A method to improve radar lateral resolution by imitating the working principle of retinal ganglion cells

Abstract

The present invention provides a method for improving the lateral resolution of a radar by simulating the working principle of retinal ganglion cells. The method specifically includes the following steps: step S1, the radar performs a rough scan until a suspicious target is found, and determines the center position of the suspicious target based on the echo generated after contacting the suspicious target; step S2, sets the scanning range of the radar based on the center of the suspicious target; step S3, transmits a predetermined waveform that the radar is ready to transmit based on the scanning range; step S4, based on the predetermined waveform, causes the radar to scan in a predetermined scanning mode and receive the echo corresponding to each scan, and organizes the echoes into an echo sequence; step S5, performs a second-order difference on the echo sequence to obtain an echo of a predetermined resolution; step S6, determines the number of suspicious targets based on the echo of the predetermined resolution; wherein the echo is expressed in the form of echo energy, the point with prominent echo energy is the contour point of the suspicious target, and the center of the contour point is the center of the suspicious target.

Description

Technical Field

[0001] The present invention belongs to the field of radar detection and relates to a method for improving the lateral resolution of radar by simulating the working principle of retinal ganglion cells. Background Art

[0002] Traditional radar detection involves transmitting electromagnetic waves through a radar antenna. These waves are then reflected by the target and received by the receiver. However, this type of radar detection method has low lateral resolution. When detecting multiple suspicious targets within a single beamwidth, it can only detect the presence of a suspicious target, but cannot distinguish their number or shape.

[0003] like Figure 1 As shown in the figure, the energy of the emitted electromagnetic wave reaches its peak in the direction of maximum radiation and gradually decays to both sides. The beam width of the radar is θ w This refers to the angle between the two directions on either side of the maximum radiation direction where the radiation power drops by 3dB. It is generally believed that beyond this beamwidth, the power decays rapidly and the echo cannot be received.

[0004] like Figure 2 As shown in Figure 2, the radar lateral resolution ρ refers to the minimum lateral distance between two targets that can be distinguished. In traditional radar detection, when two targets are within a beam width ( Figure 1 For targets 1 and 2, the echo appears as a single point and is indistinguishable. Assuming the distance between the two targets and the radar is R, the lateral resolution of the target at distance R is approximately arc length ρ = R * θ. For example, for a traditional radar antenna, its 3dB beamwidth is approximately 0.01 rad. Its lateral resolution at 1 kilometer is calculated according to the formula ρ = R * θ: 1000 meters * (0.01 rad / pi * 180) ≈ 573 meters. This means that for two flying targets at 1 kilometer, when the lateral distance between the targets is less than 573 meters, their echoes will appear as the same energy point and will be indistinguishable. Summary of the Invention

[0005] To solve the above problem, a method for distinguishing the number of targets within a radar beam width is provided. The present invention adopts the following technical solution:

[0006] The present invention provides a method for improving the lateral resolution of a radar by simulating the working principle of retinal ganglion cells, which is characterized in that the method specifically includes the following steps: step S1, the radar performs a rough scan until a suspicious target is found, and determines the center position of the suspicious target based on the echo generated after contacting the suspicious target; step S2, sets the scanning range of the radar based on the center of the suspicious target; step S3, transmits a predetermined waveform that the radar is ready to transmit based on the scanning range; step S4, based on the predetermined waveform, causes the radar to scan in a predetermined scanning mode and receives the echo corresponding to each scan, and organizes the echoes into an echo sequence; step S5, performs a second-order difference on the echo sequence to obtain an echo of a predetermined resolution; step S6, determines the number of suspicious targets based on the echo of the predetermined resolution; wherein the echo is expressed in the form of echo energy, and the suspicious target is determined based on the corresponding echo energy highlight point.

[0007] According to the method provided by the present invention for improving the lateral resolution of a radar by simulating the working principle of retinal ganglion cells, the method may also have the following technical features: assuming that the center of a suspicious target obtained by a rough radar scan is C, the fine scanning range is the range illuminated by the radar single beam width:

[0008] (C-θ w / 2,C+θ w / 2)

[0009] Where θ w is the beam width of the radar, and C is the center position of the radar when a rough scan is performed to obtain a suspicious target, also recorded as the beam center.

