If yes, execute S2-13, otherwise, execute S2-2;

[0043] S2-13, yes Perform frequency domain transformation to obtain ;

[0044] S2-14. Calculate the echo sample point sequence Frequency domain amplitude measure of and bottom noise :

[0045] ;

[0046] ;

[0047] Among them, the symbol is the floor symbol, It is the frequency domain No. frequency points;

[0048] S2-15, Order , ,judge If so, store each echo Number of interferences , each interference starting point and end point , , and background noise , otherwise, execute S2-2.

[0049] The step S2-7 is specifically as follows:

[0050] S2-7-1, Order Index ;

[0051] S2-7-2, calculate the Two sample points adjacent to each other 、 The difference : ;

[0052] S2-7-3, determine whether it is satisfied ,in is the window length of the sliding window for interference starting point detection, if

[0053] If yes, execute S2-7-4; otherwise, execute S2-7-6.

[0054] S2-7-4, determine whether it is satisfied ,in Is the interference starting threshold, if yes, execute S2-7-6, otherwise execute S2-7-5;

[0055] S2-7-5, obtain , execute S2-8;

[0056] S2-7-6, Order , to determine whether If yes, execute S2-7-2, otherwise, execute S2-7-7;

[0057] S2-7-7, Order , execute S2-8.

[0058] The step S2-8 is specifically as follows:

[0059] S2-8-1, index ;

[0060] S2-8-2, calculate the Two sample points adjacent to each other 、 The difference : ;

[0061] S2-8-3. Determine whether If yes, execute S2-8-4, otherwise execute S2-8-6; The length of the sliding window for interference endpoint detection;

[0062] S2-8-4, determine whether it is satisfied If yes, execute S2-8-6, otherwise execute S2-8-5; is the interference end threshold;

[0063] S2-8-5, obtain , execute S2-9;

[0064] S2-8-6, Order ,judge If yes, execute S2-8-2, otherwise, execute S2-8-7;

[0065] S2-8-7, , execute S2-9.

[0066] The step S3 is specifically as follows:

[0067] Initialize, let ;

[0068] S3-1. Calculate the The number of Chirp interferences :

[0069] ;

[0070] S3-2, calculate the The length of the interference of a Chirp :

[0071] ;

[0072] S3-3, calculate the Chirp interference strength :

[0073] ;

[0074] S3-4, calculate the Chirp echo bottom noise :

[0075] ;

[0076] S3-5, Order ,judge If yes, execute S3-6, otherwise execute S3-1;

[0077] S3-6. Calculate the total number of interferences The maximum number of interferences in Chirp :

[0078] , ;

[0079] in, To obtain the maximum value operation;

[0080] S3-7. Calculate the total interference length and the maximum interference length in Chirp :

[0081] , ;

[0082] S3-8. Calculate the total interference intensity The maximum interference intensity in Chirp :

[0083] , ;

[0084] S3-9. Calculate the total bottom noise and the maximum value of the bottom noise in the Chirp :

[0085] , .

[0086] The step S4 is specifically as follows:

[0087] The radar waveform parameters at the current moment are: bandwidth , starting frequency , transmit power and Chirp scan duration ;

[0088] S4-1. Initialize new radar waveform parameters: new Chirp scan duration , the new starting frequency , the new transmission power ;

[0089] S4-2. Determine whether or If yes, execute S4-3, otherwise, f and As a parameter, a Chirp is emitted, where is the total noise floor threshold, is the maximum noise floor threshold;

[0090] S4-3. Determine whether or If yes, execute S4-4, otherwise execute S4-5, where is the total interference length threshold, is the maximum interference length threshold;

[0091] S4-4. Get new Chirp scan duration ;

[0092] S4-5. Determine whether or If yes, execute S4-6, otherwise execute S4-7, where is the total interference threshold, is the maximum interference threshold;

[0093] S4-6. Get new starting frequency ;

[0094] S4-7, determine whether it is satisfied or If yes, execute S4-8, otherwise execute S4-9, where is the total interference intensity threshold, is the maximum interference intensity threshold;

[0095] S4-8, obtain new transmission power ;

[0096] S4-9, determine whether it is satisfied or or If yes, execute S4-10, otherwise , and Emit Chirp as a parameter;

[0097] S4-10, update the radar waveform parameters, let ,or ,or ,Will , and Emits a Chirp as a parameter.

