Self-decoupling dual circularly polarized phased array arrangement method

Abstract

The invention discloses a self-decoupling dual circularly polarized phased array arrangement method, the array scale of a phased array is not less than 4 rows and 2 columns, the method comprises the following steps: selecting one row in the phased array as an initial row, the other rows are not the initial row, and all antenna units of the initial row adopt the same arrangement mode; odd-even grouping is carried out on the antenna units in the initial row, initial rotation modes of an odd number group and an even number group are defined, the initial rotation mode of one group is clockwise rotation, and the initial rotation mode of the other group is anticlockwise rotation; and antenna units and adjacent units in the phased array rotate in different sequences. On the premise that the basic performance of the array is guaranteed, a remarkable decoupling effect is achieved, and the polarization requirement of the DCP array is met.

Description

Technical Field

[0001] The present application belongs to the technical field of phased array antenna design, and in particular relates to a self-decoupling dual circularly polarized phased array arrangement method. Background Art

[0002] Phased array antennas (PAAs) have fast and accurate beam steering capabilities, enabling wide scanning angles and bandwidths. Circularly polarized antennas are resistant to polarization mismatch, multipath interference, and Faraday rotation effects. Circularly polarized phased array antennas currently have very broad application prospects in satellite communications and radar systems. To meet the application needs of new-era satellite communication technologies, phased array antennas need to have excellent isolation and reusable antenna array surfaces. However, traditional phased arrays suffer from problems such as poor isolation and low antenna aperture utilization due to the influence of the array arrangement.

[0003] Improving the isolation of phased array antennas can be achieved by introducing neutral lines, array-antenna decoupling surfaces (ADS), and other parasitic structures. However, the introduction of additional parasitic structures significantly increases the difficulty of phased array antenna array and element design, and also affects the performance of the phased array, such as reduced scanning angle and poor element matching. In addition, to improve the aperture utilization efficiency of the antenna and increase the channel capacity of the antenna, the phased array needs to have the polarization characteristics of dual circular polarization (DCP). However, the traditional sequential rotation array can only be used in single circular polarization phased arrays and cannot meet the polarization requirements of DCP.

[0004] The existing technology, "Dual-Circularly Polarized Phased Array With Modified Cavity and Notched Patch," discloses a dual-circularly polarized wide-angle scanning PAA. It includes a dual-circularly polarized patch antenna unit operating in the K band and a conventional rectangular periodic PAA. The antenna unit consists of a double-layer chamfered rectangular patch and a rectangular cavity. The proposed DCP-PAA has a bandwidth of 18.8 to 20 GHz (1.2 GHz) and can cover a scanning angle of ±60°. However, due to the conventional rectangular periodic array arrangement, its minimum isolation is only 15 dB.

[0005] The existing technology "K- / Ka-Band Planar Shared-Aperture Beam-Scanning Array Antenna for Simultaneous Transmitting and Receiving Low Earth Orbit Satellite Communication Terminal" discloses a dual-band dual circularly polarized common aperture antenna for low-orbit satellite communications. The antenna is right-hand circularly polarized (RHCP) from 17.7 to 21.2 GHz and left-hand circularly polarized (LHCP) from 27.5 to 31.0 GHz. The antenna can cover a scanning angle of ±60° in both frequency bands, and the voltage standing wave ratio (VSWR) is less than 3dB. However, this technology can only operate in a single circular polarization form in a single frequency band, and does not have the polarization characteristics of a single-band DCP. There are great limitations in terms of channel capacity and aperture multiplexing.

[0006] The existing technology, "Design of Low Mutual Coupling Dielectric Resonator Antennas Without Using Extra Decoupling Element," discloses a port self-decoupling technology for dielectric resonant antennas. By stimulating specific high-order modes, which can be excited by active dielectric resonant antennas but not by the feed network, the mutually coupled energy is prevented from being transferred to the feed network ports, thereby achieving port decoupling. This design can achieve a maximum isolation improvement of 13dB. However, this technology can only optimize isolation within a narrow bandwidth and is only applicable to one type of antenna element, dielectric resonant antennas, which has significant limitations.

[0007] As satellite communications and radar technologies require phased array antennas to have high isolation, broadband, and high aperture utilization, current technology is unable to meet the above requirements simultaneously. Summary of the Invention

[0008] The purpose of this application is to overcome the shortcomings of the existing technology and provide a self-decoupling dual circularly polarized phased array arrangement method, which combines spin angular momentum with antenna array arrangement and introduces a new degree of freedom for array arrangement through unit spin in the array.

