Refined clutter simulation method for airborne radar under the conditions of fuselage vibration and array element failure

Abstract

The present invention relates to the field of signal processing technology, and provides a method for fine-tuning clutter simulation of airborne radar in the case of fuselage jitter and array element failure. The method comprises: determining the first k The first pulse repetition period during normal operation m The position coordinates of the array elements and the p The phase center of each subarray is calculated to calculate the array gain and subarray gain within the kth pulse repetition period; the gain of each information point in the k The echo signal vector within the pulse repetition period is used to calculate each information point K The echo signal vector of each pulse is calculated; and then the signal vector of the range loop is calculated. The present invention completes the clutter simulation of unmanned aerial vehicle radar under the condition of body vibration and array element failure, and improves the authenticity of clutter simulation. When the working environment of the carrier aircraft is harsh, the clutter simulation of the airborne radar can still be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of signal processing, and in particular to a method for simulating refined clutter of an airborne radar under the conditions of fuselage jitter and array element failure. Background Art

[0002] Airborne radar, with the advantage of an aerial motion platform, effectively overcomes the limitations of the earth's curvature and solves the blind spot problem of ground-based radar in low-altitude detection. At the same time, airborne radar has high flexibility and rapid deployment capabilities, and can respond quickly and be deployed to the required location, so it has received widespread attention and attention from various countries. However, airborne radars are usually in a downward-looking working state, and coupled with their own movement, there will be problems such as wide clutter distribution range, high intensity, and space-time two-dimensional coupling characteristics, which seriously affect the detection performance of the target.

[0003] The study of clutter simulation is of great significance to the design of clutter suppression algorithms. At present, the research on airborne clutter by scholars at home and abroad mainly starts from three aspects: the statistical model of clutter, the mechanism model of clutter physical scattering units, and the clutter model of actual scenes. However, the above clutter simulation research is carried out under the premise that the performance parameters such as the array and the carrier remain constant. In the actual working process, factors such as weather changes, airflow effects, and radar errors can cause fuselage jitter or array element failure, resulting in non-uniform and non-stationary clutter. Therefore, it is urgent to invent an effective clutter simulation model for the occurrence of fuselage jitter and array element failure, which lays the foundation for further research on clutter suppression methods under the conditions of fuselage jitter and array element failure.

[0004] In view of this, overcoming the defects of the prior art is an urgent problem to be solved in the field of this technology. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for fine clutter simulation of airborne radar under the conditions of fuselage jitter and array element failure.

[0006] The present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for fine-tuning clutter simulation of airborne radar under the conditions of fuselage jitter and array element failure, comprising:

[0008] According to the subarray partitioning model, the array is divided into N subarrays, there are a total of K pulses, the ideal position coordinates of the array element are given by , , Three components represent;

[0009] According to the ideal position of the array element, the vibration of the fuselage causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray ;

[0010] According to the array model, k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , calculate the array gain within the kth pulse repetition period and subarray gain , ;

[0011] With the fuselage as the center, the ground is divided N r The distance ring, l The range rings are divided into N l information points, according to the refined clutter model, k Array gain within a pulse repetition period and subarray gain , calculate each information point in the k The echo signal vector within the pulse repetition period ,in For the i The azimuth angle between the information point and the array, i =1,2,...,N l , For the l The range ring and the elevation angle of the array, l =1,2,..., N r ;

[0012] According to each information point in k The echo signal vector within the pulse repetition period , calculate each information point K The echo signal vector of the pulse ;

[0013] Use every information point K The echo signal vector of the pulse , calculate the l The echo signal vector of the range ring .