[0098] The step S4-4 is specifically as follows:

[0099] S4-4-1. Determine whether If yes, execute S4-4-2, otherwise, execute S4-4-3;

[0100] S4-4-2. Calculate the slope angle : ,in, To calculate the inverse tangent, is the total interference length expansion factor;

[0101] S4-4-3. Calculate the slope angle : ,in, is the maximum interference length scaling factor;

[0102] S4-4-4, Judgment If yes, execute S4-4-5, otherwise, execute S4-4-6;

[0103] S4-4-5, ,in, is the slope angle redundancy;

[0104] S4-4-6. Obtain and store the new scanning duration ,in, is the tangent function.

[0105] The step S4-6 is specifically as follows:

[0106] S4-6-1. Judgment If yes, execute S4-6-2, otherwise, execute S4-6-3;

[0107] S4-6-2. Calculate update frequency : ,in is the total interference scaling factor;

[0108] S4-6-3. Calculate update frequency : , is the maximum interference number scaling factor;

[0109] S4-6-4, Judgment If yes, execute S4-6-5, otherwise execute S4-6-6, where is the maximum starting frequency;

[0110] S4-6-5, Order ,in is the minimum starting frequency;

[0111] S4-6-6, Storage .

[0112] The step S4-8 is specifically as follows:

[0113] S4-8-1. Judgment If yes, execute S4-8-2, otherwise, execute S4-8-3;

[0114] S4-8-2. Calculate the updated power : ,in, is the total interference intensity scaling factor;

[0115] S4-8-3. Calculate the updated power : ,in is the maximum interference intensity scaling factor;

[0116] S4-8-4, Judgment If yes, execute S4-8-5, if no, execute S4-8-6, where is the maximum transmit power;

[0117] S4-8-5, Order ,in is the minimum transmit power;

[0118] S4-8-6, Storage .

[0119] At the same time, the present invention provides:

[0120] A server includes a processor and a memory, wherein the memory stores at least one program, and the program is loaded and executed by the processor to implement the above-mentioned co-channel interference adaptive processing method applied to shipborne navigation radar.

[0121] A computer-readable storage medium stores at least one program, which is loaded and executed by a processor to implement the above-mentioned co-frequency interference adaptive processing method applied to shipborne navigation radar.

[0122] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0123] 1. The present invention adopts an active method of adjusting the transmission waveform, which overcomes the shortcomings of the passive interference suppression method that it is difficult to cope with complex and diverse interferences, and improves the robustness of shipborne navigation radar perception.

[0124] 2. The method of the present invention adopts an adaptive approach. By evaluating the overall degree of co-frequency interference in the environment or the degree of interference in a certain direction, the radar can automatically obtain better transmission parameters to avoid interference while adjusting and evaluating the interference.

[0125] 3. The method of the present invention evaluates the impact degree by obtaining the statistical characteristics of the co-frequency mutual interference in the surrounding environment. The calculation complexity of the obtained characteristic parameters is low and can meet the requirements of real-time processing in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0126] Figure 1 The present invention is a flowchart of the method for adaptively processing co-channel interference applied to shipborne navigation radar. DETAILED DESCRIPTION

[0127] The present invention will be described in further detail below with reference to the embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0128] according to Figure 1 As shown, an example of the present invention provides an adaptive processing method for co-channel interference applied to a shipborne navigation radar, which can actively and adaptively change the waveform of the shipborne navigation radar to reduce the impact of co-channel mutual interference, including the following steps:

[0129] S1. Analyze the statistical characteristics of the echoes of several rotations and several chirps, divide each echo into sub-segments of equal sample length, and obtain the amplitude mean measure and flatness measure of each sub-segment;

[0130] S2. Rapidly locate co-frequency interference on multiple chirp echoes to obtain the interference amount for each echo. Through coarse and fine positioning, accurately obtain the starting and ending points of each interference, and obtain the bottom noise of each echo through frequency domain transformation.

