Method for controlling directional diagram of multi-frequency laminated microstrip antenna

Abstract

The invention relates to the technical field of antennas, in particular to a method for controlling a directional diagram of a multi-frequency laminated microstrip antenna, and the method is realized based on the multi-frequency laminated microstrip antenna. The grounding substrate is fixed at the top of the metal array disc through a plurality of second metal screws, and the grounding substrate and the metal array disc are concentrically and coaxially arranged; according to the method for controlling the directional diagram of the multi-frequency laminated microstrip antenna disclosed by the invention, the antenna can cover S, L and B3 frequency bands of the third generation of Beidou, the directional diagram of the multi-frequency laminated microstrip antenna is controlled through the annular beam forming array, and the directional diagram of the multi-frequency laminated microstrip antenna is controlled through the annular beam forming array. According to the antenna, the application requirements of various Beidou No.3 navigation terminal devices can be met, and meanwhile, the problem that a directional diagram of a corresponding antenna frequency is sunken at a vertex (Theta = 0 degree) in an environment in which the metal reflection ground area is far larger than two times of wavelength can be solved.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and more particularly to a method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna. Background Art

[0002] With the continuous construction and improvement of the Beidou satellite navigation system, its application scope in the market is constantly expanding. As an indispensable key component of the navigation system, the performance of the Beidou antenna is directly related to the performance of various practical functions of the Beidou satellite navigation system, especially in the regional short message communication downlink S-band service provided by the Beidou satellite navigation system. It involves geosynchronous orbit satellites, which are mainly distributed near the equator. Therefore, when the Beidou satellite application terminal needs to use the communication function in different areas, special attention must be paid to the orientation of the antenna, which undoubtedly limits certain scenarios of Beidou applications. Beidou navigation terminals have a wide range of application scenarios, which put forward diverse requirements for antenna performance. These requirements include but are not limited to the antenna bandwidth, gain at various elevation angles, and propagation directivity. In specific application scenarios, the antenna may need to have a specific bandwidth to support high-speed data transmission, or need to provide higher gain at certain elevation angles to ensure stable signal reception. At the same time, the antenna directivity also needs to be adjusted according to the application scenario to meet the specific requirements for signal coverage and propagation path; However, these diverse requirements pose a huge challenge to antenna design, especially when using multi-frequency stacked microstrip antennas. When the area of ​​the metal reflector is larger than twice the wavelength corresponding to the antenna frequency, a specific problem will arise: the antenna radiation pattern of the corresponding frequency will be concave at the vertex (i.e., theta=0°). This phenomenon will seriously affect the performance of the antenna, especially in application scenarios that require high directivity and high gain. Summary of the invention

[0003] 1. Technical issues to be resolved The purpose of the present invention is to solve the following technical problems: In order to cope with the diversified demands for the elevation gain of Beidou antennas in different application scenarios, and the problem of a depression at the vertex (theta=0°) of the antenna radiation pattern of the corresponding frequency appearing in a multi-frequency stacked microstrip antenna under a specific environment (the metal reflection area is larger than twice the wavelength size of the antenna frequency), the present invention provides a method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna. The method achieves precise control of the gain radiation pattern of the microstrip antenna by utilizing beamforming array technology, thereby enabling the antenna to flexibly adapt to various application scenarios and effectively solve the problem of gain depression.