[0014] Preferably, the array element is located at an ideal position of the array element and the vibration of the fuselage causes the array element to be located at an ideal position of the array element. The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the position coordinates of the mth array element that works normally within the kth pulse repetition period and the phase center of the pth subarray , specifically including:

[0015] Confirm the position coordinates of the mth array element that works normally within the kth pulse repetition period ;

[0016] The phase center of the pth subarray working normally during the kth pulse repetition period ;

[0017] in, The mth array element works normally in the kth pulse repetition period. The deviation of the axis direction from the ideal position, The mth array element works normally in the kth pulse repetition period. The deviation of the axis direction from the ideal position, The mth array element works normally in the kth pulse repetition period. The deviation of the axis direction from the ideal position, is the mth array element that works normally within the kth pulse repetition period when no body vibration occurs. The ideal position in the axial direction, is the mth array element that works normally within the kth pulse repetition period when no body vibration occurs. The ideal position in the axial direction, is the mth array element that works normally within the kth pulse repetition period when no body vibration occurs. The ideal position in the axial direction, For the k The first pulse repetition period during normal operation m The position coordinates of the array elements, For the k The first pulse repetition period p The phase center of each subarray, For the p The number of array elements that are working normally in a sub-array.

[0018] Preferably, according to the array model, the position coordinates of the mth array element that works normally within the kth pulse repetition period are and the phase center of the pth subarray , calculate the array gain within the kth pulse repetition period and subarray gain , specifically including:

[0019] Calculate the array gain within the kth pulse repetition period ;

[0020] Calculate the p-th subarray gain in the k-th pulse repetition period ;

[0021] in, represents the array element gain, represents the maximum antenna gain of the array, represents the maximum antenna gain of the p-th subarray, is the direction vector of the information point, is the array beam pointing direction vector, is the amplitude pattern of a single array element, is the working wavelength.

[0022] Preferably, the method comprises: k Array gain within a pulse repetition period and subarray gain , respectively calculate the echo signal vector of each information point in the kth pulse repetition period , specifically including:

[0023] Calculate the echo signal vector in the kth pulse repetition period ;

[0024] in, represents the random fluctuations introduced by clutter block reflections; Indicates the statistical distribution characteristics of clutter amplitude; represents the normalized noise power; Indicates the peak transmit power of the airborne radar; Indicates the kth pulse repetition period l The distance ring i Array gain in the direction of each information point; Indicates the operating wavelength; Represents the radar cross-section of the clutter block; Indicates pulse pressure benefit; Indicates l The distance ring i The distance between each information point and the array; is the Boltzmann constant; is the Kelvin temperature; is the receiver bandwidth; is the receiver noise factor; is the system loss;

[0025] For the k The first pulse repetition period l The distance ring i The vector formed by the receiving antenna gain of each subarray in the direction of the information point is expressed as ; is the kth pulse repetition period l The distance ring i The spatial steering vector in the direction of the information point is expressed as .

[0026] in For the l The distance ring i The direction vector of the information point.

[0027] Preferably, the echo signal vector of each information point in the kth pulse repetition period , calculate the echo of K pulses at each information point , specifically including:

[0028] Calculate the first l The distance ring i Information points K The echo signal vector of the pulse .

[0029] in is the flight velocity vector of the carrier aircraft, For the l The distance ring i The direction vector of each information point.

[0030] Preferably, the echo signal vector of each information point is used , calculate the l The echo signal vector of the range ring , specifically including:

[0031] Calculate the first l The echo signal vector of the range ring .

[0032] in T is the number of distance blurs, For the The number of information points divided in the distance ring, For the The distance ring i Information points K The echo signal vector of the pulse, is the number of range rings within the maximum unambiguous distance.

[0033] Preferably, in the step of: according to the ideal position of the array element, the vibration of the fuselage causes the array element to be The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray Previously, methods also included:

[0034] Regarding the body shaking phenomenon, determine the body shaking that causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position ;

[0035] In view of the failure of array elements, determine the number of array elements that are working normally .

[0036] Preferably, the fuselage shaking phenomenon is determined by determining that the fuselage shaking causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position , specifically including:

[0037] The vibration of the fuselage causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position Satisfy the first relationship;

[0038] The first relationship is ;

[0039] in represents uniform distribution, , , is the jitter amplitude, is the angular frequency of the jitter, represents the speed of plane simple harmonic wave propagating along the plane, is the initial phase, Indicates time, Indicates that the array element is The coordinates of the ideal position on the axis.

[0040] Preferably, the number of array elements that are normally working is determined according to the array element failure phenomenon. , specifically including:

[0041] When array element failure occurs and the quality of each array element is equal, the working state of a single array element obeys the binomial distribution, which is expressed as ;

[0042] in Indicates The working status of each array element. A value of 0 indicates that the array element is normal, and a value of 1 indicates that the array element fails. represents the probability of array element failure, represents binomial distribution;

[0043] Then the number of array elements that work normally when the array element fails is .