[0010] According to the present invention, a method for improving the lateral resolution of a radar by simulating the working principle of retinal ganglion cells may also have the following technical features: the predetermined waveform is obtained by a predetermined modulation method based on a Gaussian distribution formula. The predetermined modulation method is specifically: by continuously adjusting the angular difference between the radar and the beam center during transmission, the echo energy received after the radar transmits the signal satisfies the following expression:

[0011]

[0012] Where θ is the angle between any point within the radar beam width and the beam center, and θ0 is the angle between the beam edge and the beam center. When the radar scans according to the predetermined modulation method, the total echo energy during one radar scan is:

[0013]

[0014] Where x i For the i A specific signal at i )·G(θ i ) is thei A specific signal x at i Echo energy.

[0015] According to a method for improving the lateral resolution of a radar by simulating the working principle of retinal ganglion cells provided by the present invention, it can also have the following technical features: the predetermined scanning mode is that the radar performs fine scanning at a predetermined angle step S over time, the predetermined angle step S is an initial setting value, and each time the radar rotates and scans according to the predetermined angle step S, it conforms to the predetermined waveform, that is, it satisfies the Gaussian weight distribution. The predetermined scanning mode is specifically as follows: when the radar scans for the first time, the radar rotation angle step is S, and the angle rotated by the radar from the starting position of the scan is recorded as S1, G(θ2) to G(θ k+1 ) to meet the predetermined waveform again, and obtain the echo energy Z when the radar rotates S1 for the first scan k+1 , the expression is as follows:

[0016]

[0017] When the radar scans for the second time, the radar rotation angle step is S, and the angle the radar has rotated from the starting position of the scan is recorded as S2, G(θ3) to G(θ k+2 ) to meet the predetermined waveform again, and obtain the echo energy Z when the radar rotates S2 for the second scan k+2 , the expression is as follows:

[0018]

[0019] According to the method provided by the present invention, a method for improving the lateral resolution of radar by imitating the working principle of retinal ganglion cells can also have the following technical features, wherein the echo sequence is composed of the Z corresponding to the step size S after rotating n times k+n The second-order difference is defined as:

[0020] Z=(Z k+2 -Z k+1 )-(Z k+1 -Z k ),

[0021] For echo sequence Z k Take the second-order difference:

[0022] Z=[E(x)*G(θ)]”

[0023] Get the echo with the predetermined resolution.

[0024] The present invention provides a method for improving the lateral resolution of a radar by simulating the working principle of retinal ganglion cells, which is characterized in that the method specifically includes the following steps: step S1, the radar performs a rough scan until a suspicious target is found, and determines the suspicious target based on the echo generated after contacting the suspicious target; step S2, the scanning range of the radar is set based on the position of the suspicious target; step S3, the predetermined waveform to be transmitted by the radar is modulated based on the scanning range; step S4, based on the predetermined waveform, the radar is scanned in a predetermined scanning mode over time to obtain and receive echoes of a predetermined resolution; step S5, the number and shape of the suspicious targets are determined based on the echoes of the predetermined resolution; wherein the echo is expressed in the form of echo energy, the suspicious target is determined based on the corresponding echo energy highlight point, the predetermined waveform is a Gaussian second-order difference waveform, and the predetermined scanning mode is that the radar performs fine scanning at a predetermined angle step size S over time.

[0025] Functions and effects of the invention

[0026] The method for improving radar lateral resolution based on the operating principle of retinal ganglion cells, as described in the present invention, first performs a coarse scan to determine the center position of the radar when it detects a suspicious target. Then, based on the operating principle of retinal ganglion cells, the scanning range is determined based on the center position of the suspicious target. A waveform with a Gaussian weight distribution is emitted, and a fine scan is performed with a small predetermined angular step size. Finally, the echoes generated by the waveform are subjected to a second-order difference to obtain high-resolution echoes, thereby determining the shape and number of suspicious targets. This method not only improves the radar's lateral resolution but also solves the problem of the radar being unable to distinguish multiple suspicious targets within a single beamwidth.

