Method for aligning any modal beam of vortex electromagnetic wave to same target

Abstract

The invention discloses a method for aligning any modal beam of vortex electromagnetic waves to the same target, and relates to the field of vortex electromagnetic wave radar high-resolution imaging and target recognition. Comprising the following steps: acquiring a target position in a phased array plane wave mode, and aligning a vortex electromagnetic wave beam axis with the target position; according to the divergence angle of the vortex electromagnetic wave in any mode, determining a target pointing coordinate of the vortex electromagnetic wave beam in the auxiliary coordinate system; according to the target position, converting a target pointing coordinate of the vortex electromagnetic wave beam under the auxiliary coordinate system to an antenna coordinate system; and calculating an off-axis angle and a rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinate of the vortex electromagnetic wave beam under the antenna coordinate system, and correcting the pointing of the vortex electromagnetic wave beam. The problem that beams cannot be aligned with the same target due to different modal divergence angles of vortex electromagnetic waves is solved.

Description

Technical Field

[0001] The present invention relates to the field of high-resolution imaging and target recognition of vortex electromagnetic wave radar, and in particular to a method for aiming vortex electromagnetic wave arbitrary mode beams at the same target. Background Art

[0002] Vortex electromagnetic waves, physically speaking, are electromagnetic waves with orbital angular momentum (OAM). Vortex electromagnetic waves are a divergent beam (the field strength in the middle area is very weak). Unlike plane waves and spherical waves, the wavefront of vortex electromagnetic waves is vortex-shaped, and the intensity of vortex waves in the axial direction is zero. This is caused by the interference destructiveness caused by the gradual change of the initial phase of each feeding unit. Therefore, the characteristics of vortex electromagnetic waves include the vortex nature of the phase and the conical distribution of the amplitude, forming a conical distribution vortex electric field with an axial electric field amplitude of 0, and at the same caliber, the divergence angles of vortex electromagnetic wave beams of different modes are different, so that they cannot be aimed at the same target. This has caused certain difficulties in the application of vortex waves.

[0003] Foreign research on vortex electromagnetic waves is relatively mature, from optics to radio fields, and involves everything from antennas to transmission, but the key problem of long-distance transmission of vortex electromagnetic waves due to beam divergence has not yet been solved; domestic research mainly follows foreign research, and the relative innovations are mainly concentrated in the design of antennas, and have not fundamentally solved the practical application problem of vortex electromagnetic waves, namely: the problem of beam divergence.

[0004] Looking at the current status of research on vortex electromagnetic waves at home and abroad, its transmission method still uses the traditional optical coaxial receiving method, that is, the receiving end receives all the signals on the entire phase plane at once in the direction of the electromagnetic wave propagation axis. This method will cause the size of the receiving antenna to increase rapidly with distance, and has no engineering application value for long-distance transmission. At present, research at home and abroad is focused on antennas, but if the beam divergence problem is not solved, the detection and imaging of vortex electromagnetic waves cannot be fundamentally solved from the antenna design alone. Therefore, it is necessary to first consider and find a solution to the problem of being unable to align with the target due to the divergence of the vortex electromagnetic wave beam. Summary of the invention

[0005] The present invention aims to provide a method for aligning arbitrary mode beams of vortex electromagnetic waves to the same target, so as to solve the problem that different modes of vortex electromagnetic waves have different divergence angles and thus the beams cannot be aligned to the same target.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] On the one hand, this specification provides a method for aligning a vortex electromagnetic wave arbitrary mode beam to the same target, comprising:

[0008] Acquire a target position in a phased array plane wave mode, and align the vortex electromagnetic wave beam axis with the target position;

[0009] According to the divergence angle of any mode of the vortex electromagnetic wave, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are determined;

[0010] According to the target position, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are converted to the antenna coordinate system;

[0011] According to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, the off-axis angle and the rotation angle of the vortex electromagnetic wave beam are calculated, and the pointing direction of the vortex electromagnetic wave beam is corrected.

[0012] On the other hand, the present specification also provides a device for aiming a vortex electromagnetic wave beam of any mode at the same target, comprising:

[0013] An axis alignment module is used to acquire a target position in a phased array plane wave mode and align the axis of the vortex electromagnetic wave beam to the target position;

[0014] A coordinate calculation module, used to determine the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system according to the divergence angle of any mode of the vortex electromagnetic wave;

[0015] A coordinate conversion module, used for converting the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system to the antenna coordinate system according to the target position;

[0016] The angle correction module is used to calculate the off-axis angle and rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, and correct the pointing direction of the vortex electromagnetic wave beam.

