An adaptive processing method for co-frequency interference applied to shipborne navigation radar

Abstract

This invention discloses an adaptive processing method for co-channel interference applied to shipborne navigation radar. The method first divides each echo into segments of equal sample length and obtains the mean amplitude and flatness measure of each segment. Second, it obtains the number of interferences for each echo, the start and end points of each interference, and acquires the bottom noise of each echo. Next, it obtains the statistical characteristics of the number, length, and intensity of interferences, and in the frequency domain, obtains the statistical characteristics of the bottom noise of the echoes. Finally, based on the analysis of the interference characteristics, new waveform adjustment parameters are calculated. This invention, through omnidirectional detection, analyzes the time-frequency characteristics and statistical properties of co-channel interference, enabling the shipborne radar to adaptively select waveform parameters to achieve active interference avoidance, reduce the impact of interference, and ensure the perception robustness of the shipborne radar under co-channel interference conditions.

Description

Technical Field

[0001] This invention relates to the field of shipborne navigation radar, and in particular to an adaptive processing method for co-frequency interference applied to shipborne navigation radar. Background Technology

[0002] Shipborne navigation radar is installed on various types of vessels to detect various objects around the vessel, such as ships, bridge piers, embankments, islands, and coastlines. It provides the crew with relatively intuitive and clear target distance and location information, and issues early warning messages as needed to avoid dangerous obstacles, prevent collisions, and ensure the vessel can navigate normally and safely.

[0003] With the development of the shipping industry, shipborne navigation radar, as an important device for ship obstacle avoidance, navigation, and guidance, is becoming increasingly numerous. In ports and other areas with high concentrations of ships, not only are there many vessels, but navigation radars are also densely packed. Although shipborne radars have the ability to adjust waveforms via frequency agility, the limited bandwidth and scarce spectrum resources of the frequency bands they use mean that shipborne radars often operate at similar frequencies, leading to mutual interference between radars operating on the same frequency band.

[0004] When multiple ships are equipped with navigation radars of the same type or standard, the transmitted signals are received directly or indirectly by the interfered radar. Because the interference energy is stronger than the reflected signal energy, 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, in-band noise still exists. The presence of a large amount of in-band interference noise raises the signal noise floor, which not only reduces the signal-to-noise ratio of the reflected signal but also easily drowns out small target signals, leading to false detections, misdetections, or even loss of sensing function.

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

[0006] While time-domain processing offers limited performance improvement, its good real-time performance makes it popular in practical applications. For example, the most common engineering method is the zero-reduction method, which detects the location of interference affecting a signal sequence and converts it to zero in the time domain. Further methods include sliding windowing, regression, and interpolation. Although these methods are simple, they have the following drawbacks: firstly, they remove some useful signal, affecting the signal-to-noise ratio of the useful signal; secondly, when the interference lasts for a long time, the processing effect deteriorates or even becomes ineffective.

[0007] Signal processing methods (including compressed sensing, wavelet analysis, and short-time Fourier transform) have been employed in some studies. These methods can achieve good results under certain conditions, but they suffer from high computational costs and stringent requirements. For example, separating interference and target signals using the sparsity characteristics of different transform domains is effective, but it doesn't perform well under low signal-to-noise ratio conditions. Wavelet analysis of the signal characteristics of interference and target signals can be used to suppress interference, but selecting suitable wavelet basis functions is a challenge. Additionally, using the short-time Fourier transform domain to create a time-frequency plot and obtaining beat frequency interpolation through autoregression and phase matching can suppress interference, but this type of method is computationally intensive.

[0008] In recent years, due to the significant achievements of deep learning in signal processing, deep learning-based methods have been proposed for interference suppression. For example, the patent document "A Deep Learning-Based Method for Suppressing Co-channel Asynchronous Interference in Shipborne Radar" (application number CN202211058304.4) discloses a deep learning-based method for suppressing co-channel asynchronous interference in shipborne radar. This method establishes interference-enabled and interference-free models of the shipborne radar, generates training data, constructs a suppression network model for training, and then suppresses interference on real-time data. However, this method relies on model generation for data, and although it has a theoretical basis, it is difficult to meet the diverse and numerous co-channel interference situations in practical applications. It is only suitable for suppressing small amounts of simple co-channel interference.

