Satellite antenna structure and use method thereof

Abstract

The invention provides a satellite antenna structure and a use method thereof, and belongs to the technical field of communication antennas. Comprising a satellite antenna, a satellite PCB, a frequency selection-PCB, an antenna connector and a coaxial line. The antenna connector is a standard SMA-K / SMA-J thread, one end of the antenna connector is used for accessing an external signal, and the other end of the antenna connector is welded with the frequency selection-PCB; the frequency selection-PCB is provided with a signal input point, an RTK signal input point, a DMR signal input point and a ground bonding pad, the signal input point is welded with a feeding point of the antenna connector, and the ground bonding pad is welded with a grounding end of the antenna connector; the coaxial line comprises an outer braid layer, an insulating layer and an inner conductor, the outer braid layer at the right end of the coaxial line is welded on a bonding pad corresponding to a DMR signal input point of the frequency selection-PCB, and the inner conductor at the right end of the coaxial line is welded on a bonding pad corresponding to an RTK signal input point of the frequency selection-PCB. According to the invention, the problems of large size, serious interference, poor compatibility and incomplete frequency band coverage caused by multi-antenna separation in the prior art are solved, and the integration of satellite communication, DMR communication and selectable 4G communication is realized.

Description

Technical Field

[0001] This invention provides a satellite antenna structure and its usage method, belonging to the field of communication antenna technology. Background Technology

[0002] In emergency communications and outdoor duty scenarios, equipment often needs to simultaneously possess satellite communication (such as RTK positioning and Tiantong satellite communication) and DMR short-range communication capabilities, and in some scenarios, it also needs to be compatible with 4G public network communication. In existing technologies, satellite antennas and DMR antennas are mostly designed independently, which has the following drawbacks:

[0003] The separate setup of multiple antennas results in large, unsightly, and cumbersome equipment, and poor flexibility when adapting to portable equipment such as duty aircraft.

[0004] Signal interference can easily occur between different antennas, especially when the frequency bands of DMR signals and satellite signals are close, the interference problem is prominent and affects the stability of communication.

[0005] The antenna interfaces are not standardized, resulting in insufficient compatibility when adapting to different devices. Furthermore, the traditional antenna structure is not bendable and has poor structural strength.

[0006] Existing integrated antennas often suffer from impedance mismatch and incomplete frequency band coverage, making it difficult to simultaneously meet the transmission requirements of satellite signals (such as 1176-1227MHz, 1980-2010MHz, etc.) and DMR signals (136-174MHz, 320-520MHz).

[0007] Therefore, in view of this, we studied and improved the existing structure, and proposed a satellite antenna structure and its usage method to solve the above-mentioned problems. Summary of the Invention

[0008] The purpose of this invention is to overcome the defects of the prior art and provide a satellite antenna structure that solves the problems of large size, serious interference, poor compatibility and incomplete frequency band coverage caused by the existing multi-antenna discrete structure, and realizes the integrated integration of satellite communication, DMR communication and optional 4G communication.

[0009] To address the aforementioned problems, the present invention proposes the following technical solution: a satellite antenna structure, comprising a satellite antenna, a satellite PCB board, a frequency-selective PCB, an antenna connector, and a coaxial cable; the antenna connector is a standard SMA-K / SMA-J thread, with one end used to receive external signals and the other end soldered to the frequency-selective PCB; the frequency-selective PCB is provided with a signal input point, an RTK signal input point, a DMR signal input point, and a ground pad, the signal input point being soldered to the antenna connector feed point, and the ground pad being soldered to the antenna connector grounding terminal; the coaxial cable comprises an outer braided layer, an insulating layer, and an inner conductor, the outer braided layer at the right end of the coaxial cable being soldered to the frequency-selective PCB... On the pads corresponding to the DMR signal input points of the PCB, the inner conductor at the right end of the coaxial cable is soldered to the pads corresponding to the RTK signal input points of the frequency-selective PCB. The outer braided layer at the left end of the coaxial cable is soldered to the ground pad of the satellite PCB, and the inner conductor at the left end of the coaxial cable is soldered to the signal transmission line pads of the satellite PCB. The satellite PCB is a passive circuit design, and impedance and frequency are adjusted in conjunction with the transmission line impedance of the satellite antenna. The satellite PCB and the satellite antenna together constitute the satellite signal radiator. The outer braided layer of the coaxial cable, the ground of the satellite PCB, and the specific frequency stubs of the satellite antenna are connected as one to form the DMR antenna radiator.

[0010] Furthermore, the frequency selection PCB is equipped with a bandpass circuit, an impedance matching circuit, and a bandstop circuit. The bandpass circuit consists of capacitor C3, inductor L3, capacitor C4, and inductor L4, and is used to filter DMR signals in the 136-174MHz and 320-520MHz frequency bands. The impedance matching circuit consists of capacitor C1 and inductor L1 forming an L-shaped structure, and is used to match the transmission line impedance from the signal input point to the DMR signal input point to 50 ohms. The bandstop circuit consists of inductor L2 and capacitor C2, and is used to block DMR signals in the 136-174MHz and 320-520MHz frequency bands to avoid crosstalk to satellite signals.

[0011] Furthermore, the satellite antenna is an RTK antenna, the satellite PCB board is a passive RTK-PCB board, the satellite antenna radiator is a four-walled spiral design, and the operating frequency range of the satellite antenna is 1556-1601MHz and 1176-1227MHz; the linear length of the DMR antenna radiator conforms to a quarter wavelength corresponding to the frequency of 136-174MHz or 320-520MHz, and full coverage of the 136-174MHz or 320-520MHz frequency band can be achieved by changing the length of the coaxial cable.

