Adaptive sea clutter suppression method of navigation radar

Abstract

The invention discloses an adaptive sea clutter suppression method for a navigation radar, and the method comprises the steps: 1, constructing an STC gain function library: constructing the STC gain function library containing a plurality of STC gain functions through adjusting R0 and n values; step 2, selecting a reference bottom noise; 3, counting sea clutters, including the number of the sea clutters and the ultra-high amplitude mean value of the sea clutters; 4, adaptively selecting an STC gain function: adaptively selecting the STC gain function from the step 1 according to the sea clutter counted in the step 3; step 5, calculating gain; step 6, gain conversion; and step 7, sea clutter suppression. According to the method, a reference bottom noise value is obtained based on statistics of an original echo amplitude value of a previous period, and then the number of data points and an average amplitude value of sea clutters are obtained through statistics; different space variable gain control functions are selected through two dimensions of the number of sea clutter data points and the amplitude value, and self-adaptive suppression of sea clutters is achieved.

Description

Technical Field

[0001] The invention relates to the field of radar signal processing, in particular to an adaptive sea clutter suppression method for a navigation radar. Background Art

[0002] Sea surface target detection is an important branch of radar target detection and has significant research value for shore-based monitoring and navigation. However, due to the presence of electromagnetic waves scattered by the sea surface (i.e., sea clutter), the detection and tracking performance of radar is seriously affected. In addition, since the emission signals of small targets are relatively weak, they are easily masked by strong sea clutter, which is particularly obvious when detecting small targets flying low over the sea.

[0003] In view of the dynamic and fluctuating nature of sea clutter, traditional sea clutter suppression algorithms use fixed processing templates and parameters, which makes it difficult to effectively suppress dynamic sea clutter, which may increase the probability of false alarms or cause significant attenuation or even missed detection of nearby target signals. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an adaptive sea clutter suppression method for a navigation radar in view of the deficiencies of the above-mentioned prior art. The adaptive sea clutter suppression method for the navigation radar is based on the statistics of echo videos, can count the sea clutter intensity in real time, and can adaptively select processing parameters to suppress sea clutter, and can effectively cope with the fluctuation of sea clutter.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] An adaptive sea clutter suppression method for a navigation radar comprises the following steps.

[0007] Step 1: Build an STC gain function library: The navigation radar uses spatial variable gain control STC for target detection; the gain function g(R) of STC is expressed as:

[0008]

[0009] In the formula, R 0 is the reference distance.

[0010] R is the distance from the detection target to the radar station.

[0011] n is the function exponent.

[0012] By adjusting R 0 and n values, thereby constructing an STC gain function library containing N STC gain functions; wherein N ≥ 3.

[0013] Step 2: Statistically calculate the baseline noise floor Value_Base.

[0014] Step 3: Count the sea clutter, specifically including the following steps:

[0015] Step 3-1. Calculate C i (j):C i (j) is the mean value of the echo amplitude around the jth scanning point in the i-th scanning direction within B kilometers from the radar station during the current radar scanning cycle; where; B≤5.

[0016] Step 3-2: Count the number of sea clutter SeaClutter_Num: Count each C calculated in step 3-1 i (j) are compared with Value_Base, which will satisfy 2C i (j)>All C of H·Value_Base i (j) Quantity, denoted as SeaClutter_Num; wherein H is a set proportional coefficient not less than 1.

[0017] Step 3-3, calculate the average sea clutter amplitude SeaClutter_AverageVal: SeaClutter_AverageVal is the average echo amplitude exceeding Value_Base around the jth scanning point in the i-th scanning direction.

[0018] Step 4: Adaptively select the STC gain function: According to the number of sea clutter SeaClutter_Num and the average value of the sea clutter super-high amplitude SeaClutter_AverageVal counted in step 3, select the corresponding STC gain function from the STC gain function library in step 1; the smaller the SeaClutter_Num, the higher the R 0 The smaller the R 0 When it remains unchanged, the smaller SeaClutter_AverageVal is, the smaller n is.

[0019] Step 5. Calculate the gain: Use the STC gain function selected in step 4 to calculate the gain g(R) at a distance R from the radar station.