[0131] S3. Obtain statistical characteristics of interference quantity, interference length, and interference intensity in the time domain; obtain statistical characteristics of the bottom noise of the echo in the frequency domain;

[0132] S4. Calculate new waveform adjustment parameters based on statistical characteristics such as the number of interferences, interference length, interference intensity, and noise characteristics to reduce the impact of co-frequency interference on the overall performance of the radar.

[0133] The step S1 is specifically as follows:

[0134] S1-1. Acquisition Chirp echo sample point sequence ,in, is the number of rotations, For the number of Chirps emitted per rotation, let the rotation index , the index of the Chirp emitted for each rotation In this embodiment, , , that is, the radar rotates omnidirectionally 10 times, emitting 10 chirps each time, and after receiving all the echoes, it is converted into a digital signal through analog-to-digital conversion and enters the processing flow. For example, It is the digital signal sequence of the first Chirp echo in the first rotation.

[0135] S1-2, yes Segmentation, its sub-segment index ;

[0136] S1-3, interception Sub-segment echo :

[0137] ;

[0138] in, for The number of sample points in the sub-segment;

[0139] For example, , ,but .

[0140] S1-4, calculation sub-segment The amplitude mean measure :

[0141] ;

[0142] In this embodiment, , ,get ;

[0143] S1-5, calculation sub-segment Flatness measure of :

[0144] ;

[0145] In this embodiment, when hour, ,but:

[0146] .

[0147] S1-6, Order ,judge : If yes, execute S1-7, otherwise execute S1-3, where for In this embodiment, ,when hour, , If no, execute S1-3.

[0148] S1-7, Order , ,judge : If yes, execute S1-8, otherwise execute S1-3; in this embodiment, , ,when , season , ,because If no, execute S1-3.

[0149] S1-8, Order , ,judge : If yes, store and Otherwise, execute S1-3. In this embodiment, , , ,when season , , If no, execute S1-3.

[0150] The step S2 is specifically as follows:

[0151] S2-1, Order , , and ,in It is an interference sign;

[0152] S2-2, Order The number of interferences , the total number of interfered ;

[0153] S2-3. Judgment If yes, execute S2-4, otherwise execute S2-11, where is the first measurement threshold; in this embodiment, , , , , execute S2-4;

[0154] S2-4. Judgment If yes, execute S2-5, otherwise execute S2-11, where is the second measurement threshold; in this embodiment , , , execute S2-5;

[0155] S2-5. Determine whether If yes, execute S2-6, otherwise execute S2-8;

[0156] S2-6, Order , , , and ;

[0157] S2-7. Starting point for interference detection ;

[0158] S2-8. Detecting the end point of interference ;

[0159] S2-9, determine whether it is satisfied If yes, execute S2-10, otherwise, execute S2-3;

[0160] S2-10, Order ;

[0161] S2-11, Order ,judge If yes, execute S2-12, otherwise execute S2-3;

[0162] S2-12, Order , ,judge If yes, execute S2-13, otherwise, execute S2-2;

[0163] S2-13, yes Perform frequency domain transformation to obtain ;

[0164] S2-14. Calculate the echo sample point sequence Frequency domain amplitude measure of and bottom noise :

[0165] ;

[0166] ;

[0167] Among them, the symbol is the floor symbol, It is the frequency domain No. frequency points;

[0168] In this embodiment, , ,but

[0169] ;

[0170] S2-15, Order , ,judge If so, store each echo Number of interferences , each interference starting point and end point , , and background noise , otherwise, execute S2-2.

[0171] The step S2-7 is specifically as follows:

[0172] S2-7-1, Order Index ;

[0173] S2-7-2, calculate the Two sample points adjacent to each other 、 The difference : In this embodiment, when , , , but ;

[0174] S2-7-3, determine whether it is satisfied ,in is the window length of the sliding window for interference starting point detection, if

[0175] If yes, execute S2-7-4, otherwise execute S2-7-6; in this embodiment, ,when , execute S2-7-4.