[0009] In summary, the above methods all adopt the idea of ​​passively suppressing interference. However, shipborne radar needs to perform omnidirectional detection, and the interference it receives is more varied and requires more diverse and complex processing. Therefore, relying on passive interference suppression is difficult to meet the application requirements of shipborne radar. Summary of the Invention

[0010] The purpose of this invention is to overcome the shortcomings and deficiencies of the prior art and provide an adaptive processing method for co-channel interference applied to shipborne navigation radar. This method analyzes the time-frequency characteristics and statistical properties of co-channel interference through omnidirectional detection, enabling the shipborne radar to adaptively select waveform parameters to achieve active interference avoidance, reduce the impact of interference, and ensure the perception robustness of shipborne radar under co-channel interference conditions.

[0011] The objective of this invention is achieved through the following technical solution:

[0012] An adaptive method for handling co-channel interference applied to shipborne navigation radar includes the following steps:

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

[0014] S2. Quickly locate the co-frequency interference of the echoes of several chirps, obtain the interference quantity of each echo, accurately obtain the starting point and ending point of each interference through coarse and fine localization, and obtain the bottom noise of each echo through frequency domain transformation.

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

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

[0017] Step S1 specifically includes:

[0018] S1-1, Obtain Echo sample point sequence of Chirp ,in, The number of rotations. Let the number of chirps emitted per rotation be the index of the number of rotations. The index of the Chirp to be emitted each rotation ;

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

[0020] S1-3, Cutting sub-segment echo :

[0021] ;

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

[0023] S1-4, Calculation Sub-section Amplitude mean measure :

[0024] ;

[0025] S1-5, Calculation Sub-section flatness measure :

[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 so, store and Otherwise, execute S1-3.

[0030] Step S2 specifically includes:

[0031] S2-1, Order , , and ,in This is an interference flag;

[0032] S2-2, Order Number of interferences Total number of interferences ;

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

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

[0035] S2-5, Determine if the condition is met. If yes, execute S2-6; otherwise, execute S2-8.

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

[0037] S2-7, Starting point for detecting interference ;

[0038] S2-8, Endpoint for detecting interference ;

[0039] S2-9, Determine if the condition is met. 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, to Perform frequency domain transformation to obtain ;

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

[0045] ;

[0046] ;

[0047] Among them, symbols The floor symbol is used for rounding down. It is the frequency domain The One frequency point;

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

[0049] Step S2-7 specifically involves:

[0050] S2-7-1, Let the index ;

[0051] S2-7-2, Calculate the first Two adjacent sample points at each frequency point , The difference : ;

[0052] S2-7-3, Determine if the condition is met. ,in To detect the window length of the sliding window at the interference start point, if

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

[0054] S2-7-4, Determine if the condition is met. ,in To determine the interference start threshold, if it is, execute S2-7-6; otherwise, execute S2-7-5.

[0055] S2-7-5, Obtain Execute S2-8;

[0056] S2-7-6, Order Determine whether the condition is met. If yes, execute S2-7-2; otherwise, execute S2-7-7.

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

[0058] Steps S2-8 specifically refer to:

[0059] S2-8-1, Let the index ;

[0060] S2-8-2, Calculate the first Two adjacent sample points at each frequency point , The difference : ;

[0061] S2-8-3, Determine if the condition is met. If yes, execute S2-8-4; otherwise, execute S2-8-6; where The window length of the sliding window for detecting the endpoint of interference;

[0062] S2-8-4, Determine if the condition is met. If yes, execute S2-8-6; otherwise, execute S2-8-5; where To interfere with the endpoint 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] Step S3 specifically includes:

[0067] Initialize, let ;

[0068] S3-1, Calculate the... Number of Chirp Interference :

[0069] ;

[0070] S3-2, Calculate the first The length of the chirp affected by the interference :

[0071] ;

[0072] S3-3, Calculate the... Chirp interference intensity :

[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 disturbances in Chirp :

[0078] , ;

[0079] in, This is for retrieving the maximum value.