[0004] (II) Technical solution The present invention is implemented through the following technical solution: The present invention proposes a method for controlling the directional pattern of a multi-frequency stacked microstrip antenna, the method is implemented based on a multi-frequency stacked microstrip antenna, the antenna comprising: Metal array plate; A grounding substrate is fixed to the top of the metal array plate by a plurality of second metal screws and is arranged concentrically and coaxially with the metal array plate; The B3 band antenna is placed on top of the grounded substrate and is arranged concentrically and coaxially to achieve right-hand circular polarization; The L-band antenna is set concentrically and coaxially on top of the B3-band antenna to achieve left-hand circular polarization; The S-band antenna is set concentrically and coaxially on top of the L-band antenna to achieve right-hand circular polarization; There are three RF connectors, which are arranged at the bottom of the ground substrate and are respectively connected to the B3 band antenna, the L band antenna and the S band antenna and are grounded; The annular beamforming array comprises a first metal screw, an array dielectric circular plate and a plurality of array radiation units; The shaped array medium circular plate is arranged on the top of the metal array plate through a plurality of first metal screws, and is arranged concentrically and coaxially; A plurality of array radiation units are arranged at equal intervals on the top of the array dielectric circular plate along the circumferential direction of the array dielectric circular plate, and the array radiation units surround the ground substrate; The array radiation unit is configured as a square-shaped microstrip patch; A pair of diagonally opposite corners of the radiating element of the array adopts a chamfered design; A groove is designed in the middle of the array radiation unit, and the opening direction of the groove faces the outer edge of the array medium circular plate; The middle parts of the four sides of the array radiation unit are designed to bulge outwards, and each bulge is provided with a structure of a rectangular groove opening inwards; The method for controlling the radiation pattern of the multi-frequency stacked microstrip antenna specifically comprises the following steps: I) Determine the frequency point f of each radiating element in the annular beamforming array to adjust the directivity pattern. The frequency point f is achieved by adjusting the width w of the radiating element of the annular beamforming array. According to the formula: It is calculated that, is the speed of light, is the dielectric constant of the array dielectric circular plate, and the width w is the side length of the array radiation unit; II) Determine the number of radiating elements of each shape in the annular beamforming array to adjust the directivity pattern; III) Determine the distance d between each radiating element in the annular beamforming array and the S-band antenna to adjust the radiation pattern. The formula is d , λ is the wavelength received by the multi-frequency stacked microstrip antenna, where , c and f are the same as step III).

[0005] Preferably, the B3 frequency band antenna comprises a B3 frequency band microstrip patch, a B3 frequency band dielectric circular plate and a B3 frequency band feeding network; The B3 band feeding network is located at the bottom of the grounded substrate; The B3 frequency band dielectric circular plate is placed on the top of the ground substrate by pasting water-retaining glue on the back side, and is arranged concentrically and coaxially; A B3 band microstrip patch is provided on the top of the B3 band dielectric circular plate, and is arranged concentrically and coaxially; The B3 band microstrip patch is connected to the B3 band feeding network by penetrating the B3 band dielectric circular plate and the ground substrate through the probe coaxial feeding method to achieve right-hand circular polarization. The B3 band feeding network is connected to the RF connector and grounded; An L-band antenna is provided on the top of the B3-band dielectric disc.

[0006] Preferably, the L-band antenna comprises an L-band microstrip patch, an L-band dielectric circular plate and an L-band feeding network; The L-band feeding network is located at the bottom of the grounded substrate; The L-band dielectric circular plate is placed on top of the B3-band dielectric circular plate by pasting water-retaining glue on the back, and the arrangement is coaxial and concentric; The L-band microstrip patch is arranged on the top of the L-band dielectric circular plate and is arranged concentrically and coaxially; The L-band microstrip patch is connected to the L-band feeding network by coaxial feeding of the probe through the L-band dielectric circular plate, the B3-band dielectric circular plate, the ground substrate, and realizes left-hand circular polarization. The L-band feeding network is connected to the RF connector and grounded; An S-band antenna is arranged on the top of the L-band dielectric disc.

[0007] Preferably, the S-band antenna comprises an S-band microstrip patch, an S-band dielectric circular plate and an S-band feeding network; The S-band feeding network is located at the bottom of the grounded substrate; The S-band dielectric circular plate is placed on the top of the L-band dielectric circular plate by pasting water-retaining glue on the back side, and the arrangement is coaxial and concentric; The S-band microstrip patch is arranged on the top of the S-band dielectric circular plate and is arranged concentrically and coaxially; The S-band microstrip patch is connected to the S-band feeding network by coaxial feeding of the probe through the S-band dielectric circular plate, the L-band dielectric circular plate, the B3-band dielectric circular plate, the ground substrate, and the S-band feeding network to achieve right-hand circular polarization. The S-band feed network is connected to the RF connector and grounded.

[0008] Preferably, the adjustment range of the frequency point f is 2.492 GHz±10 MHz.

[0009] Preferably, the number of array radiation units is 4-8.