[0020] Step 6: Gain conversion: Convert the gain g(R) calculated in step 6 into decibel db_g(R).

[0021] Step 7, sea clutter suppression: obtain the echo amplitude dbValue(R) at a distance R from the radar station in the current radar scanning cycle, perform STC suppression on dbValue(R), and obtain STC(R). The specific calculation formula is:

[0022] STC(R)=dbValue(R)-db_g(R)

[0023] Where STC(R) is the echo amplitude after STC suppression at a distance R from the radar station in the current radar scanning cycle.

[0024] In step 1, N = a*b+1; where a is the number of 0 = 0 outside R 0 The number of values, b is the number of values ​​of n except n=0, and a≥2, b≥1.

[0025] In step 1, a=3, b=3, N=10, 3 R 0 The values ​​are 1, 3 and 5 respectively; the values ​​of the three n are 2, 5 and 10 respectively; the 10 STC gain functions are:

[0026] Article 1; R 0 =1, n=2; Article 2; R 0 =1, n=5; Article 3; R 0 =1, n=10.

[0027] Article 4; R 0 =3, n=2; Article 5; R 0 =3, n=5; Article 6; R 0 =3, n=10.

[0028] Article 7; R 0 =5, n=2; Article 8; R 0 =5, n=5; Article 9; R 0 =5, n=10.

[0029] Article 10; R 0 =0, n=0.

[0030] In step 3-1, B=3, then in step 4, the method for adaptively selecting the STC gain function is:

[0031] and

[0032] 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select option 1.

[0033] like and

[0034] 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select option 2.

[0035] like and

[0036] 4. Value_Base<SeaClutter_AverageVal, select option 3.

[0037] like and

[0038] 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select option 4.

[0039] like and

[0040] 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select option 5.

[0041] like and

[0042] 4. Value_Base<SeaClutter_AverageVal, select item 6.

[0043] like and

[0044] 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select Article 7.

[0045] like and

[0046] 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select Article 8.

[0047] like and

[0048] 4. Value_Base<SeaClutter_AverageVal, select Article 9.

[0049] like If SeaClutter_AverageVal≤1.5·Value_Base, select Article 10.

[0050] Where Range is the detection distance of the radar.

[0051] R sum The maximum number of scan points per scan direction per radar scan cycle.

[0052] In step 2, the reference noise floor Value_Base is the non-zero minimum value of the radar echo amplitude within A meters at the farthest end of the radar station in the previous radar scanning cycle.

[0053] In step 2, A=100, the method for obtaining Value_Base includes the following steps:

[0054] Step 2-1, obtain D i (j): The echo amplitude D of the jth scanning point in the i-th scanning direction within the current radar scanning cycle and within A = 100 meters from the farthest end of the radar station i (j); where i = 1, 2, K, i sum ,i sum The maximum scanning azimuth value for each radar scanning cycle; Range is the detection distance of the radar; R sum The maximum number of scan points per scan direction per radar scan cycle.

[0055] Step 2-2: D obtained in step 2-1 i (j) Sort and take the lowest non-zero value as the base noise value, denoted as Value_Base.

[0056] In step 3-2, H=1.5.

[0057] In step 3-1, C i The calculation method of (j) comprises the following steps:

[0058] Step 3-1A, Get D i (j): Traverse the echo amplitude D of the jth scanning point in the i-th scanning direction within the current radar scanning cycle within the range of 3 km from the radar station B i (j); where i = 1, 2, K, i sum ; i sum is the maximum scanning azimuth value for each radar scanning cycle; Range is the detection distance of the radar; R sum The maximum number of scan points per scan direction per radar scan cycle.

[0059] Step 3-1B, obtain S i' (j'): for each D i (j), each takes itself as the center, selects m·n scanning points around it, and obtains the radar echo amplitude S of the j'th scanning point on the i'th scanning direction i' (j'); where Both m and n are odd numbers.