[0176] S2-7-4, determine whether it is satisfied ,in Is the interference starting threshold, if yes, execute S2-7-6, otherwise execute S2-7-5;

[0177] In this embodiment, , , ,but

[0178] ;

[0179] S2-7-5, obtain , execute S2-8; for example, according to the embodiment of S2-7-4, .

[0180] S2-7-6, Order , to determine whether If yes, execute S2-7-2, otherwise execute S2-7-7; in this embodiment, , , ,make ,Right now Not true, therefore, execute S2-7-7.

[0181] S2-7-7, Order , execute S2-8.

[0182] The step S2-8 is specifically as follows:

[0183] S2-8-1, index ;

[0184] S2-8-2, calculate the Two sample points adjacent to each other 、 The difference : In this embodiment, when hour, , , ;

[0185] S2-8-3. Determine whether If yes, execute S2-8-4, otherwise execute S2-8-6; is the window length of the interference endpoint detection sliding window; in this embodiment, ,when When , execute S2-8-4;

[0186] S2-8-4, determine whether it is satisfied If yes, execute S2-8-6, otherwise execute S2-8-5; is the interference end threshold;

[0187] In this embodiment, , , ,but

[0188] ;

[0189] Therefore, S2-8-6 is executed.

[0190] S2-8-5, obtain , execute S2-9; in this embodiment, For example, according to the embodiment of S2-8-4, .

[0191] S2-8-6, Order ,judge If yes, execute S2-8-2, otherwise, execute S2-8-7;

[0192] In this embodiment, , , ,make , therefore, execute S2-8-7.

[0193] S2-8-7, , execute S2-9.

[0194] The step S3 is specifically as follows:

[0195] Initialize, let ;

[0196] S3-1. Calculate the The number of Chirp interferences :

[0197] ;

[0198] In this embodiment, , , the number of interferences on the 8th Chirp is:

[0199] .

[0200] S3-2, calculate the The length of the interference of a Chirp :

[0201] ;

[0202] In this embodiment, , When , the interference length of the 8th Chirp is:

[0203] .

[0204] S3-3, calculate the Chirp interference strength :

[0205] ;

[0206] In this embodiment, when , When , the interference intensity of the 8th Chirp is:

[0207] .

[0208] S3-4, calculate the Chirp echo bottom noise :

[0209] ;

[0210] In this embodiment, when , When , the echo bottom noise of the 8th Chirp is:

[0211] ;

[0212] S3-5, Order ,judge If yes, execute S3-6, otherwise execute S3-1;

[0213] In this embodiment, , ,make ,because , execute S3-6.

[0214] S3-6. Calculate the total number of interferences The maximum number of interferences in Chirp :

[0215] , ;

[0216] in, To obtain the maximum value operation;

[0217] In this embodiment, when When , the total amount of interference received by the radar is:

[0218] ,

[0219] The maximum number of interferences is:

[0220] .

[0221] S3-7. Calculate the total interference length and the maximum interference length in Chirp :

[0222] , ;

[0223] In this embodiment, when When , the total amount of interference received by the radar is:

[0224] ,

[0225] The maximum interference length is:

[0226] .

[0227] S3-8. Calculate the total interference intensity The maximum interference intensity in Chirp :

[0228] , ;

[0229] In this embodiment, when When , the total interference intensity received by the radar is:

[0230] .

[0231] The maximum interference intensity is:

[0232] .

[0233] S3-9. Calculate the total bottom noise and the maximum value of the bottom noise in the Chirp :

[0234] , .

[0235] In this embodiment, when When , the total bottom noise received by the radar is:

[0236] ;

[0237] The maximum value of the bottom noise in the Chirp is:

[0238] ;

[0239] The step S4 is specifically as follows:

[0240] The radar waveform parameters at the current moment are: bandwidth , starting frequency , transmit power and Chirp scan duration ; In this embodiment, the current waveform parameters are: , , , .

