Phased array ka-band dual-polarized microstrip antenna array

Abstract

The invention discloses a phased array ka-band dual-polarized microstrip antenna array, and relates to the field of communication antennae, the antenna array comprises an antenna layer and a feeder line layer located at the bottom of the antenna layer, the antenna layer comprises a first dielectric substrate and a rhombic patch array arranged at the top of the first dielectric substrate; the feeder line layer comprises a second dielectric substrate and a coaxial feed network arranged at the top of the second dielectric substrate, and the coaxial feed network feeds each diamond patch of the diamond patch array through a via hole; the radiation performance of the microstrip antenna in the ka wave band is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of communication antennas, and in particular to a phased array Ka-band dual-polarized microstrip antenna array. Background Art

[0002] The rapid development of wireless communication technology, particularly the growing demand for high-speed data transmission and high-resolution radar systems, has placed higher demands on antennas capable of operating in higher frequency ranges. The Ka-band (typically referring to the 26.5 to 40 GHz frequency range) exhibits significant potential in satellite communications, space exploration, weather radar, and 5G millimeter-wave communications due to its wide bandwidth and compact size.

[0003] Currently, the design of Ka-band antennas mainly relies on traditional waveguide, horn antenna or microstrip patch antenna technologies. However, these technologies have certain limitations:

[0004] Traditional waveguide and horn antennas: Although these antennas have high gain and good directivity, they are usually large and difficult to integrate into modern portable or compact devices;

[0005] Conventional microstrip patch antennas: Microstrip patch antennas are favored for their planar structure, ease of fabrication, and compatibility with printed circuit board technology. However, conventional microstrip antennas have poor radiation performance in the Ka-band. Summary of the Invention

[0006] The purpose of this application is to provide a phased array Ka-band dual-polarization microstrip antenna array, which can improve the radiation performance of the microstrip antenna in the Ka-band.

[0007] To achieve the above objectives, this application provides the following solutions:

[0008] In a first aspect, the present application provides a phased array Ka-band dual-polarized microstrip antenna array, comprising an antenna layer and a feeder layer located at the bottom of the antenna layer, wherein:

[0009] The antenna layer includes a first dielectric substrate and a diamond patch array arranged on top of the first dielectric substrate;

[0010] The feeder layer includes a second dielectric substrate and a coaxial feeding network arranged on top of the second dielectric substrate. The coaxial feeding network feeds each diamond patch of the diamond patch array through a via hole.

[0011] Optionally, the diamond patch array adopts an 8×8 diamond patch array;

[0012] The distance between two adjacent diamond-shaped patches is 5 mm.

[0013] Optionally, the coaxial feeding network feeds each of the diamond patches at ±45°.

[0014] Optionally, the coaxial feeding network uses 16 1-to-4 power splitters to perform +45° or -45° feeding.

[0015] Optionally, each of the 1-to-4 power splitters is connected to an external transmitting module or receiving module via an SMPM connector.

[0016] Optionally, each output end of each of the 1-to-4 power splitters is fed by a wavy feed line and two corresponding diamond-shaped patches, wherein:

[0017] Each output end of each of the 1-to-4 power dividers is connected to the crest of the wavy feeder, and the two diamond patches are correspondingly connected to the two troughs of the wavy feeder away from the crest through vias.

[0018] Optionally, the pads of the SMPM connector are arranged on both sides of the feeder network of 16 1-to-4 power splitters.

[0019] Optionally, the first dielectric substrate and the second dielectric substrate are both Rogers RO3003 substrates.

[0020] Optionally, the first dielectric substrate and the second dielectric substrate are bonded together by prepreg.

[0021] Optionally, the phased array Ka-band dual-polarized microstrip antenna array operates in a frequency band of 34 GHz to 36 GHz.