[0010] Preferably, the value range of d is 60±1 mm.

[0011] Preferably, four first metal screws and four second metal screws are provided.

[0012] Preferably, a gap is provided between the ground substrate and the array medium circular plate.

[0013] Preferably, the ground substrate and the array medium circular plate are both made of glass fiber reinforced epoxy resin material.

[0014] (III) Beneficial effects The present invention discloses a method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna. The antenna can cover the S, L, and B3 frequency bands of the BeiDou-3. The radiation pattern of the multi-frequency stacked microstrip antenna is controlled by an annular beamforming array to meet the application requirements of various BeiDou-3 navigation terminal devices. At the same time, it can also solve the problem that the radiation pattern of the corresponding antenna frequency appears concave at the vertex (theta=0°) when the area of ​​the metal reflection ground is much larger than 2 times the wavelength. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings: Figure 1 It is a structural schematic diagram of the present invention.

[0016] Figure 2 It is a bottom view structural schematic diagram of the ground substrate of the present invention.

[0017] Figure 3 This is a schematic diagram of the gain curve of the S-band center frequency band (2.492MHz) without the addition of a circular beamforming array.

[0018] Figure 4 This is a schematic diagram of the gain curve of the L-band center frequency band (1.616GHz) without the addition of a circular beamforming array.

[0019] Figure 5 Schematic diagram of the gain curve of the B3 center frequency band (1.268GHz) without the addition of the circular beamforming array.

[0020] Figure 6 This is a schematic diagram of the gain curve of the S-band center frequency band (2.492GHz) in the debugging state of the ring beamforming array.

[0021] Figure 7This is a schematic diagram of the gain curve of the L-band center frequency band (1.616GHz) in the debugging state of the circular beamforming array.

[0022] Figure 8 This is a schematic diagram of the gain curve of the B3 band center frequency band (1.268GHz) in the debugging state of the circular beamforming array.

[0023] Fig. 9 This is a schematic diagram of the gain curve of the S-band center frequency band (2.492GHz) in the debugging state of the ring beamforming array.

[0024] Fig.10 This is a schematic diagram of the gain curve of the L-band center frequency band (1.616GHz) in the debugging state of the ring beamforming array.

[0025] Fig.11 This is a schematic diagram of the gain curve of the B3 frequency band center band (1.268GHz) in the debugging state 2 of the annular beamforming array.

[0026] Figure markings: 1-metal array plate, 2-shaped array dielectric circular plate, 3-shaped array radiation unit, 4-B3 band microstrip patch, 5-first metal screw, 6-second metal screw, 7-S band microstrip patch, 8-S band dielectric circular plate, 9-L band microstrip patch, 10-L band dielectric circular plate, 11-B3 band dielectric circular plate, 12-ground substrate, 13-gap, 14-B3 band feeding network, 15-S band feeding network, 16-L band feeding network, 17-RF connector, Q-annular beamforming array, ES band antenna, FL band antenna, H-B3 band antenna. DETAILED DESCRIPTION