[0044] Preferably, the airborne radar transmitting antenna comprises M rows and N columns, with a total of M q array element;

[0045] The subarrays are synthesized by column. After the fuselage shakes and array element failures occur, the number of array elements that work normally is , No. k The first pulse repetition period m The coordinates of the array element are d mk , the antenna array is divided into N Subarray, p The number of array elements in a normal working subarray is , No. k The first pulse repetition period p The phase center of the subarray is d spk , the number of distance fuzzy times is T, and the number of distance rings within the maximum unfuzzy distance is I , No. l The number of information points divided by the distance ring is N l , the number of pulses for coherent processing is K.

[0046] In a second aspect, the present invention further provides a device for simulating refined clutter of an airborne radar under the condition of fuselage jitter and array element failure, which is used to implement the method for simulating refined clutter of an airborne radar under the condition of fuselage jitter and array element failure described in the first aspect, and the device comprises:

[0047] At least one processor; and a memory in communication with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to execute the method for fine-tuning clutter simulation of airborne radar under the conditions of fuselage jitter and array element failure described in the first aspect.

[0048] In a third aspect, the present invention further provides a non-volatile computer storage medium, wherein the computer storage medium stores computer executable instructions, and the computer executable instructions are executed by one or more processors to complete the method described in the first aspect.

[0049] In a fourth aspect, a chip is provided, comprising: a processor and an interface, for calling and running a computer program stored in the memory from a memory, and executing the method of the first aspect.

[0050] According to a fifth aspect, a computer program product comprising instructions is provided. When the instructions are executed on a computer or a processor, the computer or the processor executes the method according to the first aspect.

[0051] The present invention aims at the phenomenon of fuselage vibration and array element failure, and determines the array element , , The deviation of the axis direction from the ideal position , , , and determine the number of array elements that are working properly ; Secondly, in each pulse repetition period, the coordinates of the array elements and the phase center of the subarray for normal operation are calculated respectively, and on this basis, the array and subarray gains are calculated. , ; Again, according to the refined clutter model, calculate the clutter of the information point in each pulse repetition period, and finally calculate the clutter of each range ring , completed the clutter simulation of UAV-borne radar, and improved the authenticity of clutter simulation. It enables the simulation of airborne radar clutter to be realized even when the working environment of the carrier aircraft is harsh. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0053] Figure 1 It is a flow chart of a method for fine clutter simulation of airborne radar under the condition of fuselage jitter and array element failure provided by an embodiment of the present invention;

[0054] Figure 2 It is a flow chart of a method for fine clutter simulation of airborne radar under the condition of fuselage jitter and array element failure provided by an embodiment of the present invention;

[0055] Figure 3 It is a schematic diagram of a method for fine clutter simulation of airborne radar under the conditions of fuselage jitter and array element failure provided by an embodiment of the present invention;

[0056] Figure 4 It is a schematic diagram of a method for fine clutter simulation of airborne radar under the conditions of fuselage jitter and array element failure provided by an embodiment of the present invention;

[0057] Figure 5 It is a schematic diagram of the architecture of an airborne radar refined clutter simulation device under the conditions of fuselage jitter and array element failure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0059] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as open inclusion, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "examples", "specific examples" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner, that is, although they may be carried in the embodiments or examples of the above terms due to reasons such as the order and position of appearance, it is not limited to that they can be carried in combination by one embodiment or example.

[0060] In the description of the present invention, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, the meaning of "multiple" is two or more. In addition, for example, the same type of nouns may be described as two independent individuals by adding "A" and "B" at the end. In this case, the corresponding features defined as "A" and "B" are only used to distinguish the same type of individuals for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features.

[0061] In the description of the present invention, the expression "A and / or B" (where A and B are used to formally represent specific characteristic contents) is involved, and the corresponding expressions include the following three combinations: only A, only B, and a combination of A and B.