[0022] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0023] The present application provides a phased array Ka-band dual-polarized microstrip antenna array, which realizes layered array integration by using independent dielectric substrates for the antenna layer and the feed layer, reduces inter-layer signal crosstalk, simplifies the processing technology, improves the yield rate, and supports high-frequency signal integrity; by using diamond patches in the antenna layer, the mutual coupling between patches is effectively reduced, cross interference is reduced, the symmetry of the antenna pattern is improved, and beam distortion is reduced; after simulation, the isolation between adjacent units of the phased array Ka-band dual-polarized microstrip antenna array reaches more than 27dB, the cross-polarization isolation reaches more than 20dB, the normal gain is greater than 23.6dB within the frequency band, and the scanning range within the frequency band reaches ±45° with a sidelobe level ≤-10dBc, which effectively improves the radiation performance of the microstrip antenna in the Ka-band and solves the problem of poor radiation performance of conventional microstrip antennas in the Ka-band. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 This is a schematic structural diagram of a phased array Ka-band dual-polarization microstrip antenna unit in one embodiment of the present application;

[0026] Figure 2 for Figure 1 Simulated radiation pattern of the phased array Ka-band dual-polarized microstrip antenna unit;

[0027] Figure 3 for Figure 1 The simulated standing wave ratio diagram of the phased array Ka-band dual-polarization microstrip antenna unit;

[0028] Figure 4 A first structural diagram of a phased array Ka-band dual-polarized microstrip antenna array provided in one embodiment of the present application;

[0029] Figure 5 A second structural diagram of a phased array Ka-band dual-polarized microstrip antenna array provided in one embodiment of the present application;

[0030] Figure 6 for Figure 4 S-parameter simulation diagram of the phased array Ka-band dual-polarized microstrip antenna array (without coaxial feeding network);

[0031] Figure 7 for Figure 4 34GHz simulated normal radiation pattern of the phased array Ka-band dual-polarized microstrip antenna array (without coaxial feed network);

[0032] Figure 8 for Figure 4 35GHz simulated normal radiation pattern of the phased array Ka-band dual-polarized microstrip antenna array (without coaxial feed network);

[0033] Figure 9 for Figure 4 36GHz simulated normal pattern of the phased array Ka-band dual-polarized microstrip antenna array (without coaxial feed network);

[0034] Figure 10 for Figure 4 Scanning characteristic diagram of the phased array Ka-band dual-polarized microstrip antenna array (without coaxial feeding network);

[0035] Figure 11A schematic diagram of a feeding network structure of a phased array ka-band dual-polarized microstrip antenna array provided by an embodiment of the present application;

[0036] Figure 12 A schematic diagram of a feeding network structure of a phased array ka-band dual-polarized microstrip antenna array provided by an embodiment of the present application; Figure 11 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0037] Figure 13 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0038] Figure 14 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0039] Figure 15 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0040] Figure 16 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0041] Figure 17 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0042] Figure 18 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0043] Figure 19 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0044] Figure 20 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0045] Figure 21 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0046] Figure 22 A schematic diagram of a structure of an SMPM connector connected by the feeding network;

[0047] Figure 23 The 36 GHz normalized radiation pattern test results of the phased array Ka-band dual-polarization microstrip antenna array (with coaxial feed network) provided in one embodiment of the present application. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0049] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0050] In an exemplary embodiment, a phased array Ka-band dual-polarized microstrip antenna unit is provided, such as Figure 1 As shown in the figure, the antenna substrate uses the Rogers RO3003 substrate (PTFE ceramic material with good thermal expansion coefficient, low plate warping risk, and dielectric constant εr of 3) with stable performance. The thickness is 0.508mm. In order to improve the symmetry of the antenna radiation pattern, reduce beam distortion, and facilitate feeder routing, the patches on the antenna substrate are diamond patches, and the feeder is coaxially fed at +45° or -45°.

[0051] In the embodiment of the present application, the simulated directional pattern of the dual-polarized microstrip antenna unit is as follows: Figure 2 As shown, the standing wave Figure 3 As shown in the figure, the antenna operates in the Ka-band (26.5GHz to 40GHz), with a bandwidth covering 33.66GHz to 36.02GHz and a unit gain of 7dB.