[0027] The method of improving the lateral resolution of radar by imitating the working principle of retinal ganglion cells of the present invention first uses coarse scanning to determine suspicious targets, thereby improving the timeliness of resolving the number of suspicious targets. At the same time, when fine scanning is performed with a small predetermined angle step, the ratio S / θ of the step length S to the beam width θ is proportional to the improvement in resolution. As long as the angle between multiple targets and the radar is less than the minimum predetermined angle step S for fine scanning of the radar, the separation of suspicious targets can be achieved. Moreover, the smaller the predetermined angle step for fine scanning and the more scans are performed, the greater the improvement in resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the radar beam width;

[0029] Figure 2 It is a schematic diagram of the radar's lateral resolution;

[0030] Figure 3 This is a flow chart of a method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells in an embodiment of the present invention;

[0031] Figure 4 This is a schematic diagram of the modeling of the dendritic weight distribution of the receptive field of retinal ganglion cells;

[0032] Figure 5 This is a diagram of the working principle of retinal ganglion cells;

[0033] Figure 6 This is a schematic diagram of distinguishing two targets that are close to each other using the Gaussian second-order derivative operator;

[0034] Figure 7 It is a schematic diagram of distinguishing targets at close distances and resolving shapes through a two-dimensional Gaussian second-order derivative detection operator;

[0035] Figure 8 is a schematic diagram of a radar transmitting a predetermined waveform in an embodiment of the present invention;

[0036] Figure 9 1 is a comparison chart of experimental results of two embodiments of the present invention;

[0037] Figure 10 This is a flow chart of a method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells according to embodiment 2 of the present invention. DETAILED DESCRIPTION

[0038] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the following is a detailed description of the method of improving the lateral resolution of radar by imitating the working principle of retinal ganglion cells in the present invention in combination with embodiments and drawings.

[0039] <Example 1>

[0040] Figure 3 This is a flow chart of a method for improving the lateral resolution of radar by simulating the working principle of retinal ganglion cells in this embodiment.

[0041] like Figure 3 As shown, the method for improving the lateral resolution of radar by imitating the working principle of retinal ganglion cells includes the following steps:

[0042] In step S1, the radar performs a rough scan until a suspicious target is found, and determines the suspicious target based on the echo generated after contact with the suspicious target.

[0043] In this embodiment, the echo is expressed in the form of echo energy, and the suspicious target is determined based on the corresponding echo energy prominent point.

[0044] Step S2: Setting the scanning range of the radar based on the location of the suspicious target.

[0045] In this embodiment, the scanning range is the range illuminated by the radar single beam width:

[0046] (C-θ w / 2,C+θ w / 2)

[0047] Where θ w is the beam width of the radar, and C is the center position of the radar when a rough scan is performed to obtain a suspicious target, also recorded as the beam center.

[0048] Step S3: transmitting a predetermined waveform for the radar to transmit based on the scanning range.

[0049] In this embodiment, the predetermined waveform is obtained by simulating the working principle of retinal ganglion cells, and the working principle is specifically as follows:

[0050] Retinal ganglion cells receive light energy stimulation through their dendrites and aggregate the energy to the cell body to output action potentials of different frequencies. The range of the dendrites of retinal ganglion cells is called the retinal ganglion cell receptive field, that is, the range that can receive light. The receptive field of retinal ganglion cells is center-surround and exhibits antagonistic characteristics. Specifically:

[0051] There are two main types of ganglion cells in the retina: ON type and OFF type. These two types of retinal ganglion cells work as follows:

[0052] When light is applied to the middle area of ​​the receptive field of retinal ganglion cells and light is removed from the peripheral area, the output potential frequency of ON-type cells reaches the highest frequency;

[0053] When the light is removed from the middle area of ​​the receptive field of the retinal ganglion cell and the light is restored in the peripheral area, the output potential frequency of the OFF-type cell reaches the highest frequency.

[0054] Figure 4 It is a model of the dendritic weight distribution of the receptive field of retinal ganglion cells.

