Grounding miniaturized oscillator circularly polarized satellite communication antenna

Abstract

The invention discloses a grounded miniaturized oscillator circularly polarized satellite communication antenna, and belongs to the technical field of satellite communication antennae, an upper-layer radiator comprises four triangular aluminum plates with the same size, a lower-layer radiator comprises four trapezoidal aluminum plates with the same size, and the upper-layer radiator and the lower-layer radiator are separated by a gap. The nylon support is of a hollow hemisphere structure and is used for stably supporting other structures such as the upper-layer radiator and the lower-layer radiator. The lower radiator and the grounding plate are in short-circuit connection through the short-circuit pin. The number of the horizontal soldering lug and the number of the vertical soldering lug are respectively used for feeding the two pairs of orthogonally-polarized upper-layer radiators, the two radio frequency connectors are respectively connected to two inlets of the impedance matcher through one radio frequency line with the same length, and an outlet of the impedance matcher is connected to two inlets of the circular polarizer through two radio frequency lines with the same length. The antenna has the advantages of being wide in frequency band, small in size, light in weight, easy to produce in batches and the like.

Description

Technical Field

[0001] This invention relates to an antenna in the field of satellite communication technology, and particularly to a grounded miniaturized oscillator circularly polarized satellite communication antenna. Background Technology

[0002] With the continuous development of satellite communication technology, miniaturized and unmanned platforms are also rapidly increasing. Under the trend of platform miniaturization, equipment miniaturization is also an inevitable trend. At the same time, platforms face the need for multi-functional integration and simultaneous operation across multiple frequency bands. Driven by this need, equipment miniaturization has become an effective means of achieving this. Antennas, as the medium for exchanging electromagnetic energy with space, function to transmit or receive signals. According to the antenna's working principle, the antenna's operating frequency is closely related to its physical size. How to effectively reduce the antenna's physical size without sacrificing antenna gain is a challenge in miniaturized antenna design. Summary of the Invention

[0003] In view of this, the present invention provides a grounded miniaturized oscillator circularly polarized satellite communication antenna, which has the characteristics of wide bandwidth, small size, light weight and easy mass production.

[0004] To achieve the above objectives, the solution adopted by the present invention is as follows: A grounded miniaturized oscillator circularly polarized satellite communication antenna includes an upper radiator (1), a lower radiator (2), and a nylon support (3); the upper radiator (1) and the lower radiator are both covered on the outer surface of the nylon support (3); The nylon support (3) is a hollow hemispherical structure, and the upper radiator (1) covers the top of the hollow hemispherical structure. It consists of four upper radiating patches; the four upper radiating patches are arranged in a circular array, and the upper radiating patches facing each other are connected by corresponding solder pads. The lower radiator (2) consists of four lower radiating patches, which correspond one-to-one with the four upper radiating patches. The lower radiating patches are located below the corresponding upper radiating patches. The bottom edge of the lower radiating patch is attached to the bottom edge of the hollow hemispherical structure. There is a gap between the top edge of the lower radiating patch and the bottom edge of the upper radiating patch. The bottom of the nylon support (3) is provided with a grounding plate (7), and the lower radiator is short-circuited to the grounding plate (7) through a short-circuit pin (4); Each solder pad is connected to the corresponding RF connector (10) via the corresponding feed cable (8); the RF connector (10) is connected to the circular polarizer (11) via the impedance matching device (12).

[0005] Furthermore, the upper radiating patch is a triangular aluminum plate, and the lower radiating patch is a trapezoidal aluminum plate.

[0006] Furthermore, each lower radiation patch is connected to the ground plane (7) via two short-circuit pins (4).

[0007] Furthermore, there are gaps between adjacent radiating patches.

[0008] Furthermore, the two solder pads are used to feed two pairs of orthogonally polarized upper radiators (1), with one end of the solder pad being soldered to the corresponding upper radiator patch and the other end being soldered to the inner conductor of the feed cable (8).

[0009] Furthermore, there are two RF connectors (10), two feed cables (8) of equal length, and two solder pads are each connected to the corresponding RF connector (10) through a feed cable (8) of equal length. The two RF connectors (10) are each connected to the two inputs of the impedance matching device (12) through a RF line of equal length. The output of the impedance matching device (12) is connected to the two inputs of the circular polarizer (11) through two RF lines of equal length.

[0010] Furthermore, the impedance matching device (12) includes a matching device housing (13), an impedance matching circuit (14), and an RF connector X (15); the impedance matching circuit (14) and the RF connector X (15) are both located inside the matching device housing (13); The impedance matching circuit (14) has two circuits, both of which are double-sided PCB circuits. The main body of the double-sided PCB circuit is a dielectric substrate (17). A microstrip network (16) is etched on the dielectric substrate (17). The four SMA connectors of the RF connector X (15) are connected to the microstrip network, two of which are inputs and the other two are outputs.