[0017] On the other hand, this specification also provides an electronic device,

[0018] A processor; and a memory arranged to store computer executable instructions, which when executed cause the processor to perform the steps of the method as claimed in any one of the preceding claims.

[0019] Based on the above technical solution, this specification can achieve the following technical effects:

[0020] The method for aiming the vortex electromagnetic wave arbitrary mode beam at the same target proposed in the present application includes: obtaining the target position in the phased array plane wave mode, and aligning the vortex electromagnetic wave beam axis with the target position; determining the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system according to the divergence angle of any mode of the vortex electromagnetic wave; converting the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system to the antenna coordinate system according to the target position; calculating the off-axis angle and rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, and correcting the pointing of the vortex electromagnetic wave beam. By introducing an auxiliary measurement coordinate system to set a certain angle to the vortex electromagnetic wave beam, any point on the annular beam is aligned with the target point, which solves the problem that the vortex electromagnetic wave beams of different modes cannot be aimed at the same target due to the different divergence angles of different modes of the vortex electromagnetic wave. Thereby, it can be achieved that the vortex electromagnetic waves of different modes can detect and image the same target point within the same phased array antenna aperture plane. The present application is mainly used in the fields of high-resolution imaging and target recognition of vortex electromagnetic wave radar. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of a method for aligning a vortex electromagnetic wave arbitrary mode beam with the same target provided in an embodiment of the present specification;

[0022] Figure 2 It is a schematic diagram of the principle of rotation of a vortex electromagnetic wave beam in an auxiliary coordinate system provided in an embodiment of this specification.

[0023] Figure 3 It is a schematic diagram of the relative position of the vortex electromagnetic wave beam axis P0 and the target P provided in an embodiment of this specification.

[0024] Figure 4 It is a schematic diagram of a device for aiming a vortex electromagnetic wave arbitrary mode beam at the same target provided by an embodiment of the present specification.

[0025] 1. Original vortex electromagnetic wave beam; 2. Target point P; 3. Rotated vortex electromagnetic wave beam; 4. Point P0 on the axis of the rotated vortex electromagnetic wave beam; 5. Divergence angle α l ; 6. Mode β; 7. Defined auxiliary measurement coordinate system; 701. Defined OX axis of the auxiliary measurement coordinate system; 702. Defined OY axis of the auxiliary measurement coordinate system; 703. Defined OZ axis of the auxiliary measurement coordinate system. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the drawings are all in very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0027] It should be noted that, in order to clearly explain the content of the present invention, the present invention specifically cites multiple embodiments to further illustrate different implementations of the present invention, wherein the multiple embodiments are enumerated rather than exhaustive. In addition, for the sake of brevity of explanation, the contents mentioned in the previous embodiments are often omitted in the subsequent embodiments. Therefore, the contents not mentioned in the subsequent embodiments can refer to the previous embodiments accordingly.

[0028] Example 1

[0029] Please refer to Figure 1 , Figure 1 FIG. 1 is a flow chart of a method for aligning a vortex electromagnetic wave beam of arbitrary mode to the same target provided by this embodiment. Figure 2 The figure shows the principle diagram of the rotation of the vortex electromagnetic wave beam in the auxiliary coordinate system provided by the present embodiment. The method specifically comprises the following steps:

[0030] Step 102: Acquire a target position in a phased array plane wave mode, and align the vortex electromagnetic wave beam axis with the target position.

[0031] It should be noted that one implementation of step 102 may be:

[0032] First, the position of the target is determined in the plane wave mode of the phased array, so that the axis of the vortex electromagnetic wave beam is aligned with the target.

[0033] Step 104: Determine the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system according to the divergence angle of any mode of the vortex electromagnetic wave.

[0034] It should be noted that one implementation of step 104 may be:

[0035] The divergence angle of any mode beam of vortex electromagnetic wave is α l ,β takes any value in the interval [0°,360°] of the annular beam;

[0036] Determine the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system as [x0 y0 z0], where x0 = cos(α l ), y0=sin(α l )cos(β), z0=sin(α l )sin(β).

[0037] Step 106: According to the target position, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are converted to the antenna coordinate system.

[0038] It should be noted that one implementation of step 106 may be:

[0039] According to the target position, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are converted to the missile body coordinate system:

[0040]

[0041] in, is the target azimuth, is the target pitch angle.