[0055] Measurements have shown that the dendritic weight distribution within the receptive field of retinal ganglion cells can be mathematically modeled as the second-order derivative of a two-dimensional Gaussian distribution with the center of the receptive field as the origin, which acts as a differential processing of light between the central and peripheral areas. Specifically:

[0056] First, take the second-order derivative of a one-dimensional Gaussian distribution as an example:

[0057]

[0058] Where σ is the standard deviation of the Gaussian distribution, x is the horizontal coordinate, and G"(x;σ) is the function value.

[0059] Figure 5 This is a diagram of the working principle of retinal ganglion cells.

[0060] like Figure 5 As shown, when the target 10 is imaged on the retina 12 through the lens 11, the retinal cells simultaneously receive multiple signal intensities E(x i ), for any point x i , the receptive field weight of the retinal ganglion cell is G"(x;σ), and the dendritic output value of the retinal ganglion cell is E(x i )·G”(x i ), the total output of the retinal ganglion cells is:

[0061]

[0062] Then, accompanied by slight shaking of the eyes, the retinal ganglion cells continuously scan and receive external light stimuli to detect the target, and this process is similar to the process of convolving the light signal using the Gaussian second-order derivative operator. Specifically:

[0063] Figure 6 This is a schematic diagram of distinguishing two targets that are close to each other using the Gaussian second-order derivative operator.

[0064] Figure 7 This is a schematic diagram of using a two-dimensional Gaussian second-order derivative detection operator to distinguish targets at close distances and resolve shapes.

[0065] like Figure 6 As shown in the figure, when the Gaussian second-order derivative detection operator is first used, the Gaussian second-order derivative operator moves with a small step size S. In the process of convolving the signal, the energy of the central area and the surrounding area of ​​the receptive field is continuously differentiated. As long as the distance between the signals is greater than the step size S of the Gaussian second-order derivative operator, a strong reaction will be generated at the position where the signal changes, and the target can be distinguished based on this reaction.

[0066] The same effect can be achieved by using the two-dimensional Gaussian second-order derivative detection operator, such as Figure 7 As shown in the figure, a square target and a triangular target are 6 pixels apart. When the Gaussian second-order derivative detection operator with a size of 15*15 pixels is convolved, the convolution step size is 1. It can not only clearly distinguish the two targets, but also produce different pattern responses to the edges of the two targets with different shapes.

[0067] In summary, retinal ganglion cells can not only distinguish the number of targets, but also use different pattern responses to distinguish the shape of the targets.

[0068] Since the way radar detects targets is very similar to the working principle of retinal ganglion cells, it can be compared to the principle of radar receiving echoes. Therefore, the radar antenna is compared to the retinal ganglion cells, and the radar beam width is compared to the receptive field of the retinal ganglion cells.

[0069] The modulated signal emitted by the radar can be modulated through amplitude modulation, phase modulation, and frequency modulation.

[0070] In this embodiment, the radar is modulated by a frequency modulation method to obtain a sinusoidal wave signal with a specific waveform. That is, within one pulse period, the frequency of the signal changes with time, and its expression is:

[0071]

[0072] Where A is the pulse amplitude, K is the frequency modulation slope, and In this formula, B is the bandwidth of the signal and T is the time width or instant width.

[0073] When the distance needs to be resolved within a beam width θ w When different targets are detected, the predetermined waveform of the radar is Gaussian weighted distribution. The expression of the Gaussian weighted distribution is:

[0074]

[0075] Where σ is the standard deviation of the Gaussian distribution, x is the horizontal coordinate, and G(x;σ) is the function value.

[0076] In this embodiment, when the radar transmits a signal, a pulse phase modulation method is used. By continuously adjusting the angle difference between the radar and the beam center during transmission, the echo energy received after the radar transmits the signal satisfies the following expression:

[0077]

[0078] Where θ is the angle between any point within the radar beam width and the beam center, and θ0 is the angle between the beam edge and the beam center.

[0079] Figure 8 Schematic diagram of the radar transmitting a predetermined waveform in this embodiment.

[0080] like Figure 8 As shown in the figure, when the radar transmits a predetermined waveform according to a predetermined modulation method, the total echo energy during one scan is:

[0081]

[0082] Where x i For the i A specific signal at i )·G(θ i ) is its echo energy.