[0011] The beneficial effects of the above-described solution in this invention are as follows: This invention employs grounding and impedance matching techniques to design a miniaturized circularly polarized antenna. The overall shape is hemispherical, with a cross-sectional height of 140mm (0.15λmax), smaller than the typical 0.2λmax, and a width of 220mm (0.24λmax), smaller than the typical 0.4λmax, achieving overall antenna miniaturization. Miniaturized antennas have wide applications, especially on airborne or shipborne platforms, fully utilizing limited space to improve equipment efficiency and enhance functionality. This invention's antenna exhibits a voltage standing wave ratio (VSWR) of less than 2.5, a circular polarization axial ratio of less than 2dB, and a gain greater than 4dBi within its operating frequency band. It features wide bandwidth, small size, light weight, and ease of mass production. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the oblique view structure according to an embodiment of the present invention; Figure 2 This is a side view structural diagram of an embodiment of the present invention.

[0013] Figure 3 This is a schematic diagram of an impedance matching device according to an embodiment of the present invention.

[0014] Figure 4 This is an impedance matching circuit diagram according to an embodiment of the present invention.

[0015] Figure 5 This is a standing wave ratio curve diagram of an embodiment of the present invention.

[0016] Figure 6 This is a 330MHz gain pattern (0° cross-section) of an embodiment of the present invention.

[0017] Figure 7 This is a 330MHz gain pattern (90° cross-section) of an embodiment of the present invention.

[0018] Figure 8 This is a 330MHz circular polarization axial ratio pattern (left-handed polarization) according to an embodiment of the present invention.

[0019] Figure 9 This is a 330MHz circular polarization axial ratio pattern (right-handed polarization) according to an embodiment of the present invention. Detailed Implementation

[0020] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. It is understandable to those skilled in the art that certain well-known structures and their descriptions may be omitted in the accompanying drawings.

[0021] A grounded, miniaturized circularly polarized satellite communication antenna is based on a cross-shaped dipole antenna. Through grounding and matching circuit design, the physical size of the antenna is significantly reduced while still meeting broadband operation requirements. The antenna operates in the UHF band, with a low-frequency resonant boundary point reaching 330MHz. Using a VSWR below 2.5 as a benchmark, the relative bandwidth reaches 37%. The antenna can directionally radiate dual-circularly polarized electromagnetic waves along the center of the antenna axis.

[0022] The grounded miniaturized circularly polarized satellite antenna used in this invention includes an upper radiator 1, a lower radiator 2, a nylon support 3, a shorting pin 4, a horizontal solder pad 5, a vertical solder pad 6, a ground plane 7, a feed cable 8, a balun wire 9, an RF connector 10, a circular polarizer 11, and an impedance matching device 12. (See attached diagram) Figure 1 and Figure 2 .

[0023] The upper radiator 1 comprises four triangular aluminum plates of the same size, and the lower radiator 2 comprises four trapezoidal aluminum plates of the same size. A gap separates the upper radiator 1 and the lower radiator 2. The nylon support 3 is a hollow hemispherical structure, used to stably support the upper radiator 1, the lower radiator 2, and other structures. Short-circuit pins 4 connect the lower radiator to the ground plane 7, and are evenly distributed around the ground plane 7, with a total of eight pins. There is one horizontal solder pad 6 and one vertical solder pad 7, used to feed power to the two pairs of orthogonally polarized upper radiators 1. One end of the solder pad is welded to the upper radiator 1, and the other end is welded to the inner conductor of the feed cable 8.

[0024] There are two RF connectors 10. The horizontal solder pad 6 and the vertical solder pad 7 are each connected to the RF connector 10 through a power supply cable 8 of equal length. The two RF connectors 10 are each connected to the two inputs of the impedance matching device 12 through an RF line of equal length. The output of the impedance matching device 12 is connected to the two inputs of the circular polarizer 11 through two RF lines of equal length.

[0025] Impedance matching unit 12 includes: matching unit housing 13, impedance matching circuit 14, and RF connector 15, see Figure 3 The matching unit housing 13 is used to integrate the internal components together. The impedance matching circuit 14 consists of two identical printed circuit boards mounted side by side inside the matching unit housing 13. The impedance matching circuit 14 is a double-sided PCB board with inductors, capacitors and other components soldered on it. The RF connector 15 has a total of 4 SMA connectors, 2 for input and 2 for output.

[0026] The impedance matching circuit 14 is a double-sided PCB circuit, comprising: a microstrip network 16, a dielectric substrate 17, an inductor ① 18, a capacitor ① 19, an open-circuit slot 20, a capacitor ② 21, a capacitor ① 22, an inductor ② 23, and a grounding via 24. (See attached image) Figure 4 .