[0241] S4-1. Initialize new radar waveform parameters: new Chirp scan duration , the new starting frequency , the new transmission power ;

[0242] S4-2. Determine whether or If yes, execute S4-3, otherwise, , and As a parameter, a Chirp is emitted, where is the total noise floor threshold, is the maximum noise floor threshold; in this embodiment, , , , , ,but , execute S4-3.

[0243] S4-3. Determine whether or If yes, execute S4-4, otherwise execute S4-5, where is the total interference length threshold, is the maximum interference length threshold; in this embodiment, , , , ,Although, ,but , so, execute S4-4.

[0244] S4-4. Get new Chirp scan duration ;

[0245] S4-5. Determine whether or If yes, execute S4-6, otherwise execute S4-7, where is the total interference threshold, is the maximum interference quantity threshold; in this embodiment, , , , , , , execute S4-6.

[0246] S4-6. Get new starting frequency ;

[0247] S4-7, determine whether it is satisfied or If yes, execute S4-8, otherwise execute S4-9, where is the total interference intensity threshold, is the maximum interference intensity threshold; in this embodiment, , , , , , , execute S4-8.

[0248] S4-8, obtain new transmission power ;

[0249] S4-9, determine whether it is satisfied or or If yes, execute S4-10, otherwise , and Chirp is transmitted as a parameter; in this embodiment, , , , execute S4-10;

[0250] S4-10, update the radar waveform parameters, let ,or ,or ,Will , and Emits a Chirp as a parameter.

[0251] The step S4-4 is specifically as follows:

[0252] S4-4-1. Determine whether If yes, execute S4-4-2, otherwise, execute S4-4-3; in this embodiment, , , , , , , , so, execute S4-4-2.

[0253] S4-4-2. Calculate the slope angle : ,in, To calculate the inverse tangent, is the total interference length expansion factor;

[0254] In this embodiment, , , , , slope angle .

[0255] S4-4-3. Calculate the slope angle : ,in, is the maximum interference length scaling factor;

[0256] In this embodiment, , , , , the slope angle is:

[0257] .

[0258] S4-4-4, Judgment If yes, execute S4-4-5, otherwise, execute S4-4-6; in this embodiment, , execute S4-4-6.

[0259] S4-4-5, ,in, is the slope angle redundancy; in this embodiment , ,but .

[0260] S4-4-6. Obtain and store the new scanning duration ,in, is the tangent function.

[0261] In this embodiment, , ,but:

[0262] .

[0263] The step S4-6 is specifically as follows:

[0264] S4-6-1. Judgment If yes, execute S4-6-2, otherwise execute S4-6-3; in this embodiment, , , , , , , , so, execute S4-6-2.

[0265] S4-6-2. Calculate update frequency : ,in is the total interference scaling factor; in this embodiment, , , , update the starting frequency .

[0266] S4-6-3. Calculate update frequency : , is the maximum interference number scaling factor; in this embodiment, , , , update the starting frequency .

[0267] S4-6-4, Judgment If yes, execute S4-6-5, otherwise execute S4-6-6, where is the maximum starting frequency; in this embodiment, , , , execute S4-6-6.

[0268] S4-6-5, Order ,in is the minimum starting frequency; in this embodiment, , ,make .

[0269] S4-6-6, Storage .

[0270] The step S4-8 is specifically as follows:

[0271] S4-8-1. Judgment If yes, execute S4-8-2, otherwise, execute S4-8-3; in this embodiment, , , , , , , , so, execute S4-8-3;

[0272] S4-8-2. Calculate the updated power : ,in, is the total interference strength scaling factor; in this embodiment, , , , update power .

[0273] S4-8-3. Calculate the updated power : ,in is the maximum interference intensity scaling factor; in this embodiment, , , , update power .

[0274] S4-8-4, Judgment If yes, execute S4-8-5, if no, execute S4-8-6, where is the maximum transmission power; in this embodiment, , , , execute S4-8-6.