[0083] Step S4: Based on the predetermined waveform, the radar is made to scan in a predetermined scanning manner and receive echoes corresponding to each scan, and the echoes are combined into an echo sequence.

[0084] In this embodiment, the predetermined scanning mode is that the radar performs fine scanning at a predetermined angle step S over time. The predetermined angle step S is an initial setting value. Each time the radar rotates and scans according to the predetermined angle step S, it conforms to the predetermined waveform and satisfies the Gaussian weight distribution.

[0085] The above predetermined scanning method is specifically as follows:

[0086] When the radar scans for the first time, the radar rotation angle step is S, and the angle the radar has rotated from the starting position of the scan is recorded as S1, G(θ2) to G(θ k+1 ) to meet the predetermined waveform again, and obtain the echo energy Z when the radar rotates S1 for the first scan k+1 , the expression is as follows:

[0087]

[0088] When the radar scans for the second time, the radar rotation angle step is S, and the angle the radar has rotated from the starting position of the scan is recorded as S2, G(θ3) to G(θ k+2 ) to meet the predetermined waveform again, and obtain the echo energy Z when the radar rotates S2 for the second scan k+2 , the expression is as follows:

[0089]

[0090] In this embodiment, the echo sequence Z k The echo energy Z corresponding to the predetermined angle step S value is k+n composition.

[0091] Step S5: performing second-order difference on the echo sequence to obtain echoes of a predetermined resolution.

[0092] In this embodiment, the edge information of the echo energy change is retained by the second-order difference, and the second-order difference is defined as:

[0093] Z=(Z k+2 -Z k+1 )-(Z k+1 -Z k ),

[0094] For echo sequence Z k Make the second-order difference, that is:

[0095] Z=[E(x)*G(θ)]”.

[0096] Step S6: Determine the number and shape of suspicious targets based on the echo sequence of the second-order difference to obtain echoes of a predetermined resolution.

[0097] In this embodiment, the echo of predetermined resolution is obtained based on the echo sequence of second-order difference, and the prominent points of echo energy after the second-order difference are the edge information of the suspicious target, i.e., the contour points. Therefore, correspondingly, the echo sequence subjected to the second-order difference can reflect the number and shape of the suspicious targets.

[0098] In this embodiment, when the radar, simulating the operating principle of retinal ganglion cells, emits a waveform with a Gaussian weight distribution and continuously scans with a predetermined angular step size S, the ratio S / θ of the predetermined angular step size S to the beamwidth θ is directly proportional to the resolution improvement. The smaller the predetermined angular step size, the higher the resolution. Furthermore, the predetermined angular step size S can be adjusted based on the resolution of the suspicious target. As long as the angle between multiple targets and the radar is less than the minimum predetermined angular step size S for the radar's fine scanning, the targets can be separated.

[0099] <Example 2>

[0100] For ease of expression, the same symbols are given to the same steps in the second embodiment as in the first embodiment, and the same descriptions are omitted.

[0101] In this embodiment, the method of transmitting a Gaussian second-order derivative waveform is used instead of the method of transmitting a Gaussian waveform and then performing a second-order difference:

[0102] Specifically:

[0103] According to the property of convolution, the derivative after convolution is equivalent to the convolution of the derivative:

[0104]

[0105] So we get:

[0106] [E(x)*G(θ)]”=E(x)*G”(x).

[0107] Figure 9 1 is a comparison chart of experimental results of two embodiments of the present invention.

[0108] like Figure 9 As shown in the above formula, directly using the second-order derivative operator of Gaussian to convolve the signal is equivalent to convolving the Gaussian operator with the signal and then taking the second-order difference.

[0109] Figure 10 This is a flow chart of a method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells according to embodiment 2 of the present invention.