[0042] Convert the target pointing coordinates of the vortex electromagnetic wave beam in the missile body coordinate system to the antenna coordinate system:

[0043]

[0044] Step 108: Calculate the off-axis angle and rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, and correct the pointing direction of the vortex electromagnetic wave beam.

[0045] It should be noted that one implementation of step 108 may be:

[0046] According to the target pointing coordinates [x a0 y a0 z a0 ], calculate the off-axis angle θ0 and rotation angle of the vortex electromagnetic wave beam

[0047]

[0048] Among them, the off-axis angle θ0 and the rotation angle In x a0 <0: In x a0 >0,y a0 <0,

[0049] According to the calculated off-axis angle θ0 and rotation angle of the vortex electromagnetic wave beam Correct the pointing direction of the vortex electromagnetic wave beam.

[0050] In summary, the method for aligning any modal beam of vortex electromagnetic waves at the same target proposed in the present application introduces an auxiliary measurement coordinate system to set a certain angle for the vortex electromagnetic wave beam so that any point on the annular beam is aligned with the target point, thereby solving the problem that vortex electromagnetic wave beams of different modes cannot be aligned with the same target due to the different divergence angles of different modes of vortex electromagnetic waves. Thereby, it can be achieved that vortex electromagnetic waves of different modes can detect and image the same target point within the same phased array antenna aperture plane. The present application is mainly used in the fields of high-resolution imaging and target recognition of vortex electromagnetic wave radar.

[0051] Example 2

[0052] Please refer to Figure 2 , Figure 3 , Figure 2 FIG. 1 is a schematic diagram showing the principle of rotation of the vortex electromagnetic wave beam provided in this embodiment in the auxiliary coordinate system. Figure 3 Shown is a schematic diagram of the relative positions of the vortex electromagnetic wave beam axis P0 and the target P provided in this embodiment.

[0053] First, the position P2 of the target is determined in the plane wave mode of the phased array, and the axis of the original vortex electromagnetic wave beam 1 is aligned with the target P2. After the axis of the original vortex electromagnetic wave beam 1 is aligned with the target P2, the phased array is scanned at a certain angle to make the axis OP04 of the rotated vortex electromagnetic wave beam 3 point to the annular beam position of the original vortex electromagnetic wave beam 1, so that any point on the annular beam of any mode of the vortex electromagnetic wave can be aligned with the same target.

[0054] Among them, after scanning a certain angle by the phased array, the coordinates of the vortex wave beam axis OP0 in the auxiliary coordinate system 7 (OX axis 701 of the auxiliary measurement coordinate system, OY axis 702 of the auxiliary measurement coordinate system, OZ axis 703 of the auxiliary measurement coordinate system) are: x0 = cos (α l ), y0=sin(α l )cos(β), z0=sin(α l )sin(β). In the auxiliary coordinate system 7, the vortex electromagnetic wave beam is set at a certain angle α l 5 is equal to the divergence angle of each mode of the vortex electromagnetic wave, and β6 can be selected in the range of [0°, 360°].

[0055] After the vortex electromagnetic wave beam mode is aligned with the target P2, the axis points to the coordinate value [x i0 y i0 z i0 ]for:

[0056]

[0057] in, is the azimuth of the target P, is the pitch angle of the target P.

[0058] [x i0 y i0 z i0 ] is transformed to the antenna coordinate system to obtain the coordinate value of the beam pointing in the antenna coordinate system [x a0 y a0 z a0 ]for:

[0059]

[0060] By [x a0 y a0 z a0 ] Calculate the off-axis angle θ0 and the rotation angle required for the vortex electromagnetic wave to rotate for:

[0061]

[0062] Among them, the off-axis angle θ0 and the rotation angle In x a0 <0: In x a0 >0,y a0 <0,

[0063] Example 3

[0064] Please refer to Figure 4 , Figure 2 The figure shows a schematic diagram of a device for aiming a vortex electromagnetic wave beam of any mode at the same target provided by this embodiment. The device comprises:

[0065] An axis alignment module 302 is used to acquire a target position in a phased array plane wave mode and align the axis of the vortex electromagnetic wave beam to the target position;

[0066] A coordinate calculation module 304 is used to determine the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system according to the divergence angle of any mode of the vortex electromagnetic wave;

[0067] A coordinate conversion module 306 is used to convert the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system into the antenna coordinate system according to the target position;

[0068] The angle correction module 308 is used to calculate the off-axis angle and rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, and correct the pointing direction of the vortex electromagnetic wave beam.