[0052] In an exemplary embodiment, Figures 4-5 As shown, a phased array Ka-band dual-polarized microstrip antenna array is provided, comprising an antenna layer and a feeder layer located at the bottom of the antenna layer. The antenna layer comprises a first dielectric substrate and a diamond patch array disposed on top of the first dielectric substrate. The feeder layer comprises a second dielectric substrate and a coaxial feed network disposed on top of the second dielectric substrate. The coaxial feed network feeds each diamond patch in the diamond patch array through a via.

[0053] In this embodiment, diamond-shaped patches are used to effectively reduce the mutual coupling between patches in the diamond-shaped patch array, reducing cross-interference, improving antenna pattern symmetry, and reducing beam distortion, while also facilitating feeder routing. The antenna layer and feeder layer utilize separate dielectric substrates, enabling layered array integration. This reduces inter-layer signal crosstalk, simplifies processing, improves yield, and maintains high-frequency signal integrity.

[0054] In another exemplary embodiment of the present application, the diamond patch array adopts an 8×8 diamond patch array, and the distance between two adjacent diamond patches is 5 mm.

[0055] In the embodiment of the present application, the miniaturization of the phased array Ka-band dual-polarized microstrip antenna array is achieved while improving the radiation performance. The spacing between two adjacent diamond patches refers to the distance between the centers of the two adjacent diamond patches.

[0056] The S-parameter simulation results of the 8×8 phased array Ka-band dual-polarized microstrip antenna array without a coaxial feed network are shown in Figure 2. Figure 6 As shown, the simulation results of the normal radiation patterns at 34GHz, 35GHz and 36GHz are as follows Figures 7 to 9 As shown. Figure 6 It can be seen from the figure that the isolation between adjacent elements of the 8×8 phased array Ka-band dual-polarized microstrip antenna array reaches more than 27dB, and the cross-polarization isolation reaches more than 20dB. Figures 7 to 9 It can be seen that the normal gain of the 8×8 phased array Ka-band dual-polarization microstrip antenna array is greater than 23.6 dB within the frequency band, and the first sidelobe is less than -13.2 dBc within the frequency band.

[0057] Due to symmetry, the 8×8 phased array Ka-band dual-polarized microstrip antenna array is examined for scanning at 0°, 15°, 30°, and 45° (to evaluate the ability and performance of the phased array Ka-band dual-polarized microstrip antenna array to perform beam steering at these specific angles. By changing the phase or time delay of the signal fed to each antenna element, the main beam of the antenna array can be directed to 0°, 15°, 30°, and 45°). The radiation pattern is shown in the figure below. Figure 10 As shown in the figure, the phase shift accuracy of the six phase shifters is considered, meaning that the feed phase can only be an integer multiple of 5.625°. It can be seen that the array antenna scans within the frequency band to a ±45° range with a sidelobe level ≤ -10dBc.

[0058] In another exemplary embodiment of the present application, the coaxial feeding network feeds each diamond patch at ±45°.

[0059] In the embodiment of the present application, each diamond patch is fed at ±45°, which allows the phased array Ka-band dual-polarized microstrip antenna array to operate simultaneously in the two polarization states of +45 degrees and -45 degrees within the same frequency band, thereby enhancing the flexibility, efficiency and anti-interference capability of the system.

[0060] In another exemplary embodiment of the present application, in order to achieve high isolation in a limited array space, the coaxial feeding network uses 16 1-to-4 power splitters to perform +45° or -45° feeding.

[0061] In another exemplary embodiment of the present application, considering the limited array size, the bending and dense arrangement of feed lines will bring unexpected coupling and crosstalk. Therefore, in order to suppress high-frequency coupling and achieve high isolation in a limited array space, the feed lines of the coaxial feed network are optimized. During the design, the antenna and feeder are integrated and optimized step by step. The optimized feed line arrangement is as follows: Figure 11 As shown by the green connecting line, according to Figure 11 It can be seen that each output end of each 1-to-4 power splitter is fed with the corresponding two diamond patches through a wavy feeder. Specifically, each output end of each 1-to-4 power splitter is connected to the crest of the wavy feeder, and the corresponding two diamond patches are connected to the two troughs of the wavy feeder away from the crest of the wavy feeder through vias.