[0110] like Figure 10As shown, this embodiment provides a method for improving the lateral resolution of radar by simulating the working principle of retinal ganglion cells, and the following steps can also be used:

[0111] Step S1: The radar performs a rough scan until a suspicious target is found, and determines the suspicious target based on the echo generated after contact with the suspicious target;

[0112] Step S2, setting the radar scanning range based on the location of the suspicious target;

[0113] Step S3', modulating the radar's prepared transmission waveform into a Gaussian second-order difference waveform based on the scanning range;

[0114] Step S4', based on the Gaussian second-order difference waveform, the radar is made to perform fine scanning according to a predetermined angle step S over time to obtain and receive an echo of a predetermined resolution;

[0115] Step S5: determining the number and shape of suspicious targets based on the echoes of a predetermined resolution.

[0116] In this embodiment, the echo obtained by transmitting a Gaussian second-order difference waveform is equivalent to the echo subjected to second-order difference in Example 1. The prominent points in the echo energy of this embodiment are the edge information of the suspicious target, i.e., the contour points, and the echo of the predetermined resolution is obtained based on the transmitted Gaussian second-order difference waveform. Therefore, correspondingly, the predetermined resolution can reflect the number and shape of the suspicious targets.

[0117] Example Function and Effect

[0118] According to the method for improving the lateral resolution of a radar based on the working principle of simulated retinal ganglion cells provided in this embodiment, a rough scan is first performed to determine a suspicious target. Then, based on the working principle of simulated retinal ganglion cells, a waveform with a Gaussian weight distribution is emitted according to the center position of the suspicious target to perform a fine scan with a small predetermined angular step size. Finally, a second-order difference is performed on the echo obtained by emitting the waveform to obtain a high-resolution echo, thereby determining the number of suspicious targets, improving the lateral resolution of the radar, and solving the problem that the radar cannot distinguish multiple suspicious targets within a beam width.

[0119] In the embodiment, the radar uses a large-scale coarse scan to determine suspicious targets but cannot distinguish multiple suspicious targets within a beam width. Although a fine scan with a small predetermined angle step can distinguish the number of suspicious targets by improving the lateral resolution within a beam width, this scanning method needs to be performed multiple times and has low timeliness. Therefore, in this embodiment, a coarse scan is first used to determine the suspicious target, and then a fine scan is performed based on the center of the suspicious target. The combination of coarse scanning and fine scanning greatly improves the timeliness and accuracy of the radar in distinguishing the number of suspicious targets.

[0120] In one embodiment, when a radar emits a waveform with a Gaussian weight distribution, its detection principle is similar to that of retinal ganglion cells. When fine scanning is performed based on this waveform with a small predetermined angular step size, the ratio (S / θ) of the step size S to the beamwidth θ is proportional to the improvement in resolution. As long as the angle between multiple targets and the radar is less than the minimum predetermined angular step size S for fine scanning, the detection effect is equivalent to that of retinal ganglion cells. This greatly improves the accuracy and efficiency of resolving multiple targets within a radar beamwidth, thereby enabling the separation of suspicious targets. Furthermore, the smaller the predetermined angular step size for fine scanning and the greater the number of scans, the greater the improvement in resolution. For example, with a traditional radar scanning method, the 3dB beamwidth is approximately 0.01 rad, making targets within the beamwidth indistinguishable. However, setting S to 0.001 rad for scanning improves resolution tenfold.

[0121] According to the method provided in this embodiment, based on actual conditions and reasonable prior knowledge, as long as a reasonable predetermined angle step is set and the number of scans is balanced, not only the scanning resolution but also the scanning efficiency can be improved.

[0122] The above embodiments are only used to illustrate specific implementations of the present invention, and the present invention is not limited to the description scope of the above embodiments.

[0123] In the above embodiment, when transmitting a signal with Gaussian weight distribution, pulse width modulation, double pulse interval modulation and pulse code modulation methods may also be used.