[0080] S3-7, Calculate the total interference length The maximum length of the disturbance in Chirp :

[0081] , ;

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

[0083] , ;

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

[0085] , .

[0086] Step S4 specifically includes:

[0087] The current waveform parameters of the radar are: bandwidth Starting frequency Transmission power Chirp scan duration ;

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

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

[0090] S4-3, Determine if the condition is met. or If yes, execute S4-4; otherwise, execute S4-5. This is the threshold for the total interference length. The maximum interference length threshold;

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

[0092] S4-5, Determine if the condition is met. or If yes, execute S4-6; otherwise, execute S4-7. This is the threshold for the total number of interferences. This is the threshold for the maximum number of interferences;

[0093] S4-6. Obtain a new starting frequency ;

[0094] S4-7, Determine if the condition is met. or If yes, execute S4-8; otherwise, execute S4-9, where... This is the threshold for total interference intensity. The threshold is the maximum interference intensity.

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

[0096] S4-9, Determine if the condition is met. or or If yes, execute S4-10; otherwise, , and Chirp is emitted as a parameter;

[0097] S4-10, Update radar waveform parameters, Let ,or ,or ,Will , and Chirp is emitted as a parameter.

[0098] Step S4-4 specifically involves:

[0099] S4-4-1, Determine if the condition is met. If yes, execute S4-4-2; otherwise, execute S4-4-3.

[0100] S4-4-2, Calculate the slope angle : ,in, For arctangent calculation, The total interference length scaling factor;

[0101] S4-4-3, Calculate the slope angle : ,in, 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, There is redundancy in the slope angle;

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

[0105] Steps S4-6 specifically involve:

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

[0107] S4-6-2, Calculate the update frequency : ,in The scaling factor is the total number of interferences.

[0108] S4-6-3 Calculate the update frequency : , The scaling factor is the maximum number of disturbances.

[0109] S4-6-4, Judgment If yes, execute S4-6-5; otherwise, execute S4-6-6. The maximum starting frequency;

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

[0111] S4-6-6, Storage .

[0112] Steps S4-8 specifically involve:

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

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

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

[0116] S4-8-4, Judgment If yes, execute S4-8-5; otherwise, execute S4-8-6. This is the maximum transmission power;

[0117] S4-8-5, Order ,in Minimum transmission power;

[0118] S4-8-6, Storage .

[0119] Meanwhile, this invention provides:

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

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

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

[0123] 1. This invention adopts an active method of adjusting the transmitted waveform, which overcomes the shortcomings of passive interference suppression methods in dealing with complex and diverse interference, 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-channel interference in the environment or the degree of interference in a certain direction, the interference is adjusted and evaluated simultaneously, so that the radar can automatically obtain better transmission parameters to avoid interference.

[0125] 3. The method of the present invention assesses the degree of influence by obtaining the statistical characteristics of mutual interference in the surrounding environment. The obtained characteristic parameters have low computational complexity and can meet the requirements of real-time processing in practical applications. Attached Figure Description

[0126] Figure 1 This is a flowchart of the co-frequency interference adaptive processing method applied to shipborne navigation radar according to the present invention. Detailed Implementation

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

[0128] according to Figure 1 As shown in the example, this invention provides an adaptive processing method for co-channel interference applied to shipborne navigation radar. This method can actively and adaptively change the waveform of the shipborne navigation radar to reduce the impact of co-channel interference, and includes the following steps:

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

[0130] S2. Quickly locate the co-frequency interference of the echoes of several chirps, obtain the interference quantity of each echo, accurately obtain the starting point and ending point of each interference through coarse and fine localization, and obtain the bottom noise of each echo through frequency domain transformation.

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

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

[0133] Step S1 specifically includes:

[0134] S1-1, Obtain Echo sample point sequence of Chirp ,in, The number of rotations. Let the number of chirps emitted per rotation be the index of the number of rotations. The index of the Chirp to be emitted each rotation In this embodiment, , The radar rotates omnidirectionally 10 times, transmitting 10 chirps each time. After receiving all the echoes, they are converted from analog to digital signals and then processed. For example, This is the digital signal sequence of the first Chirp echo during the first rotation.