[0009] The purpose of this application is achieved through the following technical solutions:

[0010] A method for arranging a self-decoupling dual circularly polarized phased array, wherein the array size of the phased array is not less than 4 rows and 2 columns, the method comprising:

[0011] A row is selected in the phased array as an initial row, and the other rows are non-initial rows, wherein all antenna units in the initial row are arranged in the same manner;

[0012] The antenna elements of the initial row are grouped into odd and even groups, and the initial rotation modes of the odd and even groups are defined, where the initial rotation mode of one group is clockwise and the initial rotation mode of the other group is counterclockwise.

[0013] The antenna units in the phased array are rotated in a different order from the adjacent units.

[0014] Furthermore, the rotation angle of the antenna unit is (N-1)*90°, where N is the number of rows of the current antenna unit, with the initial row being the first row.

[0015] Furthermore, each antenna unit of the phased array includes a transmitting / receiving component, which is used to independently adjust the amplitude and phase.

[0016] Furthermore, the digital phase shift number of the transmitting / receiving component is not less than 4.

[0017] Furthermore, the arrangement of the phased array includes a rectangular periodic arrangement, a triangular periodic arrangement or a non-periodic arrangement.

[0018] Furthermore, the radiation form of the antenna unit includes an end-fire radiation form or a side-fire radiation form.

[0019] Furthermore, the antenna units of the phased array independently adjust the rotation direction of the circular polarization from the feeding end.

[0020] The beneficial effects of this application are:

[0021] (1) This application is based on the theory of spin angular momentum. According to the performance requirements of the phased array antenna, after determining the initial row units and odd-even unit groupings in the array, the units are rotated in the array arrangement, thereby introducing spin angular momentum into the array arrangement. By rotating units in different rows and positions in different ways, the clockwise and counterclockwise sequential rotation components are integrated into a phased array antenna array, solving the problem that the traditional sequential rotation arrangement method cannot be used for dual circularly polarized phased arrays.

[0022] (2) This application fully considers the performance of the units of the phased array antenna, giving the unit design greater freedom and lower port decoupling requirements. It can achieve a significant improvement in other performance by sacrificing some port isolation, fully reducing the design difficulty of the DCP-PAA array, and effectively avoiding the isolation of unit design and array design.

[0023] (3) According to the principle of generating circularly polarized electromagnetic waves, there will be a high isolation effect between the clockwise and counterclockwise rotating units in the present application.

[0024] (4) The units in the phased array of the present application are rotated in a different order from the adjacent units, so the self-decoupling effect between the units is achieved through the array arrangement.

[0025] (5) The arrangement method proposed in this application has no strict requirements on the overall layout of the array. This method can be used for arrays with periodic or non-periodic arrangements. Rectangular periodic arrangements and triangular periodic arrangements can also use this method to optimize array performance, which has good practicality and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of a 4×4 scale of a self-decoupling dual circularly polarized phased array arrangement method according to an embodiment of the present application;

[0027] Figure 2 3 is a schematic diagram comparing a self-decoupling dual circularly polarized phased array arrangement method in an embodiment of the present application with a traditional arrangement method, wherein. Figure 2 (a) is a schematic diagram of a self-decoupling dual circularly polarized phased array arrangement method. Figure 2 (b) is a schematic diagram of the traditional arrangement;

[0028] Figure 3 This is a schematic diagram comparing the unit isolation between a self-decoupling dual circularly polarized phased array arrangement method and a traditional arrangement method in an embodiment of the present application;

[0029] Figure 4 : This is a schematic diagram comparing the scanning performance of a self-decoupling dual circularly polarized phased array arrangement method and a traditional arrangement method in an embodiment of the present application, wherein: Figure 4 (a) is a schematic diagram of the scanning performance of a self-decoupling dual circularly polarized phased array arrangement method. Figure 4 (b) Schematic diagram of the scanning performance of the traditional arrangement. DETAILED DESCRIPTION

[0030] The following describes the embodiments of the present application through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0031] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0032] Existing phased array antennas are required to have high isolation, broadband, and high aperture utilization performance, but current technology makes it difficult to meet the above requirements simultaneously.

[0033] In order to solve the above technical problems, the present application proposes the following embodiments of a self-decoupling dual circularly polarized phased array arrangement method.