[0060] Step 3-1C, calculate Ci (j): For each D i (j) The average value of the radar echo amplitude of the surrounding m·n scanning points is calculated as follows:

[0061]

[0062] In the formula, i=1,2,K,i sum ;

[0063] In step 3-3, the statistical method of SeaClutter_AverageVal includes the following steps:

[0064] Step 3-3A, calculate SeaClutter_Vali(j): for each C i (j) Calculate the difference between it and Value_Base SeaClutter_Val i (j) specifically:

[0065] SeaClutter_Val i (j) = C i (j)-Value_Base

[0066] In the formula, i=1,2,K,i sum ;

[0067] Step 3-3B, calculate SeaClutter_AverageVal, the specific expression is:

[0068]

[0069] In step 6, the calculation formula of db_g(R) is:

[0070] db_g(R)=10·log 10 (g(R)).

[0071] The present invention has the following beneficial effects: the present invention obtains a reference noise floor value based on statistics of the original echo amplitude value of the previous cycle, and then obtains the number of data points and the average amplitude value of the sea clutter by statistics; different spatially variable gain control functions are selected according to the two dimensions of the number of sea clutter data points and the amplitude value, so as to realize adaptive suppression of sea clutter. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A schematic diagram of the radar raw video data in each radar scanning cycle is shown.

[0073] Figure 2A schematic diagram of the location within 100 meters from the farthest end of the radar station and 3 kilometers from the radar station is shown.

[0074] Figure 3 A schematic diagram showing the method of calculating the average echo amplitude using m·n scanning points around each scanning point. DETAILED DESCRIPTION

[0075] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific preferred embodiments.

[0076] In the description of the present invention, it should be understood that the terms "left side", "right side", "upper part", "lower part" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second" and the like do not indicate the importance of the components, and therefore cannot be understood as limiting the present invention. The specific dimensions used in this embodiment are only for illustrating the technical solution, and do not limit the scope of protection of the present invention.

[0077] An adaptive sea clutter suppression method for a navigation radar comprises the following steps.

[0078] Step 1: Build STC gain function library: Navigation radar uses spatial variable gain control STC for target detection.

[0079] The Space-Time Control (STC) method is a technology widely used in radar systems to improve the radar's target detection performance in complex backgrounds. The core idea of ​​STC is to adjust the gain of units at different distances to reduce the signal strength near the radar.

[0080] In radar systems, the attenuation of signal strength with distance R usually follows the inverse square law, that is, the signal strength S is inversely proportional to the square of the distance R. The STC method applies different gains to different distance units at the receiving end to match the signal strength of the long-distance unit with the signal strength of the short-distance unit.

[0081] The gain function g(R) of the above STC is expressed as:

[0082]

[0083] In the formula, R 0 is the reference distance.

[0084] R is the distance from the detection target to the radar station.

[0085] n is the function exponent.

[0086] By adjusting R 0 and n value, thereby constructing an STC gain function library containing N STC gain functions; wherein N ≥ 3, preferably N = a*b+1; wherein a is the number of STC gain functions divided by R 0 = 0 outside R 0 The number of values, b is the number of values ​​of n except n=0, and a≥2, b≥1. In this embodiment, it is further preferred that: a=3, b=3, N=10, 3 R 0 The values ​​are 1, 3 and 5 respectively; the values ​​of the three n are 2, 5 and 10 respectively; the 10 STC gain functions are:

[0087] Article 1; R 0 =1, n=2; Article 2; R 0 =1, n=5; Article 3; R 0 =1, n=10.

[0088] Article 4; R 0 =3, n=2; Article 5; R 0 =3, n=5; Article 6; R 0 =3, n=10.

[0089] Article 7; R 0 =5, n=2; Article 8; R 0 =5, n=5; Article 9; R 0 =5, n=10.

[0090] Article 10; R 0 =0, n=0.

[0091] In the above 10 STC gain functions, R 0 and n values, as shown in the following table.

[0092]

[0093] Step 2: Select the reference noise floor Value_Base: The reference noise floor Value_Base is the non-zero minimum value of the radar echo amplitude within A meters at the farthest end of the radar station in the previous radar scanning cycle.

[0094] In this embodiment, preferably A=100, the method for obtaining Value_Base preferably includes the following steps.