[0062] In another exemplary embodiment of the present application, each diamond-shaped patch is connected to the BGA pad of the corresponding wavy feed line through a via.

[0063] In the embodiment of the present application, each diamond-shaped patch is connected to the BGA pad of the corresponding wavy feeder through a via, which ensures connection reliability while providing better electrical performance.

[0064] In another exemplary embodiment of the present application, in order to ensure that the connection between the phased array Ka-band dual-polarized microstrip antenna array and the external transmitting module or receiving module is efficient, reliable and adaptable to high-frequency operation, each 1-to-4 power splitter is connected to the external receiving module or transmitting module through an SMPM connector.

[0065] In another exemplary embodiment of the present application, in order to achieve high isolation and suppress high-frequency coupling in a limited array space, the pads of the SMPM connector are set on both sides of the feeder network of 16 1-to-4 power splitters, such as Figure 13 The red pads shown are pads of the SMPM connector. Each pad of the SMPM connector is connected to the metal layer at the bottom of the second dielectric substrate through a via.

[0066] In the embodiment of the present application, the Figure 11 The structure of the SMPM connector structure on the pads shown is as follows Figure 12 shown.

[0067] In another exemplary embodiment of the present application, most of the substrate materials currently suitable for microstrip antennas exhibit high dielectric loss in the Ka-band, which further reduces the overall efficiency of the antenna. Based on this, the embodiment of the present application sets the first dielectric substrate and the second dielectric substrate to both use Rogers RO3003 substrates.

[0068] In the embodiment of the present application, the Rogers RO3003 substrate has the advantages of low warping risk and adaptability to temperature changes in aerospace environments. It has low dielectric loss in the Ka-band and improves the overall efficiency of the antenna.

[0069] In another exemplary embodiment of the present application, the first and second dielectric substrates are bonded together via a prepreg (PP) layer. In addition to bonding, the prepreg provides electrical insulation, preventing short circuits between different layers. By selecting a prepreg with an appropriate dielectric constant and thickness, the characteristic impedance of the signal line can be precisely controlled, which is particularly important for high-frequency signal transmission.

[0070] In another exemplary embodiment of the present application, the thickness of the first dielectric substrate is 0.508 mm, the thickness of the second dielectric substrate is 0.254 mm, the thickness of the prepreg layer is 0.1 mm, and the dielectric constant of the prepreg layer is 2.7.

[0071] In another exemplary embodiment of the present application, the above-mentioned via hole is a metal through hole, and the metal through hole passes through the prepreg layer.

[0072] In another exemplary embodiment of the present application, in order to realize the test verification of the phased array Ka-band dual-polarized microstrip antenna array, an 8×8 phased array Ka-band dual-polarized microstrip antenna array is designed, and 16 1-to-4 power splitters are used for +45° or -45° feeding, and the size is consistent with that during system integration.

[0073] The simulation test results of 8×8 phased array Ka-band dual-polarized microstrip antenna array are shown in Figures 13 and 14 As shown. Figures 13 and 14 As shown in the figure, within the frequency band (34 GHz to 36 GHz), the feed ports of the 16 1-to-4 power splitters are well matched, with gains reaching 22.06 dBi, 22.29 dBi, and 22.59 dBi at 34 GHz, 35 GHz, and 36 GHz, respectively. The first sidelobe level is less than -10 dB. Considering that the loss of the 1-to-4 power splitter is about 1 dB, the actual gain of the 8×8 phased array Ka-band dual-polarized microstrip antenna array is greater than 23 dBi without considering the power divider loss.

[0074] Array test:

[0075] 1. Antenna standing wave test

[0076] Test location: Laboratory 547, Building 1, Telecommunications Building, Shanghai Jiao Tong University;

[0077] Test instruments: Keysight N5227A vector network analyzer, k1.85 coaxial RF cable, AV20206M calibration kit;

[0078] Test method: Set the S parameter to S11, the intermediate frequency bandwidth to 1kHz, and the frequency to 32-38GHz on the vector network analyzer, and perform calibration tests. Calibrate the open circuit, short circuit, and matched load components respectively. Then replace the calibration components with samples for S parameter testing. Figure 15 shown.