[0062] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0063] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0064] Embodiment 1:

[0065] Embodiment 1 of the present invention provides a method for simulating refined clutter of an airborne radar under the conditions of airframe vibration and array element failure, such as Figure 1As shown, including:

[0066] In step 201, according to the sub-array division model, the array is divided into N sub-arrays, a coherent processing interval (CPI) has a total of K pulses, the ideal position coordinates of the array element are given by , , The three components represent the ideal position of the array element, the vibration of the fuselage causing the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray .

[0067] In step 202, according to the array model, k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , calculate the array gain within the kth pulse repetition period and subarray gain , .

[0068] In step 203, the ground is divided into N r The distance ring, l The range rings are divided into N l information points, according to the refined clutter model, k Array gain within a pulse repetition period and subarray gain , calculate each information point in the k The echo signal vector within the pulse repetition period ,in For thei The azimuth angle between the information point and the array, i =1,2,...,N l , For the l The pitch angle of the range ring and the array, l =1,2,..., N r .

[0069] In step 204, according to each information point in k The echo signal vector within the pulse repetition period , calculate each information point K The echo signal vector of the pulse .

[0070] In step 205, each information point is used K The echo signal vector of the pulse , calculate the l The echo signal vector of the range ring .

[0071] The airborne radar transmitting antenna consists of M rows and N columns, with a total of M q array elements; among them, the sub-arrays are synthesized by column. After the fuselage shakes and array element failures occur, the number of array elements that work normally is , No. k The first pulse repetition period m The coordinates of the array element are d mk , the antenna array is divided into N Subarray, p The number of array elements in a normal working subarray is , No. k The first pulse repetition period p The phase center of the subarray is d spk , the number of distance fuzzy times is T, and the number of distance rings within the maximum unfuzzy distance is I , No. l The number of information points divided by the distance ring is N l , the number of pulses for coherent processing is K.

[0072] This embodiment provides a method for fine clutter modeling of UAV-borne radar under the condition of fuselage jitter and array element failure. First, according to the phenomenon of fuselage jitter and array element failure, the array element is determined. , , The deviation of the axis direction from the ideal position , , , and determine the number of array elements that are working properly ; Secondly, in each pulse repetition period, the coordinates of the array elements and the phase center of the subarray for normal operation are calculated respectively, and on this basis, the array and subarray gains are calculated. , ; Again, according to the refined clutter model, calculate the clutter of the information point in each pulse repetition period, and finally calculate the clutter of each range ring , completed the clutter simulation of UAV-borne radar, and improved the authenticity of clutter simulation. It enables the simulation of airborne radar clutter to be realized even when the working environment of the carrier aircraft is harsh, providing a basis for clutter suppression.

[0073] In actual use, according to the ideal position of the array element, the vibration of the fuselage causes the array element to be The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray Before, if Figure 2 As shown, the method also includes:

[0074] In step 200, in view of the body shaking phenomenon, it is determined that the body shaking causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position ; In view of the failure of array elements, determine the number of array elements that are working normally .

[0075] The above-mentioned object is to determine the phenomenon of body shaking, which causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position , specifically including:

[0076] The vibration of the fuselage causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position Satisfy the first relation.

[0077] The first relationship is .

[0078] in represents uniform distribution, , , is the jitter amplitude, is the angular frequency of the jitter, represents the speed of plane simple harmonic wave propagating along the plane, is the initial phase, Indicates time, Indicates that the array element is Coordinates on the axis.

[0079] The method of determining the number of array elements that are normally working according to the array element failure phenomenon is as follows: , specifically including:

[0080] When array element failure occurs and the quality of each array element is equal, the working state of a single array element obeys the binomial distribution, which is expressed as .

[0081] in Indicates The working status of each array element. A value of 0 indicates that the array element is normal, and a value of 1 indicates that the array element fails. represents the probability of array element failure, represents the binomial distribution.

[0082] Then the number of array elements that work normally when the array element fails is .

[0083] In actual application scenarios, the ideal position of the array element and the vibration of the fuselage cause the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine thek The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , specifically including:

[0084] Confirm k The first pulse repetition period during normal operation m Array element position coordinates .

[0085] No. k The first pulse repetition period during normal operation p The phase center of the subarray .