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

[0136] S1-3, Cutting 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-section Amplitude mean measure :

[0141] ;

[0142] In this embodiment, , ,get ;

[0143] S1-5, Calculation Sub-section flatness measure :

[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 The number of sub-segments; in this embodiment, ,when hour, , If not, proceed to S1-3.

[0148] S1-7, Order , ,judge If yes, execute S1-8; otherwise, execute S1-3. In this embodiment, , ,when , season , ,because If not, proceed to S1-3.

[0149] S1-8, Order , ,judge If so, store and Otherwise, execute S1-3. In this embodiment, , , ,when season , , If not, proceed to S1-3.

[0150] Step S2 specifically includes:

[0151] S2-1, Order , , and ,in This is an interference flag;

[0152] S2-2, Order Number of interferences Total number of interferences ;

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

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

[0155] S2-5, Determine if the condition is met. If yes, execute S2-6; otherwise, execute S2-8.

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

[0157] S2-7, Starting point for detecting interference ;

[0158] S2-8, Endpoint for detecting interference ;

[0159] S2-9, Determine if the condition is met. 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, to Perform frequency domain transformation to obtain ;

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

[0165] ;

[0166] ;

[0167] Among them, symbols The floor symbol is used for rounding down. It is the frequency domain The One frequency point;

[0168] In this embodiment, , ,but

[0169] ;

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

[0171] Step S2-7 specifically involves:

[0172] S2-7-1, Let the index ;

[0173] S2-7-2, Calculate the first Two adjacent sample points at each frequency point , The difference : In this embodiment, when , , , but ;

[0174] S2-7-3, Determine if the condition is met. ,in To detect the window length of the sliding window at the interference start point, if

[0175] Yes, execute S2-7-4; otherwise, execute S2-7-6. In this embodiment, ,when Execute S2-7-4.

[0176] S2-7-4, Determine if the condition is met. ,in To determine the interference start threshold, if it is, 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 Determine whether the condition is met. If yes, execute S2-7-2; otherwise, execute S2-7-7. In this embodiment, , , ,make ,Right now This is not valid; therefore, execute S2-7-7.

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

[0182] Steps S2-8 specifically refer to:

[0183] S2-8-1, Let the index ;

[0184] S2-8-2, Calculate the first Two adjacent sample points at each frequency point , The difference : In this embodiment, when hour, , , ;

[0185] S2-8-3, Determine if the condition is met. If yes, execute S2-8-4; otherwise, execute S2-8-6; where To prevent interference with the endpoint detection sliding window's window length; in this embodiment, ,when At that time, execute S2-8-4;

[0186] S2-8-4, Determine if the condition is met. If yes, execute S2-8-6; otherwise, execute S2-8-5; where To interfere with the endpoint threshold;

[0187] In this embodiment, , , ,but

[0188] ;

[0189] Therefore, execute S2-8-6.

[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] Step S3 specifically includes:

[0195] Initialize, let ;

[0196] S3-1, Calculate the... Number of Chirp Interference :

[0197] ;

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

[0199] .

[0200] S3-2, Calculate the first The length of the chirp affected by the interference :

[0201] ;

[0202] In this embodiment, , At that time, the length of the 8th chirp affected by the interference is:

[0203] .

[0204] S3-3, Calculate the... Chirp interference intensity :

[0205] ;

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

[0207] .

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

[0209] ;

[0210] In this embodiment, when , At that time, the echo bottom noise of the 8th chirp was:

[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 disturbances in Chirp :

[0215] , ;

[0216] in, This is for retrieving the maximum value.

[0217] In this embodiment, when At that time, the total number of interferences received by the radar is:

[0218] ,

[0219] The maximum number of interferences is:

[0220] .

[0221] S3-7, Calculate the total interference length The maximum length of the disturbance in Chirp :

[0222] , ;

[0223] In this embodiment, when At that time, the total number of interferences received by the radar is:

[0224] ,

[0225] The maximum length affected by interference is:

[0226] .