Claims

1. A method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells, which is used to clearly distinguish and detect multiple small targets within a radar beam width, characterized by: The specific steps include: Step S1: The radar performs a rough scan until a suspicious target is found, and determines the suspicious target based on the echo generated after contact with the suspicious target; Step S2, setting the scanning range of the radar based on the position of the suspicious target; Step S3, obtaining a predetermined waveform for the radar to be transmitted based on the scanning range; Step S4, based on the predetermined waveform, the radar is caused to scan in a predetermined scanning manner and receive echoes corresponding to each scan, and the echoes are combined into an echo sequence; Step S5, performing second-order difference on the echo sequence to obtain echoes of a predetermined resolution; Step S6, determining the number of the suspicious targets based on the echoes of the predetermined resolution; The echo is expressed in the form of echo energy, and the suspicious target is determined based on the corresponding echo energy highlight point. The predetermined waveform is obtained by a predetermined modulation method based on a Gaussian distribution formula, and the predetermined modulation method is specifically: By continuously adjusting the angular difference between the radar and the beam center during transmission, the echo energy received after the radar transmits the signal satisfies the following expression: Where θ is the angle between any point within the radar beam width and the beam center, and θ0 is the angle between the beam edge and the beam center. When the radar scans according to the predetermined modulation method, the total echo energy of the radar during one scan is: Where x i For the i The specific signal at E(x i )·G(θ i ) is the i The echo energy of the specific signal at .

2. The method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells according to claim 1, characterized in that: in, The scanning range is the range illuminated by the radar single beam width: (C-θ w / 2,C+θ w / 2) Where θ w is the beam width of the radar, and C is the center position of the radar when a rough scan is performed to obtain a suspicious target, also recorded as the beam center.

3. The method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells according to claim 1, characterized in that: in, The predetermined scanning mode is that the radar performs fine scanning at a predetermined angle step S over time. The predetermined angle step S is an initial setting value. Each time the radar rotates and scans according to the predetermined angle step S, it conforms to the predetermined waveform, that is, it satisfies the Gaussian weight distribution. The predetermined scanning mode is specifically: When the radar scans for the first time, the radar rotation angle step is S, and the angle rotated by the radar from the starting position of the scan is recorded as S1, G(θ2) to G(θ k+1 ) re-satisfies the predetermined waveform, and obtains the echo energy Z when the radar rotates S1 for the first time of scanning k+1 , the expression is as follows: When the radar scans for the second time, the radar rotation angle step is S, and the angle rotated by the radar from the starting position of the scan is recorded as S2, G(θ3) to G(θ k+2 ) re-satisfies the predetermined waveform, and obtains the echo energy Z when the radar rotates S2 for the second time of scanning k+2 , the expression is as follows:

4. The method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells according to claim 3, characterized in that: in, The echo sequence consists of several Z corresponding to the predetermined angle step S value. k+n composition, The second-order difference is defined as: Z=(Z k+2 -WITH k+1 )-(WITH k+1 -WITH k ), For echo sequence Z k Perform the second-order difference: Z=[E(x) * G(θ)]”, An echo with the predetermined resolution is obtained.

5. A method for improving radar lateral resolution by simulating the working principle of retinal ganglion cells, which is used to clearly distinguish and detect multiple small targets within a radar beam width, characterized by: The specific steps include: Step S1: The radar performs a rough scan until a suspicious target is found, and determines the suspicious target based on the echo generated after contact with the suspicious target; Step S2, setting the scanning range of the radar based on the position of the suspicious target; Step S3', modulating a predetermined waveform to be transmitted by the radar based on the scanning range; Step S4', based on the predetermined waveform, causing the radar to scan in a predetermined scanning manner over time to obtain and receive echoes of a predetermined resolution; Step S5, determining the number and shape of the suspicious targets based on the echoes of the predetermined resolution; The echo is expressed in the form of echo energy, and the suspicious target is determined based on the corresponding echo energy highlight point. The predetermined waveform is a Gaussian second-order difference waveform, The predetermined scanning mode is that the radar performs fine scanning at a predetermined angle step S over time. The predetermined waveform is obtained by a predetermined modulation method based on a Gaussian distribution formula, and the predetermined modulation method is specifically: By continuously adjusting the angular difference between the radar and the beam center during transmission, the echo energy received after the radar transmits the signal satisfies the following expression: Where θ is the angle between any point within the radar beam width and the beam center, and θ0 is the angle between the beam edge and the beam center. When the radar scans according to the predetermined modulation method, the total echo energy of the radar during one scan is: Where x i For the i The specific signal at E(x i )·G(θ i ) is the i The echo energy of the specific signal at .

Images