[0027] The present invention is implemented through the following technical solution: The present invention proposes a method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna, and the method is implemented based on a multi-frequency stacked microstrip antenna. Figure 1 and Figure 2 As shown, the antenna comprises: Metal array plate; A grounding substrate is fixed to the top of the metal array plate by a plurality of second metal screws and is arranged concentrically and coaxially with the metal array plate; The B3 band antenna is placed on top of the grounded substrate and is arranged concentrically and coaxially to achieve right-hand circular polarization; The L-band antenna is set concentrically and coaxially on top of the B3-band antenna to achieve left-hand circular polarization; The S-band antenna is set concentrically and coaxially on top of the L-band antenna to achieve right-hand circular polarization; There are three RF connectors, which are arranged at the bottom of the ground substrate and are respectively connected to the B3 band antenna, the L band antenna and the S band antenna and are grounded; The annular beamforming array comprises a first metal screw, an array dielectric circular plate and a plurality of array radiation units; The shaped array medium circular plate is arranged on the top of the metal array plate through a plurality of first metal screws, and is arranged concentrically and coaxially; A plurality of array radiation units are arranged at equal intervals on the top of the array dielectric circular plate along the circumferential direction of the array dielectric circular plate, and the array radiation units surround the ground substrate; The array radiation unit is configured as a square-shaped microstrip patch; A pair of diagonally opposite corners of the radiating element of the array adopts a chamfered design; A groove is designed in the middle of the array radiation unit, and the opening direction of the groove faces the outer edge of the array medium circular plate; The middle parts of the four sides of the array radiation unit are designed to bulge outwards, and each bulge is provided with a structure of a rectangular groove opening inwards; The method for controlling the radiation pattern of the multi-frequency stacked microstrip antenna specifically comprises the following steps: I) Determine the frequency point f of each radiating element in the annular beamforming array to adjust the directivity pattern. The frequency point f is achieved by adjusting the width w of the radiating element of the annular beamforming array. According to the formula: It is calculated that, is the speed of light, is the dielectric constant of the array dielectric circular plate, and the width w is the side length of the array radiation unit; II) Determine the number of radiating elements of each shape in the annular beamforming array to adjust the directivity pattern; III) Determine the distance d between each radiating element in the annular beamforming array and the S-band antenna to adjust the radiation pattern. The formula is d , λ is the wavelength received by the multi-frequency stacked microstrip antenna, where , c and f are the same as steps a.

[0028] Wherein, the B3 frequency band antenna comprises a B3 frequency band microstrip patch, a B3 frequency band dielectric circular plate and a B3 frequency band feeding network; The B3 band feeding network is located at the bottom of the grounded substrate; The B3 frequency band dielectric circular plate is placed on the top of the ground substrate by pasting water-retaining glue on the back side, and is arranged concentrically and coaxially; A B3 band microstrip patch is provided on the top of the B3 band dielectric circular plate, and is arranged concentrically and coaxially; The B3 band microstrip patch is connected to the B3 band feeding network by penetrating the B3 band dielectric circular plate and the ground substrate through the probe coaxial feeding method to achieve right-hand circular polarization. The B3 band feeding network is connected to the RF connector and grounded; An L-band antenna is provided on the top of the B3-band dielectric disc.

[0029] Wherein, the L-band antenna includes an L-band microstrip patch, an L-band dielectric circular plate and an L-band feeding network; The L-band feeding network is located at the bottom of the grounded substrate; The L-band dielectric circular plate is placed on top of the B3-band dielectric circular plate by pasting water-retaining glue on the back, and the arrangement is coaxial and concentric; The L-band microstrip patch is arranged on the top of the L-band dielectric circular plate and is arranged concentrically and coaxially; The L-band microstrip patch is connected to the L-band feeding network by coaxial feeding of the probe through the L-band dielectric circular plate, the B3-band dielectric circular plate, the ground substrate, and realizes left-hand circular polarization. The L-band feeding network is connected to the RF connector and grounded; An S-band antenna is arranged on the top of the L-band dielectric disc.

[0030] Wherein, the S-band antenna comprises an S-band microstrip patch, an S-band dielectric circular plate and an S-band feeding network; The S-band feeding network is located at the bottom of the grounded substrate; The S-band dielectric circular plate is placed on the top of the L-band dielectric circular plate by pasting water-retaining glue on the back side, and the arrangement is coaxial and concentric; The S-band microstrip patch is arranged on the top of the S-band dielectric circular plate and is arranged concentrically and coaxially; The S-band microstrip patch is connected to the S-band feeding network by coaxial feeding of the probe through the S-band dielectric circular plate, the L-band dielectric circular plate, the B3-band dielectric circular plate, the ground substrate, and the S-band feeding network to achieve right-hand circular polarization. The S-band feed network is connected to the RF connector and grounded.

[0031] The B3 band antenna, the L band antenna, and the S band antenna can achieve the frequency points required by their respective antennas by changing the dielectric constants of their respective dielectric circular plates and the shapes of their respective microstrip patches.

[0032] The adjustment range of the frequency point f is 2.492 GHz ± 10 MHz.

[0033] Among them, the number of array radiation units is 4-8.

[0034] Among them, the value range of d is 60±1mm.

[0035] There are four first metal screws and four second metal screws.