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

[0228] , ;

[0229] In this embodiment, when At that time, the total interference intensity experienced by the radar is:

[0230] .

[0231] The maximum value of the interference intensity is:

[0232] .

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

[0234] , .

[0235] In this embodiment, when At that time, the total bottom noise experienced by the radar is:

[0236] ;

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

[0238] ;

[0239] Step S4 specifically includes:

[0240] The current waveform parameters of the radar are: bandwidth Starting frequency Transmission power Chirp scan duration In this embodiment, the current waveform parameters are: , , , .

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

[0242] S4-2, Determine if the condition is met. or If yes, execute S4-3; otherwise, , and Chirp is emitted as a parameter, where This is the total noise floor threshold. The maximum noise floor threshold is used; in this embodiment, , , , , ,but Execute S4-3.

[0243] S4-3, Determine if the condition is met. or If yes, execute S4-4; otherwise, execute S4-5. This is the threshold for the total interference length. The maximum interference length threshold is used; in this embodiment, , , , ,Although, ,but Therefore, execute S4-4.

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

[0245] S4-5, Determine if the condition is met. or If yes, execute S4-6; otherwise, execute S4-7. This is the threshold for the total number of interferences. This is the threshold for the maximum number of interferences; in this embodiment, , , , , , Execute S4-6.

[0246] S4-6. Obtain a new starting frequency ;

[0247] S4-7, Determine if the condition is met. or If yes, execute S4-8; otherwise, execute S4-9, where... This is the threshold for total interference intensity. The threshold is the maximum interference intensity; in this embodiment, , , , , , Execute S4-8.

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

[0249] S4-9, Determine if the condition is met. or or If yes, execute S4-10; otherwise, , and Chirp is emitted as a parameter; in this embodiment... , , Execute S4-10;

[0250] S4-10, Update radar waveform parameters, Let ,or ,or ,Will , and Chirp is emitted as a parameter.

[0251] Step S4-4 specifically involves:

[0252] S4-4-1, Determine if the condition is met. If yes, execute S4-4-2; otherwise, execute S4-4-3. In this embodiment, , , , , , , Therefore, execute S4-4-2.

[0253] S4-4-2, Calculate the slope angle : ,in, For arctangent calculation, The total interference length scaling factor;

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

[0255] S4-4-3, Calculate the slope angle : ,in, 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, To avoid slope and angle redundancy; in this embodiment , ,but .

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

[0261] In this embodiment, , ,but:

[0262] .

[0263] Steps S4-6 specifically involve:

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

[0265] S4-6-2, Calculate the update frequency : ,in This is a scaling factor for the total number of interferences; in this embodiment, , , Update the starting frequency .

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

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

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

[0269] S4-6-6, Storage .

[0270] Steps S4-8 specifically involve:

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

[0272] S4-8-2, Calculate the update power : ,in, This is the scaling factor for the total interference intensity; in this embodiment, , , Update power .

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

[0274] S4-8-4, Judgment If yes, execute S4-8-5; otherwise, execute S4-8-6. This is the maximum transmission power; in this embodiment, , , Execute S4-8-6.

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

[0276] S4-8-6, Storage .

[0277] Meanwhile, this embodiment provides:

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

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

[0280] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A co-channel interference adaptive processing method for shipborne navigation radar, characterized in that, Includes the following steps: S1. Perform statistical characteristic analysis on the echoes of several rotations and several chirps, divide each echo into sub-segments of equal sample length, and obtain the mean amplitude measure and flatness measure of each sub-segment. S2. Quickly locate the co-frequency interference of the echoes of several chirps, obtain the interference quantity of each echo, accurately obtain the starting point and ending point of each interference through coarse and fine localization, and obtain the bottom noise of each echo through frequency domain transformation. S3. In the time domain, obtain the statistical characteristics of the number of interferences, interference length, and interference intensity; in the frequency domain, obtain the statistical characteristics of the bottom noise of the echo. S4. Based on the statistical characteristics including the number of interferences, interference length, interference intensity, and noise characteristics, calculate new waveform adjustment parameters to reduce the impact of co-channel interference on the overall performance of the radar. Step S4 specifically includes: The current waveform parameters of the radar are: bandwidth Starting frequency Transmission power Chirp scan duration ; S4-1. Initialize new radar waveform parameters: new Chirp scan duration new starting frequency New transmission power ; S4-2, Determine if the condition is met. or If yes, execute S4-3; otherwise, , and Chirp is emitted as a parameter, where This is the total noise floor threshold. This is the maximum noise floor threshold; For total bottom noise, This represents the maximum bottom noise value in Chirp. S4-3, Determine if the condition is met. or If yes, execute S4-4; otherwise, execute S4-5. This is the threshold for the total interference length. The maximum interference length threshold; The total interference length, This represents the maximum length of the chirp affected by interference. S4-4. Obtain the new Chirp scan duration ; ,in, It is the tangent function. The slope angle, For bandwidth; S4-5, Determine if the condition is met. or If yes, execute S4-6; otherwise, execute S4-7. This is the threshold for the total number of interferences. This is the threshold for the maximum number of interferences; This represents the total number of interferences. This represents the maximum number of disturbances in the Chirp. S4-6. Obtain a new starting frequency ; Steps S4-6 specifically involve: S4-6-1, Judgment If yes, execute S4-6-2; otherwise, execute S4-6-3. S4-6-2, Calculate the update frequency : ,in The scaling factor is the total number of interferences. S4-6-3 Calculate the update frequency : , The scaling factor is the maximum number of disturbances. S4-6-4, Judgment If yes, execute S4-6-5; otherwise, execute S4-6-6. The maximum starting frequency; S4-6-5, Order ,in The minimum starting frequency; S4-6-6, Storage ; S4-7, Determine if the condition is met. or If yes, execute S4-8; otherwise, execute S4-9, where... This is the threshold for total interference intensity. The threshold is the maximum interference intensity. The total interference intensity, This represents the maximum disturbance intensity experienced by the Chirp. S4-8, Obtaining new transmission power ; Steps S4-8 specifically involve: S4-8-1, Judgment If yes, execute S4-8-2; otherwise, execute S4-8-3. S4-8-2, Calculate the update power : ,in, The scaling factor is the total interference intensity. S4-8-3, Calculate the update power : ,in The scaling factor is the maximum interference intensity. S4-8-4, Judgment If yes, execute S4-8-5; otherwise, execute S4-8-6. This is the maximum transmission power; S4-8-5, Order ,in Minimum transmission power; S4-8-6, Storage ; S4-9, Determine if the condition is met. or or If yes, execute S4-10; otherwise, , and Chirp is emitted as a parameter; S4-10, Update radar waveform parameters, Let ,or ,or ,Will , and Chirp is emitted as a parameter.

2. The adaptive processing method for co-channel interference applied to shipborne navigation radar according to claim 1, characterized in that, Step S1 specifically includes: S1-1, Obtain Echo sample point sequence of Chirp ,in, The number of rotations. Let the number of chirps emitted per rotation be the index of the number of rotations. The index of the Chirp to be emitted each rotation ; S1-2, to Segmentation, sub-segment index ; S1-3, Cutting sub-segment echo : ； in, for The number of sample points in the sub-segment; S1-4, Calculation Sub-section Amplitude mean measure : ； S1-5, Calculation Sub-section flatness measure : ； S1-6, Order ,judge If yes, execute S1-7; otherwise, execute S1-3, where... for The number of sub-segments; S1-7, Let div=1 , ,judge If yes, execute S1-8; otherwise, execute S1-3. S1-8, Order , ,judge If so, store and Otherwise, execute S1-3.