[0027] To illustrate the structure and features of the present invention in detail, the technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0028] See Figure 1 and Figure 2 , Figure 1 This is a perspective view of a grounded miniaturized oscillator circularly polarized antenna structure according to the present invention. Figure 2This is a side view. In this embodiment, the upper radiator 1 consists of four triangular pieces with a certain curvature, attached to the nylon support 3. The lower radiator 2 also consists of four trapezoidal pieces with a certain curvature, attached to the nylon support 3. The upper radiator 1 is made of aluminum, with an arc length of 72mm and an arc angle of 78.2°. The lower radiator 2 is also made of aluminum, with a vertical side length of 98.7mm, a top side length of 93.7mm, a bottom side length of 126.2mm, and an arc angle of 65°. A 12.8mm gap separates the upper and lower radiators 1 and 2. The nylon support 3 is a hollow hemispherical structure made of nylon, with a thickness of 7mm, a diameter of 220mm, and a height of 130mm. Eight shorting pins 4, made of stainless steel, are used to short-circuit each lower radiator 2 to the grounding plate 7. The horizontal welding piece 5 and the vertical welding piece 6 are made of copper, which facilitates welding connection. The dimensions of the horizontal welding piece 5 and the vertical welding piece 6 are 47mm in length, 7mm in width, and 0.5mm in thickness. The horizontal welding piece 5 and the vertical welding piece 6 are isolated and insulated from each other by a rubber sleeve.

[0029] In this embodiment, there are two feed cables 8, extending downwards from one end of the horizontal solder pad 5 and the vertical solder pad 6 respectively to the ground plane 7, and fixed to the ground plane 7 by the RF connector 10. The feed cables 8 are 136mm long. The inner cores of the two feed cables 8 are connected to the horizontal solder pad 5 and the vertical solder pad 6 by welding. After the outer shielding layer of the two feed cables 8 is removed, it is connected to the two upper radiators 1 by welding. The other ends of the horizontal solder pad 5 and the vertical solder pad 6 are connected to the upper radiators 1 by welding. The feed balun 9 is a 130mm long copper wire. One feed balun 9 is connected side-by-side to each feed cable 8. The middle part of the feed balun 9 is wrapped with a rubber sleeve, with only 5mm of copper wire exposed at both ends. The exposed copper wire at the upper end is soldered to the inner core of the feed cable 8, and the exposed copper wire at the lower end is soldered to the shielding layer of the feed cable 8 near the ground plane 7. The feed balun 9 forms a 1 / 4 wavelength choke structure, which can suppress unfavorable currents on the outer shielding layer of the feed cable 8 and improve the radiation pattern. The impedance matching circuit 12 is a four-port network, measuring 55mm × 25mm. Two inlets are connected to two RF connectors 10, and two outlets are connected to the two inlets of the circular polarizer 11. The circular polarizer 11 is a four-port network used to phase-shift and synthesize two orthogonally polarized linearly polarized waves entering from the inlets, outputting a circularly polarized wave at the outlet.

[0030] In this embodiment, the impedance matching device 12 includes: 13, a matching device housing, 14, an impedance matching circuit, and an RF connector 15, see below. Figure 3The matching housing 13 is used to integrate the internal components and measures 120mm × 67mm × 42.5mm. The impedance matching circuit 14 consists of two identical printed circuit boards, each measuring 25mm × 55mm, mounted side-by-side inside the matching housing 13.

[0031] In this embodiment, the impedance matching circuit is a double-sided PCB board. The printed circuit board is made of polytetrafluoroethylene (PTFE) board with a dielectric constant of 2.2 and a substrate thickness of 1.106 mm. The front side of the printed circuit board is a microstrip network 16, and the back side is a complete copper ground. The back side is in close contact with the inner surface of the matching circuit housing to ensure good heat dissipation. The linewidth of the microstrip network 16 is 3 mm, corresponding to a transmission line impedance of 50 ohms. Inductor ① is a 1206 packaged surface-mount inductor with a certain current withstand capability and an inductance value of 33 nH. Inductor ② is a 1206 packaged surface-mount inductor with a certain current withstand capability and an inductance value of 39 nH. Capacitor ① is a 1206 packaged surface-mount capacitor with a certain voltage withstand capability and a capacitance value of 6.8 pF. Capacitor ② is a 1206 packaged surface-mount capacitor with a certain voltage withstand capability and a capacitance value of 13 pF. There are 20 grounding metallized vias with a diameter of 0.5 mm. In the matching circuit, inductor ① is connected in parallel to reduce the inductive reactance in the complex impedance. The first capacitor ①19, the second capacitor ①22, and the inductor ②23 are connected together to form an "L"-shaped network, forming a low-pass filter. The capacitor ②21 is connected in series to reduce the capacitive reactance in the complex impedance, and finally the complex impedance is reduced to a pure real part of 50 ohms.