[0036] Wherein, a gap is provided between the ground substrate and the array medium circular plate.

[0037] Wherein, the ground substrate and the array medium circular plate are both made of glass fiber reinforced epoxy resin material.

[0038] The following is an analysis of the various components and their functions in the invention: Metal array plate and ground substrate The metal array plate serves as the base of the entire antenna and provides a stable supporting structure. The grounding substrate is fixed to the top of the metal array plate by a number of second metal screws and is coaxially arranged with the metal array plate, thereby ensuring the stability of the antenna and the accuracy of signal transmission. The presence of the grounding substrate also helps the grounding and signal shielding of the antenna and reduces external interference. B3, L, S band antennas B3, L, and S band antennas are responsible for signal transmission in different frequency bands. The antenna of each frequency band is composed of a microstrip patch, a dielectric disc, and a feeding network. The microstrip patch is a radiation element responsible for radiating electromagnetic waves or receiving electromagnetic waves from space. The dielectric disc supports the microstrip patch and adjusts the antenna performance. The feeding network is responsible for transmitting signals from the RF connector to the microstrip patch, or receiving signals from the microstrip patch and transmitting them back to the RF connector. The B3 band antenna realizes right-hand circular polarization, the L band antenna realizes left-hand circular polarization, and the S band antenna realizes right-hand circular polarization again. This design enables the antenna to process signals of multiple frequency bands at the same time and meet different polarization requirements; RF Connectors The RF connectors are located at the bottom of the ground substrate and are connected to the B3, L, and S band antennas and grounded. They are responsible for transmitting the signals received by the antennas to external devices, or transmitting the signals sent by external devices to the antennas. The existence of the RF connectors ensures that the signal transmission between the antennas and external devices is stable and reliable. Circular Beamforming Array The annular beamforming array is composed of a first metal screw, an array dielectric circular plate and a plurality of array radiating units. The array radiating units are arranged at equal intervals along the circumference of the array dielectric circular plate and surround the ground substrate. The antenna directivity pattern is adjusted by adjusting the frequency point, number and distance of these radiating units from the S-band antenna. The design of the radiating element of the shaped array is very unique, including the chamfered corners, the groove in the middle, the four sides protruding outwards, and the rectangular slot structure inwards at each protrusion. These designs help optimize the performance of the antenna and improve the accuracy and stability of the radiation pattern. Adjustment of frequency, quantity and distance By adjusting the frequency, number and distance of the array radiating unit from the S-band antenna, the antenna pattern can be precisely controlled. The frequency adjustment range is limited to 2.492GHz±10MHz to ensure stable performance of the antenna within a specific frequency band. The number of array radiating units is limited to 4-8 to balance the performance and complexity of the antenna. The distance from the S-band antenna is determined according to the wavelength d value range (60±1mm) to ensure that the antenna works in the best condition. Other design details There are four first metal screws and four second metal screws to ensure the stability and structural integrity of the antenna. A gap is provided between the ground substrate and the array dielectric circular plate to help reduce reflection and interference inside the antenna. The ground substrate and the array dielectric circular plate are both made of glass fiber reinforced epoxy resin material, which has excellent mechanical and electrical properties and can meet the antenna's material requirements.