3. The adaptive processing method for co-channel interference applied to shipborne navigation radar according to claim 2, characterized in that, Step S2 specifically includes: S2-1, Order , , and ,in This is an interference flag; S2-2, Order Number of interferences Total number of interferences ; S2-3, Judgment If yes, execute S2-4; otherwise, execute S2-11, where... This is the first measurement threshold; S2-4, Judgment If yes, execute S2-5; otherwise, execute S2-11, where... This is the second measure threshold; S2-5, Determine if the condition is met. If yes, execute S2-6; otherwise, execute S2-8. S2-6, Order , , , and ; S2-7, Starting point for detecting interference ; S2-8, Endpoint for detecting interference ; S2-9, Determine if the condition is met. 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, to Perform frequency domain transformation to obtain ; S2-14 Calculate the echo sample point sequence Frequency domain amplitude measurement and bottom noise : ； ； Among them, symbols The floor symbol is used for rounding down. It is the frequency domain The One frequency point; S2-15, Order , ,judge If so, then store each echo. Number of interferences Each interference start point and end point , and background noise Otherwise, execute S2-2.

4. The adaptive processing method for co-channel interference applied to shipborne navigation radar according to claim 3, characterized in that, Step S2-7 specifically involves: S2-7-1, Let the index ; S2-7-2, Calculate the first Two adjacent sample points at each frequency point , The difference : ; S2-7-3, Determine if the condition is met. ,in To detect the window length of the sliding window at the interference start point, if Yes, execute S2-7-4; otherwise, execute S2-7-6. S2-7-4, Determine if the condition is met. ,in To determine the interference start threshold, if it is, execute S2-7-6; otherwise, execute S2-7-5. S2-7-5, Obtain Execute S2-8; S2-7-6, Order Determine whether the condition is met. If yes, execute S2-7-2; otherwise, execute S2-7-7. S2-7-7, Order Execute S2-8.

5. The adaptive processing method for co-channel interference applied to shipborne navigation radar according to claim 3, characterized in that, Steps S2-8 specifically refer to: S2-8-1, Let the index ; S2-8-2, Calculate the first Two adjacent sample points at each frequency point , The difference : ; S2-8-3, Determine if the condition is met. If yes, execute S2-8-4; otherwise, execute S2-8-6; where The window length of the sliding window for detecting the endpoint of interference; S2-8-4, Determine if the condition is met. If yes, execute S2-8-6; otherwise, execute S2-8-5; where To interfere with the endpoint threshold; S2-8-5, Obtain 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 adaptive processing method for co-channel interference applied to shipborne navigation radar according to claim 3, characterized in that, Step S3 specifically includes: Initialize, let ; S3-1, Calculate the... Number of Chirp Interference : ； S3-2, Calculate the interference length of the chi-th Chirp. : ； S3-3, Calculate the interference intensity of the chi-th Chirp. : ； S3-4. Calculate the echo bottom noise of the chi-th 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 disturbances in Chirp : ， ； in, This is for retrieving the maximum value. S3-7, Calculate the total interference length The maximum length of the disturbance in Chirp : ， ； S3-8. Calculate the total interference intensity The maximum value of the disturbance intensity in Chirp : ， ； S3-9, Calculate the total bottom noise and the maximum bottom noise in Chirp : ， 。 7. The adaptive processing method for co-channel interference applied to shipborne navigation radar according to claim 1, characterized in that, Step S4-4 specifically involves: S4-4-1, Determine if the condition is met. If yes, execute S4-4-2; otherwise, execute S4-4-3. S4-4-2, Calculate the slope angle : ,in, For arctangent calculation, The total interference length scaling factor; S4-4-3, Calculate the slope angle : ,in, The maximum interference length scaling factor; S4-4-4, Judgment If yes, execute S4-4-5; otherwise, execute S4-4-6. S4-4-5、 ,in, There is redundancy in the slope angle; S4-4-6. Obtain and store the new scan duration. ,in, It is the tangent function.

8. A server, the server comprising a processor and a memory, characterized in that, The memory stores at least one program, which is loaded and executed by the processor to implement the co-channel interference adaptive processing method for shipborne navigation radar as described in any one of claims 1 to 7.

9. A computer-readable storage medium storing at least one program, characterized in that, The program is loaded and executed by a processor to implement the co-frequency interference adaptive processing method for shipborne navigation radar as described in any one of claims 1 to 7.

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