[0034] In the embodiment of the present application, angular momentum is introduced as a new degree of freedom to optimize the design of the array through the spin of the units in the array, and the spin follows an arrangement rule that combines clockwise and counterclockwise rotation sequences.

[0035] First, based on the design requirements, the DCP unit design was completed, and the scale of the DCP-PAA array was determined to be N×N. The DCP-PAA performance requirements primarily included dual circular polarization, port isolation, gain, and scanning angle. Within the determined DCP-PAA array, a combination of clockwise and counterclockwise rotation was employed.

[0036] Taking one antenna unit in the array as the reference, a coordinate system is established, and the relative position of the Nth DCP unit is defined as (x n ,y n ), the rotation angle of the Nth unit relative to the first unit is θ n , the order of the antenna units in this embodiment is:

[0037] The first cell on the left of the initial row (the first row) is 1. After counting the first row, continue counting from the first cell on the left of the second row, and so on.

[0038] A row in the array is designated as the initial row, and all cells in this initial row adopt the same arrangement, without any cell rotation. The cells in the initial row are grouped, for example, using an odd-even grouping scheme. Odd-numbered cells are defined as initial cells that rotate clockwise, optimizing the array's right-hand circular polarization radiation. Even-numbered cells are defined as initial cells that rotate counterclockwise, optimizing the array's left-hand circular polarization radiation.

[0039] For the second row of antenna units, the same odd-even grouping method is used, and the staggered rotation method is used with the first row. The odd-numbered units are rotated counterclockwise, and the unit rotation angle is θ n =-90°; the even-numbered units rotate clockwise, and the unit spin angle is θ n =+90°.

[0040] According to the staggered rotation arrangement rule, odd rows use the same grouping method as the initial row, that is, odd-numbered units are rotated clockwise, and even-numbered units are rotated counterclockwise. The spin angle of the antenna unit is (N-1)*90°, where N is the number of rows of the current antenna unit with the initial row as the first row. For example, the spin angle of the antenna unit in the third row is (3-1)*90°=180°.

[0041] It should be noted that the subarray size must be at least four rows and two columns, which is the minimum subarray size required to support both clockwise and counterclockwise rotation. The array size must be at least one subarray size, meaning the number of rows must be at least four and the number of columns must be at least two. The total array size does not need to be an integer multiple of the subarray size (2N×4N); it only needs to be larger than one subarray. The larger the array size, the stronger the self-decoupling capability of this embodiment's arrangement.

[0042] This embodiment verifies the decoupling capability of the proposed array through the cut-corner circularly polarized patch antenna, which has a good decoupling effect compared with the conventional phased array. This embodiment achieves the self-decoupling effect of the units in the array by adding spin angular momentum to the array units and combining two sequential rotations. The designed DCP-PAA array arrangement can achieve an isolation improvement of more than 3.8dB within the entire operating frequency band. In addition, the arrangement of this embodiment includes an arrangement that conforms to the polarization characteristics of both left-handed and right-handed circular polarization, so it can meet the optimization of two different circular polarization types in one array, realize the reuse of the array surface, and improve the efficiency of antenna aperture utilization.

[0043] The following is an example of a 4×4 array. Figure 1 ,like Figure 1 The figure shows a 4×4 scale schematic diagram of a self-decoupling dual circularly polarized phased array arrangement method according to an embodiment of the present application. In this array, the first row from top to bottom is the initial row, and the units in the first row adopt the same arrangement method. Figure 1 The 2×4 array marked by the red frame is the smallest sub-array of the arrangement described in the embodiment of the present application.

[0044] After determining the initial rows of the array, the initial rows are grouped into odd and even bits, such as Figure 1 As shown in the numbers marked in the red box; after completing the unit grouping in the sub-array, the unit is spun to achieve port self-decoupling and optimize the polarization performance of the DCP array.

[0045] More specifically, the specific method of unit rotation is that the initial row of units does not rotate, and the second row of units rotates in a counterclockwise order of -90° according to the arrangement rule, and the even-numbered units rotate clockwise by +90°, such as Figure 1 As shown in units 3 and 4 marked in the red box.