[0039] In order to verify the effect of the circular beamforming array on the radiation pattern of the multi-frequency microstrip stacked antenna, we conducted the following experiments: Experimental Example 1: Using any of the above multi-frequency microstrip stacked antennas without the circular beamforming array, we first measured the results without the circular beamforming array ( Figure 3 , Figure 4 , Figure 5 As shown in the figure, the gain of the S-band antenna at elevation angles of 90°, 40°, and 60°. The experimental results show that the gain at an elevation angle of 90° is 0.64dBi, the gain at an elevation angle of 40° is 4.3dBi, and the gain at an elevation angle of 60° is 1.21dBi. It can be seen that the gain is low at the vertex (theta=0°, i.e., an elevation angle of 90°), and a concave problem occurs; Experimental Example 2: Use any of the above multi-frequency microstrip stacked antennas including a circular beamforming array and adjust it to state 1 (obtain Figure 6 , Figure 7 and Figure 8 As shown in the figure): the frequency point f=2482GHz of each radiating element in the annular beamforming array is determined, the number of radiating elements in each radiating element in the annular beamforming array is determined to be 6, and the distance d between each radiating element in the annular beamforming array and the S-band antenna is determined to be 59.8mm; the experimental results show that the gain at an elevation angle of 90° is increased to 4.81dBi, the gain at an elevation angle of 40° is 3.93dBi, and the gain at an elevation angle of 60° is 1.26dBi. Compared with the array without annular beamforming, the gain at the vertex is significantly improved, and the sag problem is effectively improved; Experimental Example 3: Use any of the above multi-frequency microstrip stacked antennas including a circular beamforming array; Finally, we adjust the circular beamforming array to state 2 again (obtain Fig. 9 , Fig.10 and Fig.11 As shown in the figure): the frequency point f=2492GHz of each radiating element in the annular beamforming array is determined, the number of radiating elements in each radiating element in the annular beamforming array is determined to be 6, and the distance d between each radiating element in the annular beamforming array and the S-band antenna is determined to be 59.5mm; the experimental results show that the gain at an elevation angle of 90° is further improved to 7.26dBi, the gain at an elevation angle of 40° is 4.29dBi, and the gain at an elevation angle of 60° is 0.83dBi. In state two, the gain at the vertex reaches the highest value, and the gain at other elevation angles also remains relatively stable.

[0040] Arrange the table:

[0041] Therefore, these data not only verify the effective control of the annular beamforming array on the antenna pattern, but also show how it can be flexibly adjusted according to specific application requirements. At the same time, these data also show that in an environment where the metal reflection area is much larger than 2 times the wavelength, by adding the annular beamforming array and adjusting its parameters, the problem of the concave antenna frequency pattern at the vertex (theta=0°) can be effectively solved, thereby improving the overall performance of the antenna. Therefore, these data can be regarded as the results of the verification method and also as the basis for demonstrating the practical application effect of the annular beamforming array in antenna design.

Claims

1. A method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna, characterized in that: The method is implemented based on a multi-frequency stacked microstrip antenna, which includes: Metal array plate (1); A grounding substrate (12) is fixed to the top of the metal array plate (1) by means of a plurality of second metal screws (6) and is arranged concentrically and coaxially with the metal array plate (1); A B3 frequency band antenna (H) is disposed on the top of a grounded substrate (12) and is arranged concentrically and coaxially to achieve right-hand circular polarization; The L-band antenna (F) is coaxially arranged on top of the B3-band antenna (H) to achieve left-hand circular polarization; The S-band antenna (E) is placed concentrically and coaxially on top of the L-band antenna (F) to achieve right-hand circular polarization; Three radio frequency connectors (17) are provided, which are arranged at the bottom of the ground substrate (12) and are respectively connected to the B3 frequency band antenna (H), the L frequency band antenna (F) and the S frequency band antenna (E) and are grounded; A circular beamforming array (Q) comprises a first metal screw (5), an array dielectric circular plate (2) and a plurality of array radiation units (3); The array medium circular plate (2) is arranged on the top of the metal array plate (1) through a plurality of first metal screws (5) and is arranged concentrically and coaxially; A plurality of array radiation units (3) are arranged at equal intervals on the top of the array dielectric circular plate (2) along the circumferential direction of the array dielectric circular plate (2), and the array radiation units (3) surround the ground substrate (12); The array radiation unit (3) is configured as a square-shaped microstrip patch; A pair of diagonally opposite corners of the array radiation unit (3) are designed with chamfered corners; A groove is designed in the middle of the array radiation unit (3), and the opening direction of the groove faces the outer edge of the array medium circular plate (2); The middle parts of the four sides of the array radiation unit (3) are designed to bulge outwards, and each bulge is provided with a structure of a rectangular groove opening inwards; The method for controlling the radiation pattern of the multi-frequency stacked microstrip antenna specifically comprises the following steps: I) Determine the frequency point f of each shaped array radiating element (3) in the annular beamforming array (Q) to adjust the directivity pattern. The frequency point f is achieved by adjusting the width w of the shaped array radiating element (3) according to the formula: It is calculated that, is the speed of light, is the dielectric constant of the array dielectric circular plate (2), and the width w is the side length of the array radiation unit (3); II) determining the number of radiating elements (3) of each annular beamforming array (Q) to adjust the directivity pattern; III) Determine the distance d between each radiating element in the annular beamforming array (Q) and the S-band antenna (E) to adjust the radiation pattern. The formula is d , λ is the wavelength received by the multi-frequency stacked microstrip antenna, where , c and f are the same as step III).