[0095] Step 2-1, obtain D i (j)

[0096] like Figure 1 As shown, the radar raw video data in each radar scanning cycle includes i sum scanning positions, each of which has R sumscanning points. Therefore, it is also called i sum is the maximum scanning azimuth value for each radar scanning cycle; R sum The maximum number of scan points per scan direction per radar scan cycle.

[0097] like Figure 2 As shown, the echo amplitude D of the jth scanning point in the i-th scanning direction is within A = 100 meters from the farthest end of the radar station in the current radar scanning cycle. i (j); where i = 1, 2, K, isum;

[0098] Range is the detection distance of the radar.

[0099] Step 2-2: D obtained in step 2-1 i (j) Sort and take the lowest non-zero value as the base noise value, denoted as Value_Base.

[0100] Step 3: Counting sea clutter, specifically including the following steps.

[0101] Step 3-1. Calculate C i (j): C i (j) is the average value of the echo amplitude around the jth scanning point in the ith scanning direction within B kilometers from the radar station in the current radar scanning cycle; wherein; B≤5, in this embodiment, preferably B=3 kilometers.

[0102] C i The calculation method of (j) preferably includes the following steps.

[0103] Step 3-1A, Get D i (j): Traverse the echo amplitude D of the jth scanning point in the i-th scanning direction within the current radar scanning cycle within the range of 3 km from the radar station B i (j); where i = 1, 2, K, i sum ; i sum is the maximum scanning azimuth value for each radar scanning cycle; Range is the detection distance of the radar; R sum The maximum number of scan points per scan direction per radar scan cycle.

[0104] Step 3-1B, obtain S i' (j'): such as Figure 3 As shown, for each D i (j), each takes itself as the center, selects m·n scanning points around it, and obtains the radar echo amplitude S of the j'th scanning point on the i'th scanning direction i' (j'); where Both m and n are odd numbers.

[0105] Step 3-1C, calculate C i (j): For each D i (j) The average value of the radar echo amplitude of the surrounding m·n scanning points is calculated as follows:

[0106]

[0107] In the formula, i=1,2,K,i sum ;

[0108] Step 3-2: Count the number of sea clutter SeaClutter_Num: Count each C calculated in step 3-1 i (j) are compared with Value_Base, which will satisfy 2C i (j)>All C of H·Value_Base i (j) Number, denoted as SeaClutter_Num; wherein H is a set proportional coefficient not less than 1. In this embodiment, H=1.5 is preferred.

[0109] Step 3-3, calculate the average sea clutter amplitude SeaClutter_AverageVal: SeaClutter_AverageVal is the average echo amplitude exceeding Value_Base around the jth scanning point in the i-th scanning direction.

[0110] The statistical method of SeaClutter_AverageVal preferably includes the following steps.

[0111] Step 3-3A, calculate SeaClutter_Vali(j): for each C i (j) Calculate the difference between it and Value_Base SeaClutter_Val i (j) specifically:

[0112] SeaClutter_Val i (j) = C i (j)-Value_Base

[0113] In the formula, i=1,2,K,i sum ;

[0114] Step 3-3B, calculate SeaClutter_AverageVal, the specific expression is:

[0115]

[0116] Step 4: Adaptively select the STC gain function: According to the number of sea clutter SeaClutter_Num and the average value of the sea clutter super-high amplitude SeaClutter_AverageVal counted in step 3, select the corresponding STC gain function from the STC gain function library in step 1; the smaller the SeaClutter_Num, the higher the R 0 The smaller the R 0 When it remains unchanged, the smaller SeaClutter_AverageVal is, the smaller n is.

[0117] The above method for adaptively selecting the STC gain function is preferably:

[0118] and

[0119] 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select option 1.

[0120] like and

[0121] 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select option 2.

[0122] like and

[0123] 4. Value_Base<SeaClutter_AverageVal, select option 3.

[0124] like and

[0125] 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select option 4.

[0126] like and

[0127] 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select option 5.

[0128] like and

[0129] 4. Value_Base<SeaClutter_AverageVal, select item 6.