[0046] The third row of units is rotated in an alternating pattern with the second row, with the odd-numbered units rotating clockwise by +180° and the even-numbered units rotating counterclockwise by -180°. Figure 1 As shown in the red box marked units 5 and 6; similarly, the fourth row units and the third row units are rotated alternately, the odd-numbered units are rotated counterclockwise by -270°, and the even-numbered units are rotated clockwise by +270°, as shown in the figure. Figure 1 As shown in units 7 and 8 marked in the red box.

[0047] Figure 1 In the basic sub-array shown, units 1, 4, 5, and 8 are sub-array components that rotate in counterclockwise order, and units 2, 3, 6, and 7 are sub-array components that rotate in clockwise order. The two sub-array components with different rotation directions can optimize the radiation performance of the DCP. After completing the rotation arrangement of the basic sub-array, Figure 1 The subarray marked by the red frame is copied and evenly spaced to the right, thus expanding the array from a 2×4 scale to a 4×4 scale. Arrays of other scales can be arranged by simply following the above arrangement method and arranging the corresponding unit spins.

[0048] In the embodiment of the present application, the difference in array performance between the rectangular circular polarization patch unit arrangement according to the present invention and the traditional arrangement is also compared. Figure 2 ,like Figure 2 The figure shows a comparison diagram of a self-decoupling dual circularly polarized phased array arrangement method according to an embodiment of the present application and a traditional arrangement method, wherein. Figure 2 (a) is a schematic diagram of a self-decoupling dual circularly polarized phased array arrangement method. Figure 2 (b) is a schematic diagram of the traditional arrangement.

[0049] Through software simulation, the array performance of the two arrangements was verified and compared. The arrangement provided by the embodiment of the present application has an excellent self-decoupling effect and achieves a port isolation improvement of more than 3.8dB within the working frequency band. Figure 3 ,like Figure 3 The figure shows a comparison of the unit isolation between a self-decoupling dual circularly polarized phased array arrangement method and a traditional arrangement method according to an embodiment of the present application. The minimum isolation of the two arrangements is 18.70dB and 14.86dB respectively.

[0050] In addition, compared with the scanning performance of the traditional arrangement, the arrangement provided by the embodiment of the present application has a scanning range of ±50°, and the arrangement provided by the embodiment of the present application is superior to the traditional phased array arrangement in terms of sidelobe level (SLL), and the array SLL can be further improved by amplitude weighting. Figure 4 ,like Figure 4 The figure shows a comparison of the scanning performance of a self-decoupling dual circularly polarized phased array arrangement method and a traditional arrangement method according to an embodiment of the present application, wherein: Figure 4 (a) is a schematic diagram of the scanning performance of a self-decoupling dual circularly polarized phased array arrangement method. Figure 4 (b) Schematic diagram of the scanning performance of the traditional arrangement.

[0051] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A self-decoupling dual circular polarization phased array arrangement method, characterized in that: The array size of the phased array is not less than 4 rows and 2 columns, and the method comprises: A row is selected in the phased array as an initial row, and other rows are non-initial rows, and all antenna units in the initial row are arranged in the same manner; The antenna elements of the initial row are grouped into odd and even groups, and the initial rotation modes of the odd group and the even group are defined, wherein the initial rotation mode of one group is clockwise rotation, and the initial rotation mode of the other group is counterclockwise rotation; The antenna units and adjacent units in the phased array are rotated in different orders.

2. The self-decoupling dual circular polarization phased array arrangement method according to claim 1, characterized in that: The rotation angle of the antenna unit is (N-1)*90°, where N is the number of rows of the current antenna unit, with the initial row as the first row.

3. The self-decoupling dual circular polarization phased array arrangement method according to claim 1, characterized in that: Each antenna unit of the phased array includes a transmitting / receiving component, and the transmitting / receiving component is used to independently adjust the amplitude and phase.

4. The self-decoupling dual circular polarization phased array arrangement method according to claim 3, characterized in that: The digital phase shift number of the transmitting / receiving component is not less than 4.

5. The self-decoupling dual circular polarization phased array arrangement method according to claim 1, characterized in that: The arrangement of the phased array includes rectangular periodic arrangement, triangular periodic arrangement or non-periodic arrangement.

6. The self-decoupling dual circular polarization phased array arrangement method according to claim 1, characterized in that: The radiation form of the antenna unit includes an end-fire radiation form or a side-fire radiation form.

7. The self-decoupling dual circular polarization phased array arrangement method according to claim 1, characterized in that: The antenna units of the phased array independently adjust the rotation direction of circular polarization from the feeding end.

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