2. A method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 1, characterized in that: The B3 frequency band antenna (H) comprises a B3 frequency band microstrip patch (4), a B3 frequency band dielectric circular plate (11) and a B3 frequency band feeding network (14); The B3 frequency band feeding network (14) is arranged at the bottom of the ground substrate (12); The B3 frequency band dielectric circular plate (11) is arranged on the top of the ground substrate (12) by means of a back surface adhesively bonded with water-retaining glue, and is arranged coaxially and concentrically; A B3 frequency band microstrip patch (4) is provided on the top of the B3 frequency band dielectric circular plate (11) and is arranged coaxially and concentrically; The B3 frequency band microstrip patch (4) penetrates the B3 frequency band dielectric circular plate (11), the ground substrate (12) and is connected to the B3 frequency band feeding network (14) by means of probe coaxial feeding, thereby achieving right-hand circular polarization; The B3 frequency band feeding network (14) is connected to the radio frequency connector (17) and is grounded; An L-band antenna (F) is arranged on the top of the B3-band dielectric circular plate (11).

3. A method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 2, characterized in that: The L-band antenna (F) comprises an L-band microstrip patch (9), an L-band dielectric circular plate (10) and an L-band feeding network (16); The L-band feeding network (16) is arranged at the bottom of the ground substrate (12); The L-band dielectric circular plate (10) is arranged on the top of the B3-band dielectric circular plate (11) by pasting water-retaining glue on the back thereof, and is arranged coaxially and concentrically; The L-band microstrip patch (9) is arranged on the top of the L-band dielectric circular plate (10) and is arranged concentrically and coaxially; The L-band microstrip patch (9) penetrates the L-band dielectric circular plate (10), the B3-band dielectric circular plate (11), and the ground substrate (12) and is connected to the L-band feeding network (16) by means of probe coaxial feeding, thereby achieving left-hand circular polarization; The L-band feeding network (16) is connected to the radio frequency connector (17) and is grounded; An S-band antenna (E) is arranged on the top of the L-band dielectric circular plate (10).

4. A method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 3, characterized in that: The S-band antenna (E) comprises an S-band microstrip patch (7), an S-band dielectric circular plate (8) and an S-band feeding network (15); The S-band feeding network (15) is arranged at the bottom of the ground substrate (12); The S-band dielectric circular plate (8) is arranged on the top of the L-band dielectric circular plate (10) by pasting water-retaining glue on the back side, and is arranged coaxially and concentrically; The S-band microstrip patch (7) is arranged on the top of the S-band dielectric circular plate (8) and is arranged concentrically and coaxially; The S-band microstrip patch (7) penetrates the S-band dielectric circular plate (8), the L-band dielectric circular plate (10), the B3-band dielectric circular plate (11), and the ground substrate (12) and is connected to the S-band feeding network (15) by means of probe coaxial feeding, thereby achieving right-hand circular polarization; The S-band feeding network (15) is connected to the radio frequency connector (17) and is grounded.

5. The method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 1, characterized in that: The adjustment range of the frequency point f is 2.492 GHz ± 10 MHz.

6. The method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 1, characterized in that: The number of the array radiation units (3) is 4-8.

7. A method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 1, characterized in that: The value range of d is 60±1mm.

8. The method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 2, characterized in that: There are four first metal screws (5) and four second metal screws (6).

9. The method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 1, characterized in that: A gap (13) is provided between the ground substrate (12) and the array medium circular plate (2).

10. The method for controlling the radiation pattern of a multi-frequency stacked microstrip antenna according to claim 1, characterized in that: The grounding substrate (12) and the array medium circular plate (2) are both made of glass fiber reinforced epoxy resin material.

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