[0130] like and

[0131] 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select Article 7.

[0132] like and

[0133] 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select Article 8.

[0134] like and

[0135] 4. Value_Base<SeaClutter_AverageVal, select Article 9.

[0136] like If SeaClutter_AverageVal≤1.5·Value_Base, select Article 10.

[0137] Step 5. Calculate the gain: Use the STC gain function selected in step 4 to calculate the gain g(R) at a distance R from the radar station.

[0138] Step 6, gain conversion: convert the gain g(R) calculated in step 1 into decibel db_g(R), and the calculation formula is preferably:

[0139] db_g(R)=10·log 10 (g(R))

[0140] Step 7, sea clutter suppression: obtain the echo amplitude dbValue(R) at a distance R from the radar station in the current radar scanning cycle, perform STC suppression on dbValue(R), and obtain STC(R). The specific calculation formula is:

[0141] STC(R)=dbValue(R)-db_g(R)

[0142] Where STC(R) is the echo amplitude after STC suppression at a distance R from the radar station in the current radar scanning cycle.

[0143] The preferred embodiments of the present invention are described in detail above; however, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. An adaptive sea clutter suppression method for a navigation radar, characterized in that: The steps include: Step 1: Build an STC gain function library: The navigation radar uses spatial variable gain control STC for target detection; the gain function g(R) of STC is expressed as: Where R0 is the reference distance; R is the distance from the detection target to the radar station; n is the function index; By adjusting the values ​​of R0 and n, an STC gain function library containing N STC gain functions is constructed; wherein N ≥ 3; Step 2: Statistically calculate the baseline noise value Value_Base; Step 3: Count the sea clutter, including the following steps: Step 3-1. Calculate C i (j):C i (j) is the mean value of the echo amplitude around the jth scanning point in the i-th scanning direction within B kilometers from the radar station during the current radar scanning cycle; where; B≤5; Step 3-2: Count the number of sea clutter SeaClutter_Num: Count each C calculated in step 3-1 i (j) are compared with Value_Base, which will satisfy 2C i (j)>All C of H·Value_Base i (j) number, denoted as SeaClutter_Num; where H is a set proportional coefficient not less than 1; Step 3-3, calculate the average value of the sea clutter super-high amplitude SeaClutter_AverageVal: SeaClutter_AverageVal is the average value of the echo amplitude exceeding Value_Base around the jth scanning point in the i-th scanning direction; Step 4, adaptively select the STC gain function: according to the number of sea clutter SeaClutter_Num and the average value of the sea clutter super-high amplitude SeaClutter_AverageVal counted in step 3; select the corresponding STC gain function from the STC gain function library in step 1; wherein, the smaller the SeaClutter_Num, the smaller the R0; when R0 remains unchanged, the smaller the SeaClutter_AverageVal, the smaller n; Step 5, calculate the gain: use the STC gain function selected in step 4 to calculate the gain g(R) at a distance R from the radar station; Step 6, gain conversion: convert the gain g(R) calculated in step 1 into decibel db_g(R); Step 7, sea clutter suppression: obtain the echo amplitude dbValue(R) at a distance R from the radar station in the current radar scanning cycle, perform STC suppression on dbValue(R), and obtain STC(R). The specific calculation formula is: STC(R)=dbValue(R)-db_g(R) Where STC(R) is the echo amplitude after STC suppression at a distance R from the radar station in the current radar scanning cycle.

2. The method for adaptive sea clutter suppression of navigation radar according to claim 1, characterized in that: In step 1, N=a*b+1; wherein a is the number of R0 values ​​except R0=0, b is the number of n values ​​except n=0, and a≥2, b≥1.

3. The method for adaptive sea clutter suppression of navigation radar according to claim 2, characterized in that: In step 1, a=3, b=3, N=10, the three R0 values ​​are 1, 3 and 5 respectively; the three n values ​​are 2, 5 and 10 respectively; the 10 STC gain functions are: Article 1; R0 = 1, n = 2; Article 2; R0 = 1, n = 5; Article 3; R0 = 1, n = 10; Article 4; R0=3, n=2; Article 5; R0=3, n=5; Article 6; R0=3, n=10; Article 7; R0=5, n=2; Article 8; R0=5, n=5; Article 9; R0=5, n=10; Article 10; R0=0, n=0.