[0086] in, For the k The first pulse repetition period during normal operation m The array element The deviation of the axis direction from the ideal position, For the k The first pulse repetition period during normal operation m The array element The deviation of the axis direction from the ideal position, For the k The first pulse repetition period during normal operation m The array element The deviation of the axis direction from the ideal position, When there is no camera shake k The first pulse repetition period during normal operation m The array element The ideal position in the axial direction, When there is no camera shake k The first pulse repetition period during normal operation m The array element The ideal position in the axial direction, When there is no camera shake k The first pulse repetition period during normal operation m The array element The ideal position in the axial direction, For the k The first pulse repetition period during normal operation m The position coordinates of the array elements, For the k The first pulse repetition period p The phase center of each subarray, For the p The number of array elements that are working normally in a sub-array.

[0087] In some embodiments, according to the array model, k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , calculate the array gain within the kth pulse repetition period and subarray gain , specifically including:

[0088] Calculate the array gain within the kth pulse repetition period .

[0089] Calculate the kth pulse repetition period p Subarray Gain .

[0090] in, represents the array element gain, represents the maximum antenna gain of the array, Representative p The maximum antenna gain of the subarray is is the direction vector of the information point, is the array beam pointing direction vector, is the amplitude pattern of a single array element, is the working wavelength.

[0091] In an optional implementation, the method according to the refined clutter model, k Array gain within a pulse repetition period and subarray gain , calculate each information point in the k The echo signal vector within the pulse repetition period , specifically including:

[0092] Calculated in the k The echo signal vector within the pulse repetition period .

[0093] in, represents the random fluctuations introduced by clutter block reflections; Indicates the statistical distribution characteristics of clutter amplitude; represents the normalized noise power; Indicates the peak transmit power of the airborne radar; Indicates the kth pulse repetition period l The distance ring i Array gain in the direction of each information point; Indicates the operating wavelength; Represents the radar cross section (RCS) of the clutter block; Indicates pulse pressure benefit; Indicates l The distance ring i The distance between each information point and the array; is the Boltzmann constant; is the Kelvin temperature; is the receiver bandwidth; is the receiver noise factor; For system loss.

[0094] For the k The first pulse repetition period l The distance ring i The vector formed by the receiving antenna gain of each subarray in the direction of the information point is expressed as ; is the spatial steering vector within the kth pulse repetition period, expressed as .

[0095] in For the l The distance ring i The direction vector of each information point.

[0096] In a specific application scenario, the echo signal vector of each information point in the kth pulse repetition period , calculate the echo signal vector of K pulses at each information point , specifically including:

[0097] Calculate the first l The distance ring i Information points K The echo signal vector of the pulse .

[0098] in is the flight velocity vector of the carrier aircraft, For the l The distance ring i The direction vector of each information point.

[0099] The use of each information point K The echo signal vector of the pulse , calculate the l The echo signal vector of the range ring , specifically including:

[0100] Calculate the first lThe echo signal vector of the range ring .

[0101] in T is the number of distance blurs, For the The number of information points divided in the distance ring, For the The distance ring i Information points K The echo signal vector of the pulse, is the number of range rings within the maximum unambiguous distance.

[0102] This embodiment provides a method for fine clutter modeling of UAV-borne radar under the condition of fuselage jitter and array element failure. First, according to the phenomenon of fuselage jitter and array element failure, the array element is determined. , , The deviation of the axis direction from the ideal position , , , and determine the number of array elements that are working properly ; Secondly, in each pulse repetition period, the coordinates of the array elements and the phase center of the subarray for normal operation are calculated respectively, and on this basis, the array and subarray gains are calculated. , ; Again, according to the refined clutter model, calculate the clutter of the information point in each pulse repetition period, and finally calculate the clutter of each range ring , completed the UAV-borne radar clutter simulation and improved the authenticity of the clutter simulation.

[0103] This embodiment takes into account the changes in airborne radar index parameters between different pulse repetition periods, resulting in changes in airborne radar performance parameters that can be well reflected in changes in clutter amplitude, causing clutter distribution to change over time, and improving the non-stationarity of clutter distribution. When the carrier aircraft has a harsh working environment and a long working life, the higher the improvement in fuselage jitter amplitude and array element failure rate, the greater the difference in clutter distribution within different pulse repetition periods, and therefore, it is suitable for airborne radar clutter simulation in extreme environments.