[0032] In this embodiment, the Figure 5 The voltage standing wave ratio (VSWR) curve for this embodiment of the invention has a lower boundary of 330MHz and a relative bandwidth of 37%. The VSWR is the optimal result after optimization design. It can be optimized by adjusting the width of the upper radiator 1 and the size of the gap between the upper radiator 1 and the lower radiator 2. Alternatively, the VSWR can also be optimized by adjusting the component values ​​on the impedance matching circuit.

[0033] In this embodiment, Figure 6 and Figure 7 The simulated gain pattern of this embodiment of the invention shows that the antenna gain is 4.0 dBi, which is greater than 4.0 dBi, indicating good directional radiation characteristics. The front-to-back ratio is over 20 dB, and... and Gain direction on two cross-sections Figure 1 With good consistency and beam equalization, this antenna has high engineering application value. The antenna of this invention incorporates power handling design in terms of material and component selection, as well as structure, enabling it to withstand power levels exceeding 50W, thus broadening the antenna's applicability across various scenarios.

[0034] In this embodiment, Figure 8 and Figure 9 The figure shows the circular polarization axial ratio curve of an embodiment of the present invention. As can be seen from the figure, the axial ratios of both left-hand and right-hand circular polarization of the antenna are less than 2.0 dB, indicating that the antenna has good circular polarization radiation characteristics.

[0035] The above description is merely a preferred embodiment of the present invention, intended to further illustrate the invention, and not to limit it. Any simple substitutions made based on the content disclosed in the above text and drawings are within the scope of protection of this patent.

Claims

1. A grounded miniaturized circularly polarized satellite communication antenna, comprising an upper radiator (1), a lower radiator (2), and a nylon support (3); characterized in that, The upper radiator (1) and the lower radiator are both covered on the outer surface of the nylon support (3); The nylon support (3) is a hollow hemispherical structure, and the upper radiator (1) covers the top of the hollow hemispherical structure. It consists of four upper radiating patches; the four upper radiating patches are arranged in a circular array, and the upper radiating patches facing each other are connected by corresponding solder pads. The lower radiator (2) consists of four lower radiating patches, which correspond one-to-one with the four upper radiating patches. The lower radiating patches are located below the corresponding upper radiating patches. The bottom edge of the lower radiating patch is attached to the bottom edge of the hollow hemispherical structure. There is a gap between the top edge of the lower radiating patch and the bottom edge of the upper radiating patch. The bottom of the nylon support (3) is provided with a grounding plate (7), and the lower radiator is short-circuited to the grounding plate (7) through a short-circuit pin (4); Each solder pad is connected to the corresponding RF connector (10) via the corresponding feed cable (8); the RF connector (10) is connected to the circular polarizer (11) via the impedance matching device (12).

2. The grounded miniaturized oscillator circularly polarized satellite communication antenna according to claim 1, characterized in that, The upper radiating patch is a triangular aluminum plate, and the lower radiating patch is a trapezoidal aluminum plate.

3. A grounded miniaturized circularly polarized satellite communication antenna according to claim 1, characterized in that, Each radiation patch is connected to the grounding plate (7) via two shorting pins (4).

4. A grounded miniaturized circularly polarized satellite communication antenna according to claim 1, characterized in that, There are gaps between adjacent radiating patches.

5. A grounded miniaturized circularly polarized satellite communication antenna according to claim 1, characterized in that, Two solder pads are used to feed two pairs of orthogonally polarized upper radiators (1). One end of the solder pad is soldered to the corresponding upper radiator patch, and the other end is soldered to the inner conductor of the feed cable (8).

6. A grounded miniaturized circularly polarized satellite communication antenna according to claim 1, characterized in that, There are two RF connectors (10), two feed cables (8) of equal length, and two solder pads are connected to the corresponding RF connectors (10) through one feed cable (8) of equal length. The two RF connectors (10) are each connected to the two inputs of the impedance matching device (12) through one RF line of equal length. The output of the impedance matching device (12) is connected to the two inputs of the circular polarizer (11) through two RF lines of equal length.

7. A grounded miniaturized circularly polarized satellite communication antenna according to claim 1, characterized in that, The impedance matching device (12) includes a matching device housing (13), an impedance matching circuit (14), and an RF connector X (15); the impedance matching circuit (14) and the RF connector X (15) are both located inside the matching device housing (13); The impedance matching circuit (14) has two circuits, both of which are double-sided PCB circuits. The main body of the double-sided PCB circuit is a dielectric substrate (17). A microstrip network (16) is etched on the dielectric substrate (17). The four SMA connectors of the RF connector X (15) are connected to the microstrip network, two of which are inputs and the other two are outputs.

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