[0069] In summary, the method for aligning any modal beam of vortex electromagnetic waves at the same target proposed in the present application introduces an auxiliary measurement coordinate system to set a certain angle for the vortex electromagnetic wave beam so that any point on the annular beam is aligned with the target point, thereby solving the problem that vortex electromagnetic wave beams of different modes cannot be aligned with the same target due to the different divergence angles of different modes of vortex electromagnetic waves. Thereby, it can be achieved that vortex electromagnetic waves of different modes can detect and image the same target point within the same phased array antenna aperture plane. The present application is mainly used in the fields of high-resolution imaging and target recognition of vortex electromagnetic wave radar.

[0070] Example 4

[0071] In another feasible embodiment, this embodiment provides a device for aiming vortex electromagnetic wave arbitrary mode beams at the same target, and the device may specifically include:

[0072] A processor; and a memory arranged to store computer executable instructions, which, when executed, cause the processor to perform the steps in any of the above method embodiments.

[0073] Example 5

[0074] In another feasible embodiment, this embodiment provides a storage medium for vortex electromagnetic wave arbitrary mode beams to be aimed at the same target, and the storage medium may specifically include:

[0075] The storage medium stores a processing program for aligning arbitrary modal beams of vortex electromagnetic waves to the same target. When the processing program for aligning arbitrary modal beams of vortex electromagnetic waves to the same target is executed by the processor, the steps in any of the above method embodiments are implemented.

[0076] The above description is only an embodiment of the present specification and is not intended to limit the present specification. For those skilled in the art, the present specification can be modified and varied in various ways. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present specification should be included in the scope of the claims of the present specification.

Claims

1. A method for aligning an arbitrary mode beam of a vortex electromagnetic wave to the same target, characterized in that: include: Acquire a target position in a phased array plane wave mode, and align the vortex electromagnetic wave beam axis with the target position; According to the divergence angle of any mode of the vortex electromagnetic wave, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are determined; According to the target position, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are converted to the antenna coordinate system; According to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, the off-axis angle and the rotation angle of the vortex electromagnetic wave beam are calculated, and the pointing direction of the vortex electromagnetic wave beam is corrected.

2. The method according to claim 1, characterized in that The method of determining the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system according to the divergence angle of any mode of the vortex electromagnetic wave comprises: The divergence angle of any mode beam of vortex electromagnetic wave is α l ,β takes any value in the interval [0°,360°] of the annular beam; Determine the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system as [x0 y0 z0], where x0 = cos(α l ), y0=sin(α l )cos(β), z0=sin(α l )sin(β).

3. The method according to claim 2, characterized in that The step of converting the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system to the antenna coordinate system according to the target position includes: According to the target position, the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system are converted to the missile body coordinate system; The target pointing coordinates of the vortex electromagnetic wave beam in the missile body coordinate system are converted to the antenna coordinate system.

4. The method according to claim 3, characterized in that: The step of converting the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system to the missile body coordinate system according to the target position includes: Calculated by the following formula: in, is the target azimuth, is the target pitch angle.

5. The method according to claim 4, characterized in that The step of converting the target pointing coordinates of the vortex electromagnetic wave beam in the missile body coordinate system to the antenna coordinate system includes: Calculated by the following formula:

6. The method according to claim 5, characterized in that The calculating the off-axis angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system includes: Calculated by the following formula:

7. The method according to claim 6, characterized in that The calculating the rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system includes: Calculated by the following formula:

8. The method according to claim 7, characterized in that The calculating the off-axis angle and the rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system comprises: In x a0 <0: In x a0 >0 and y a0 <0, 9. A device for aiming vortex electromagnetic wave beams of arbitrary modes at the same target, characterized in that: include: An axis alignment module is used to acquire a target position in a phased array plane wave mode and align the axis of the vortex electromagnetic wave beam to the target position; A coordinate calculation module, used to determine the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system according to the divergence angle of any mode of the vortex electromagnetic wave; A coordinate conversion module, used for converting the target pointing coordinates of the vortex electromagnetic wave beam in the auxiliary coordinate system to the antenna coordinate system according to the target position; The angle correction module is used to calculate the off-axis angle and rotation angle of the vortex electromagnetic wave beam according to the target pointing coordinates of the vortex electromagnetic wave beam in the antenna coordinate system, and correct the pointing direction of the vortex electromagnetic wave beam.

10. An electronic device, characterized in that: include: processor; and a memory arranged to store computer executable instructions which, when executed, cause the processor to perform the steps of the method as claimed in any one of claims 1 to 8.

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