[0104] Embodiment 2:

[0105] The present invention is based on the method described in Example 1, combined with specific application scenarios, and uses technical descriptions in related scenarios to illustrate the implementation process of the present invention in characteristic scenarios.

[0106] In this embodiment, the airborne radar transmitting antenna includes M OK, N Column, total M qarray elements, where the sub-arrays are synthesized in columns. For example, when the fuselage shakes and the array elements fail, the number of array elements that work normally is , No. k The first pulse repetition period m The coordinates of the array element are d mk , the antenna array is divided into N Subarray, p The number of array elements in a normal working subarray is , No. k The first pulse repetition period p The phase center of the subarray is d spk , the number of distance fuzzy times is T, and the number of distance rings within the maximum unfuzzy distance is I , No. l The number of information points divided by the distance ring is N l , the number of pulses for coherent processing is K.

[0107] The present invention provides a method for fine clutter modeling of unmanned aerial vehicle radar under the conditions of fuselage vibration and array element failure, such as Figure 3 and Figure 4 As shown, the following steps are included:

[0108] Step 1: The coordinate offset calculation unit of the array element causes the body to shake and the array element to , , The deviation of the axis direction from the ideal position , , Satisfy the following formula:

[0109] (1)

[0110] in represents uniform distribution, , , is the jitter amplitude, is the angular frequency of the jitter, represents the speed of plane simple harmonic wave propagating along the plane, is the initial phase, Indicates time, Indicates that the array element is Coordinates on the axis.

[0111] Step 2: In the normal working array element quantity estimation unit, when the quality of each array element is equal, the working state of a single array element obeys the binomial distribution, which is expressed as:

[0112] (2)

[0113] in Indicates The working status of each array element, '0' means the array element is normal, '1' means the array element is invalid. represents the probability of array element failure, represents binomial distribution. Then the expectation of the number of normal working array elements is:

[0114] (3)

[0115] Step 3: The array element position coordinates and subarray phase center calculation unit uses the models of steps 1 and 2 to determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , the expressions are:

[0116] (4)

[0117] (5)

[0118] Step 4: The array and subarray gain calculation units calculate the k The array and the first p Subarray Gain , , the expressions are:

[0119] (6)

[0120] (7)

[0121] in, represents the array element gain, represents the maximum antenna gain of the array, Representative p The maximum antenna gain of the subarray is is the direction vector of the information point, is the array beam pointing direction vector, is the amplitude pattern of a single array element, is the working wavelength.

[0122] Step 5: The single pulse echo signal vector calculation unit calculates each information point in the first k The echo signal vector within the pulse repetition period , the expression is:

[0123] (8)

[0124] in, represents the random fluctuations introduced by clutter block reflections; Indicates the statistical distribution characteristics of clutter amplitude; represents the normalized noise power; Indicates the peak transmit power of the airborne radar; Indicates the kth pulse repetition period l The distance ring i Array gain in the direction of each information point; Indicates the operating wavelength; Represents the radar cross-section of the clutter block; Indicates pulse pressure benefit; Indicates l The distance ring i The distance between each information point and the array; is the Boltzmann constant; is the Kelvin temperature; is the receiver bandwidth; is the receiver noise factor; For system loss.

[0125] For the k The first pulse repetition period l The distance ring i The vector formed by the receiving antenna gain of each subarray in the direction of the information point is expressed as:

[0126] (9)

[0127] is the kth pulse repetition period l The distance ring i The spatial steering vector in the direction of the information point is expressed as:

[0128] (10)

[0129] in is the direction vector of the i-th information point in the l-th distance ring.

[0130] Step 6: The multi-pulse echo signal vector calculation unit uses the result of step 5 to calculate each information point K The echo of a pulse , the expression is:

[0131] (11)

[0132] in is the flight velocity vector of the carrier aircraft, is the direction vector of the i-th information point in the l-th distance ring.

[0133] Step 7: The range ring clutter calculation unit uses the echo of each information point to calculate the echo signal vector of the range ring , the expression is:

[0134] (12)

[0135] Where T is the number of distance blurs, For the The number of information points divided in the distance ring, For the The echo signal vector of the K pulses of the ith information point in the range ring, is the number of range rings within the maximum unambiguous distance.