[0079] Test results: The S11 parameters of all 16 ports are less than -11.7dB (corresponding to a standing wave ratio of 1.7). Figure 16 shown.

[0080] 2. Antenna gain pattern test

[0081] Test location: Microwave anechoic room 517, Building 1, Shanghai Jiao Tong University Telecommunications Building;

[0082] Test instruments: CETC41 vector network analyzer, millimeter wave controller, standard antenna;

[0083] Test method: Use Shanghai Jiaotong University millimeter wave sub-terahertz integrated antenna test system (with CMA qualification) to test antenna array indicators. Figure 17 Configure the test standard gain antenna pattern, press Figure 18 The antenna pattern to be tested is configured, where the antenna to be tested is the 8×8 phased array Ka-band dual-polarized microstrip antenna array of the embodiment of the present application. The active pattern synthesis method is used to synthesize the full array pattern, and the pattern when the 16 ports are fed is tested separately, such as Figures 19 and 20 During the test, all non-powered ports were terminated with 50Ω loads. This accurately simulates actual operating conditions, avoids the effects of port mutual coupling, and supports efficient testing of large-scale arrays (8×8 arrays).

[0084] Test results: See the test normalized pattern results. Figures 21 to 23 The test gains at 34GHz, 35GHz and 36GHz reached 22.2dBi, 22.4dBi and 22.5dBi respectively. Considering that the loss of the 1-to-4 power divider is about 1dB, the actual gain of the antenna array is greater than 23dBi without considering the power divider loss, and the first sidelobe level is ≤-10dBc (normal).

[0085] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0086] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A phased array Ka-band dual-polarized microstrip antenna array, characterized in that: The phased array Ka-band dual-polarized microstrip antenna array includes an antenna layer and a feeder layer located at the bottom of the antenna layer, wherein: The antenna layer includes a first dielectric substrate and a diamond patch array arranged on top of the first dielectric substrate; The feeder layer includes a second dielectric substrate and a coaxial feeding network arranged on top of the second dielectric substrate. The coaxial feeding network feeds each diamond patch of the diamond patch array through a via hole.

2. The phased array Ka-band dual-polarized microstrip antenna array according to claim 1, characterized in that: The diamond patch array adopts an 8×8 diamond patch array; The distance between two adjacent diamond-shaped patches is 5 mm.

3. The phased array Ka-band dual-polarized microstrip antenna array according to claim 1, characterized in that: The coaxial feeding network feeds each of the diamond-shaped patches at ±45°.

4. The phased array Ka-band dual-polarized microstrip antenna array according to claim 3, characterized in that: The coaxial feeding network uses 16 1-to-4 power splitters to perform +45° or -45° feeding.

5. The phased array Ka-band dual-polarized microstrip antenna array according to claim 4, characterized in that: Each of the 1-to-4 power splitters is connected to an external transmitting module or receiving module via an SMPM connector.

6. The phased array Ka-band dual-polarized microstrip antenna array according to claim 4, characterized in that: Each output end of each of the 1-to-4 power splitters is fed by a wavy feed line and two corresponding diamond patches, wherein: Each output end of each of the 1-to-4 power dividers is connected to the crest of the wavy feeder, and the two diamond patches are correspondingly connected to the two troughs of the wavy feeder away from the crest through vias.

7. The phased array Ka-band dual-polarized microstrip antenna array according to claim 5, characterized in that: The pads of the SMPM connector are arranged on both sides of the feeder network of 16 1-to-4 power splitters.

8. The phased array Ka-band dual-polarized microstrip antenna array according to claim 1, characterized in that: The first dielectric substrate and the second dielectric substrate are both Rogers RO3003 substrates.

9. The phased array Ka-band dual-polarized microstrip antenna array according to claim 1, characterized in that: The first dielectric substrate and the second dielectric substrate are bonded together by prepreg.

10. The phased array Ka-band dual-polarized microstrip antenna array according to claim 1, characterized in that: The operating frequency band is 34GHz~36GHz.

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