4. The method for adaptive sea clutter suppression of navigation radar according to claim 3, characterized in that: In step 3-1, B=3, then in step 4, the method for adaptively selecting the STC gain function is: and 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select the first option; like and 2·Value_Base<SeaClutter_AverageVal≤4·Value_Base, select the second option; like and 4. Value_Base<SeaClutter_AverageVal, select item 3; like and 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select item 4; like and 2. Value_Base<SeaClutter_AverageVal≤4. Value_Base, select item 5; like and 4. Value_Base<SeaClutter_AverageVal, select item 6; like and 1.5·Value_Base<SeaClutter_AverageVal≤2·Value_Base, select Article 7; like and 2. Value_Base<SeaClutter_AverageVal≤4. Value_Base, select Article 8; like and 4. Value_Base<SeaClutter_AverageVal, select Article 9. like and SeaClutter_AverageVal≤1.5·Value_Base, select Article 10; In the formula, Range is the detection distance of the radar; R sum The maximum number of scan points per scan direction per radar scan cycle.

5. The method for adaptive sea clutter suppression of navigation radar according to claim 1, characterized in that: In step 2, the reference noise floor Value_Base is the non-zero minimum value of the radar echo amplitude within A meters at the farthest end of the radar station in the previous radar scanning cycle.

6. The method for adaptive sea clutter suppression of navigation radar according to claim 5, characterized in that: In step 2, A=100, the method for obtaining Value_Base includes the following steps: Step 2-1, obtain D i (j): The echo amplitude D of the jth scanning point in the i-th scanning direction within the current radar scanning cycle and within A = 100 meters from the farthest end of the radar station i (j); where i = 1, 2, K, i sum ,i sum The maximum scanning azimuth value for each radar scanning cycle; Range is the detection distance of the radar; R sum The maximum number of scanning points at each scanning direction for each radar scanning cycle; Step 2-2: D obtained in step 2-1 i (j) Sort and take the lowest non-zero value as the base noise value, denoted as Value_Base.

7. The method for adaptive sea clutter suppression of navigation radar according to claim 1, characterized in that: In step 3-2, H=1.

5.

8. The method for adaptive sea clutter suppression of navigation radar according to claim 1, characterized in that: In step 3-1, C i The calculation method of (j) comprises the following steps: Step 3-1A, Get D i (j): Traverse the echo amplitude D of the jth scanning point in the i-th scanning direction within the current radar scanning cycle within the range of 3 km from the radar station B i (j); where i = 1, 2, K, i sum ; i sum is the maximum scanning azimuth value for each radar scanning cycle; Range is the detection distance of the radar; R sum The maximum number of scanning points at each scanning direction for each radar scanning cycle; Step 3-1B, obtain S i' (j'): for each D i (j), each takes itself as the center, selects m·n scanning points around it, and obtains the radar echo amplitude S of the j'th scanning point on the i'th scanning direction i' (j'); where Both m and n are odd numbers; Step 3-1C, calculate C i (j): For each D i (j) The average value of the radar echo amplitude of the surrounding m·n scanning points is calculated as follows: Wherein, i = 1, 2, K, i sum ; 9. The method for adaptive sea clutter suppression of navigation radar according to claim 8, characterized in that: In step 3-3, the statistical method of SeaClutter_AverageVal includes the following steps: Step 3-3A, calculate SeaClutter_Vali(j): for each C i (j) Calculate the difference between it and Value_Base, SeaClutter_Val i (j) specifically: SeaClutter_Val i (j)=C i (j)-Value_Base In the formula, i=1,2,K,i sum ; Step 3-3B, calculate SeaClutter_AverageVal, the specific expression is:

10. The method for adaptive sea clutter suppression of navigation radar according to claim 1, characterized in that: In step 6, the calculation formula of db_g(R) is: db_g(R)=10·log 10 (g(R))。

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