[0136] Embodiment 3:

[0137] like Figure 5 , is a schematic diagram of the architecture of an airborne radar fine clutter simulation device under the condition of fuselage jitter and array element failure according to an embodiment of the present invention. The airborne radar fine clutter simulation device under the condition of fuselage jitter and array element failure according to this embodiment includes one or more processors 21 and a memory 22. Figure 5 A processor 21 is taken as an example.

[0138] The processor 21 and the memory 22 may be connected via a bus or other means. Figure 5 The example of connecting through bus is taken in the following.

[0139] The memory 22, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs and non-volatile computer executable programs, such as the refined clutter simulation method for airborne radar under the conditions of fuselage jitter and array element failure in Example 1. The processor 21 executes the refined clutter simulation method for airborne radar under the conditions of fuselage jitter and array element failure by running the non-volatile software programs and instructions stored in the memory 22.

[0140] The memory 22 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage devices. In some embodiments, the memory 22 may optionally include a memory remotely arranged relative to the processor 21, and these remote memories may be connected to the processor 21 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0141] The program instructions / modules are stored in the memory 22, and when executed by the one or more processors 21, the method for fine-grained clutter simulation of airborne radar under the conditions of fuselage jitter and array element failure in the above-mentioned embodiment 1 is executed.

[0142] It is worth noting that the information interaction, execution process, etc. between the modules and units within the above-mentioned devices and systems are based on the same concept as the processing method embodiment of the present invention. The specific contents can be found in the description of the method embodiment of the present invention and will not be repeated here.

[0143] A person skilled in the art may understand that all or part of the steps in the various methods of the embodiments may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the storage medium may include: a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, etc.

[0144] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure, characterized in that: include: According to the subarray partitioning model, the array is divided into N subarrays, there are a total of K pulses, the ideal position coordinates of the array element are given by , , Three components represent; According to the ideal position of the array element, the vibration of the fuselage causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray ; According to the array model, k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , calculate the k Array gain within a pulse repetition period and subarray gain , ; With the fuselage as the center, the ground is divided N r distance ring, l The range rings are divided into N l information points, according to the refined clutter model, k Array gain within a pulse repetition period and subarray gain , calculate each information point in the k The echo signal vector within the pulse repetition period ,in For the i The azimuth angle between the information point and the array, i =1,2,...,N l , For the l The range rings and the elevation angle of the array, l =1,2,..., N r ; According to each information point in k The echo signal vector within the pulse repetition period , calculate each information point K The echo signal vector of the pulse ; Take advantage of every information point K The echo signal vector of the pulse , calculate the l The echo signal vector of the range ring .

2. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1 is characterized in that: The ideal position of the array element and the vibration of the fuselage cause the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , specifically including: Confirm k The first pulse repetition period during normal operation m Array element position coordinates ; No. k The first pulse repetition period during normal operation p The phase center of the subarray ; in, For the k The first pulse repetition period during normal operation m The array element The deviation of the axis direction from the ideal position, For the k The first pulse repetition period during normal operation m The array element The deviation of the axis direction from the ideal position, For the k The first pulse repetition period during normal operation m The array element The deviation of the axis direction from the ideal position, When there is no camera shake k The first pulse repetition period during normal operation m The array element The ideal position in the axial direction, When there is no camera shake k The first pulse repetition period during normal operation m The array element The ideal position in the axial direction, When there is no camera shake k The first pulse repetition period during normal operation m The array element The ideal position in the axial direction, For the k The first pulse repetition period during normal operation m The position coordinates of the array elements, For the k The first pulse repetition period p The phase center of each subarray, For the p The number of array elements that are working normally in a sub-array.

3. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1 is characterized in that: According to the array model, k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray , calculate the array gain within the kth pulse repetition period and subarray gain , specifically including: Calculate the array gain within the kth pulse repetition period ; Calculate the kth pulse repetition period p Subarray Gain ; in, represents the array element gain, represents the maximum antenna gain of the array, Representative p The maximum antenna gain of the subarray is is the direction vector of the information point, is the array beam pointing direction vector, is the amplitude pattern of a single array element, is the working wavelength.

4. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1, characterized in that: According to the refined clutter model, k Array gain within a pulse repetition period and subarray gain , calculate each information point in the k The echo signal vector within the pulse repetition period , specifically including: Calculated in the k The echo signal vector within the pulse repetition period ; in, represents the random fluctuations introduced by clutter block reflections; Indicates the statistical distribution characteristics of clutter amplitude; represents the normalized noise power; Indicates the peak transmit power of the airborne radar; Indicates the kth pulse repetition period l The distance ring i Array gain in the direction of each information point; Indicates the operating wavelength; Represents the radar cross-section of the clutter block; Indicates pulse pressure benefit; Indicates l The distance ring i The distance between each information point and the array; is the Boltzmann constant; is the Kelvin temperature; is the receiver bandwidth; is the receiver noise factor; is the system loss; For the k The first pulse repetition period l The distance ring i The vector formed by the receiving antenna gain of each subarray in the direction of the information point is expressed as ; is the kth pulse repetition period l The distance ring i The spatial guidance vector in the direction of the information point is expressed as ; in For the l The distance ring i The direction vector of each information point.

5. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1, characterized in that: The echo signal vector of each information point in the kth pulse repetition period is , calculate each information point K The echo signal vector of the pulse , specifically including: Calculate the first l The distance ring i Information points K The echo signal vector of the pulse ; in is the flight velocity vector of the carrier aircraft, For the l The distance ring i The direction vector of each information point.

6. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1 is characterized in that: The use of each information point K The echo signal vector of the pulse , calculate the l The echo signal vector of the range ring , specifically including: Calculate the first l The echo signal vector of the range ring ; in T is the number of distance blurs, For the The number of information points divided in the distance ring, For the The distance ring i Information points K The echo signal vector of the pulse, is the number of range rings within the maximum unambiguous distance.

7. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1, characterized in that: In the above, according to the ideal position of the array element, the vibration of the fuselage causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position and the number of array elements that are working properly in the event of an array element failure and p The number of array elements in a subarray that works normally , determine the k The first pulse repetition period during normal operation m Array element position coordinates and p The phase center of the subarray Previously, methods also included: Regarding the body shaking phenomenon, determine the body shaking that causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position ; In view of the failure of array elements, determine the number of array elements that are working normally .

8. The method for fine-grained clutter simulation of airborne radar under the conditions of fuselage vibration and array element failure according to claim 7 is characterized in that: The above-mentioned object is to determine the phenomenon of body shaking, which causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position , specifically including: The vibration of the fuselage causes the array element to The deviation of the direction from the ideal position , array element in The deviation of the direction from the ideal position And the array element The deviation of the direction from the ideal position Satisfy the first relationship; The first relationship is ; in represents uniform distribution, , , is the jitter amplitude, is the angular frequency of the jitter, represents the speed of plane simple harmonic wave propagating along the plane, is the initial phase, Indicates time, Indicates that the array element is The coordinates of the ideal position on the axis.

9. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 7, characterized in that: The method of determining the number of array elements that are normally working according to the array element failure phenomenon is as follows: , specifically including: When array element failure occurs and the quality of each array element is equal, the working state of a single array element obeys the binomial distribution, which is expressed as ; in Indicates The working status of each array element. A value of 0 indicates that the array element is normal, and a value of 1 indicates that the array element is invalid. represents the probability of array element failure, represents binomial distribution; Then the number of array elements that work normally when the array element fails is .

10. The method for simulating refined clutter of airborne radar under the conditions of fuselage vibration and array element failure according to claim 1, characterized in that: The airborne radar transmitting antenna consists of M rows and N columns, a total of M q array element; The subarrays are synthesized by column. After the fuselage shakes and array element failures occur, the number of array elements that work normally is , No. k The first pulse repetition period m The coordinates of the array element are d mk , the antenna array is divided into N Subarray, p The number of array elements in a normal working subarray is , No. k The first pulse repetition period p The phase center of the subarray is d spk , the number of distance fuzzy times is T, and the number of distance rings within the maximum unfuzzy distance is I , No. l The number of information points divided by the distance ring is N l , the number of pulses for coherent processing is K.

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