[0275] S4-8-5, Order ,in is the minimum transmission power; in this embodiment, , ,make .

[0276] S4-8-6, Storage .

[0277] At the same time, this embodiment provides:

[0278] A server includes a processor and a memory, wherein the memory stores at least one program, and the program is loaded and executed by the processor to implement the above-mentioned co-channel interference adaptive processing method applied to shipborne navigation radar.

[0279] A computer-readable storage medium stores at least one program, which is loaded and executed by a processor to implement the above-mentioned co-frequency interference adaptive processing method applied to shipborne navigation radar.

[0280] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for adaptively processing co-channel interference applied to shipborne navigation radar, characterized in that: The following steps are involved: S1. Analyze the statistical characteristics of the echoes of several rotations and several chirps, divide each echo into sub-segments of equal sample length, and obtain the amplitude mean measurement and flatness measurement of each sub-segment; S2. Rapidly locate the same-frequency interference of several chirp echoes to obtain the interference quantity of each echo. Accurately obtain the starting point and end point of each interference through coarse and fine positioning, and obtain the bottom noise of each echo through frequency domain transformation. S3. In the time domain, obtain the statistical characteristics of the interference quantity, interference length and interference intensity; in the frequency domain, obtain the statistical characteristics of the bottom noise of the echo; S4. Calculate new waveform adjustment parameters based on statistical characteristics such as interference quantity, interference length, interference intensity, and noise characteristics to reduce the impact of co-frequency interference on the overall performance of the radar.

2. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 1, characterized in that: The step S1 is specifically: S1-1. Acquisition Chirp echo sample point sequence ,in, is the number of rotations, The number of chirps emitted per rotation, let the rotation index , the index of the chirp emitted for each rotation ; S1-2, yes Segmentation, its sub-segment index ; S1-3, interception Sub-segment echo : ； in, for The number of sample points in the sub-segment; S1-4, calculation sub-segment The amplitude mean measure : ； S1-5, calculation sub-segment Flatness measure of : ； S1-6, Order ,judge : If yes, execute S1-7, otherwise, execute S1-3, where for The number of sub-segments; S1-7, set div=1 , ,judge : If yes, execute S1-8, otherwise, execute S1-3; S1-8, Order , ,judge : If yes, store and , otherwise, execute S1-3.

3. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 2 is characterized in that: The step S2 is specifically: S2-1. Order , , and ,in It is a sign of interference; S2-2. Order The number of interferences , the total number of interfered ; S2-3. Judgment If yes, execute S2-4, otherwise, execute S2-11, where is the first measurement threshold; S2-4. Judgment If yes, execute S2-5, otherwise, execute S2-11, where is the second measurement threshold; S2-5. Determine whether , if yes, execute S2-6, otherwise, execute S2-8; S2-6, Order , , , and ; S2-7. Starting point of interference detection ; S2-8. Detecting the end point of interference ; S2-9, determine whether it is satisfied , if yes, execute S2-10, otherwise, execute S2-3; S2-10, Order ; S2-11, Order ,judge , if yes, execute S2-12, otherwise, execute S2-3; S2-12, Order , ,judge , if yes, execute S2-13, otherwise, execute S2-2; S2-13, yes Perform frequency domain transformation to obtain ; S2-14. Calculate the echo sample point sequence Frequency domain amplitude measure of and bottom noise : ； ； Among them, the symbol is the floor symbol, It is the frequency domain No. Frequency points; S2-15, Order , ,judge If so, store each echo The number of interferences , each interference starting point and end point , , and background noise , otherwise, execute S2-2.

4. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 3 is characterized in that: The step S2-7 is specifically as follows: S2-7-1, Order Index ; S2-7-2, calculate the Two sample points adjacent to each other , The difference : ; S2-7-3. Determine whether ,in is the window length of the sliding window for interference starting point detection, if If yes, execute S2-7-4; otherwise, execute S2-7-6; S2-7-4. Determine whether ,in is the interference starting point threshold, if yes, execute S2-7-6, otherwise, execute S2-7-5; S2-7-5, Acquisition , execute S2-8; S2-7-6, Order , determine whether , if yes, execute S2-7-2, otherwise, execute S2-7-7; S2-7-7, Order , execute S2-8.

5. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 3 is characterized in that: The step S2-8 is specifically as follows: S2-8-1, Order Index ; S2-8-2, calculate the Two sample points adjacent to each other , The difference : ; S2-8-3. Determine whether If yes, execute S2-8-4, otherwise, execute S2-8-6; The length of the sliding window for interference endpoint detection; S2-8-4. Determine whether If yes, execute S2-8-6, otherwise, execute S2-8-5; is the interference endpoint threshold; S2-8-5, Acquisition , execute S2-9; S2-8-6, Order ,judge , if yes, execute S2-8-2, otherwise, execute S2-8-7; S2-8-7, , execute S2-9.

6. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 3 is characterized in that: The step S3 is specifically: Initialize, let ; S3-1. Calculate the The number of interferences of Chirp : ； S3-2. Calculate the interference length of the chi-th Chirp : ； S3-3. Calculate the chi-th Chirp interference intensity : ； S3-4. Calculate the echo bottom noise of the chirp : ； S3-5, Order ,judge , if yes, execute S3-6, otherwise, execute S3-1; S3-6. Calculate the total number of interferences The maximum number of interferences in Chirp : ， ； in, To obtain the maximum value operation; S3-7. Calculate the total interference length The maximum interference length in Chirp : ， ； S3-8. Calculate the total interference intensity The maximum interference intensity in Chirp : ， ； S3-9. Calculate the total bottom noise The maximum value of the bottom noise in the Chirp : ， 。 7. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 6 is characterized in that: The step S4 is specifically: The radar waveform parameters at the current moment are: bandwidth , starting frequency , transmit power and Chirp scan duration ; S4-1. Initialize new radar waveform parameters: new Chirp scan duration , the new starting frequency , the new transmission power ; S4-2. Determine whether or If yes, execute S4-3, otherwise , and As a parameter, a Chirp is emitted, where is the total noise floor threshold, is the maximum noise floor threshold; S4-3. Determine whether or If yes, execute S4-4, otherwise, execute S4-5, where is the total interference length threshold, is the maximum interference length threshold; S4-4. Get new Chirp scan duration ; S4-5. Determine whether or If yes, execute S4-6, otherwise, execute S4-7, where is the total interference quantity threshold, is the maximum interference quantity threshold; S4-6. Get a new starting frequency ; S4-7. Determine whether or If yes, execute S4-8, otherwise, execute S4-9, where is the total interference strength threshold, is the maximum interference intensity threshold; S4-8. Get new transmission power ; S4-9, determine whether it is satisfied or or If yes, execute S4-10, otherwise , and Emit Chirp as a parameter; S4-10, update radar waveform parameters, let ,or ,or ,Will , and Emits a Chirp as a parameter.

8. The method for adaptively processing co-channel interference applied to shipborne navigation radar according to claim 7, characterized in that: The step S4-4 is specifically as follows: S4-4-1. Determine whether , if yes, execute S4-4-2, otherwise, execute S4-4-3; S4-4-2. Calculate the slope angle : ,in, For the inverse tangent calculation, is the total interference length expansion factor; S4-4-3. Calculate the slope angle : ,in, is the maximum interference length expansion factor; S4-4-4, Judgment , if yes, execute S4-4-5, otherwise, execute S4-4-6; S4-4-5, ,in, is the slope angle redundancy; S4-4-6. Obtain and store new scanning duration ,in, is the tangent function.

9. A server, comprising a processor and a memory, characterized in that: At least one program is stored in the memory, and the program is loaded and executed by the processor to implement the method for adaptively processing co-channel interference applied to shipborne navigation radar as described in any one of claims 1 to 8.

10. A computer-readable storage medium, wherein at least one program is stored in the storage medium, characterized in that: The program is loaded and executed by a processor to implement the method for adaptively processing co-channel interference applied to a shipborne navigation radar as described in any one of claims 1 to 8.

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