[0012] Furthermore, the satellite antenna is a Tiantong satellite antenna, the satellite PCB board is a Tiantong PCB board, and the operating frequency range of the Tiantong satellite signal is 1980-2010MHz and 2170-2200MHz; the DMR antenna radiator is composed of an outer braided layer of a coaxial line and the ground of the Tiantong PCB board. By adjusting the length of the coaxial line, the line length of the radiator is made to meet the quarter wavelength corresponding to the DMR operating frequency.

[0013] Furthermore, the insulation layer of the coaxial cable is designed with a 50-ohm impedance for satellite transmission lines to achieve isolation between the outer braided layer and the inner conductor of the coaxial cable.

[0014] Furthermore, the satellite antenna structure is also compatible with 4G communication modules, forming an integrated satellite + DMR + 4G antenna structure, and it uses the same coaxial cable outer braided layer as the DMR antenna radiator design.

[0015] Furthermore, the area where the coaxial cable is located is designed as a bendable structure, and the antenna connector and the outer injection molding size are adapted to the standard interface size of duty aircraft on the market.

[0016] Furthermore, this includes the following steps:

[0017] Step 1: Connect the external satellite signal and DMR signal to the signal input point of the frequency selection PCB through the antenna connector;

[0018] Step 2: Frequency selection - The bandpass circuit on the PCB filters out the DMR signal. After the impedance matching circuit completes 50 ohms impedance matching, the DMR signal is transmitted to the DMR signal input point. The coaxial cable outer braid layer, RTK-PCB board, and the line's FPC serve as DMR antenna radiators for signal radiation.

[0019] Step 3: Frequency selection - The band-stop circuit on the PCB blocks the DMR signal, allowing the satellite signal to be transmitted through the RTK signal input point to the inner conductor of the coaxial cable, and then to the satellite PCB board. The satellite signal radiator, composed of the satellite PCB board and the satellite antenna, radiates the satellite signal.

[0020] Step 4: Change the satellite antenna and satellite PCB board type according to actual needs, adjust the coaxial cable length, and adapt to the usage requirements of different satellite signal frequency bands and DMR signal frequency bands.

[0021] Due to the adoption of the above technical solution, the beneficial effects of the satellite antenna structure and its usage method of the present invention are as follows:

[0022] 1. Integrated design: The satellite antenna, DMR antenna and optional 4G antenna are integrated into one unit, which greatly reduces the size of the equipment, simplifies the installation process, and is suitable for use scenarios of portable equipment such as duty aircraft;

[0023] 2. Strong anti-interference capability: The bandpass and bandstop circuits on the frequency selection PCB are used to filter DMR signals and block DMR interference to satellite signals. At the same time, the satellite PCB adopts a passive circuit design and combines transmission line impedance adjustment to ensure independent and stable transmission of each signal frequency band.

[0024] 3. Comprehensive frequency band coverage: By changing the satellite antenna type (RTK / Tiantong), it can be adapted to satellite frequency bands such as 1176-1227MHz, 1556-1601MHz, 1980-2010MHz, and 2170-2200MHz. Adjusting the coaxial cable length can achieve full coverage of the 136-174MHz and 320-520MHz DMR frequency bands. After being compatible with 4G communication modules, it can further expand application scenarios.

[0025] 4. Excellent compatibility and portability: The antenna connector adopts standard SMA-K / SMA-J threads, and the injection-molded size is compatible with standard interfaces on the market. The coaxial cable is designed with a bendable structure to improve the flexibility of use.

[0026] 5. Precise impedance matching: The coaxial cable insulation layer is designed for 50-ohm impedance, and the L-shaped impedance matching circuit on the frequency-selective PCB ensures impedance matching for DMR signal transmission, reducing signal attenuation. Attached Figure Description

[0027] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0028] Figure 1 This is a schematic diagram of a satellite antenna structure and its usage method according to the present invention.

[0029] Figure 2 This is a schematic diagram of the internal structure of a satellite antenna structure and its usage method according to the present invention.

[0030] Figure 3 This is a partial structural diagram of a satellite antenna structure and its usage method according to the present invention. Figure 1 .

[0031] Figure 4 This is a partial structural diagram of a satellite antenna structure and its usage method according to the present invention. Figure 2 .

[0032] In the picture:

[0033] 1. RTK antenna; 2. RTK-PCB board; 3. Coaxial cable outer braided layer; 4. Coaxial cable inner conductor; 5. DMR signal input point; 6. RTK signal input point; 7. Frequency selective PCB; 8. Signal input point. Detailed Implementation

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Example 1: Integrated RTK+DMR Antenna Structure

[0036] In this embodiment, an RTK antenna is selected for the satellite antenna, and the satellite PCB board is an RTK-PCB board with the following specific parameters: Satellite signal operating frequency: 1176-1227MHz, 1556-1601MHz; RTK antenna specific frequency stub: 1156-1601MHz stub; DMR signal operating frequency band: 136-174MHz; Coaxial cable length: designed as 68-72cm according to the quarter wavelength corresponding to the 136-174MHz frequency band; Frequency selection-PCB parameters: Capacitor C1 = 10pF, Inductor L1 = 10nH; Capacitor C3 = 22pF, Inductor L3 = 8nH, Capacitor C4 = 22pF, Inductor L4 = 8nH; Inductor L2 = 15nH, Capacitor C2 = 15pF; Coaxial cable specifications: Insulation layer thickness 1.2mm, outer braided layer is made of tin-plated copper wire braid, inner conductor is a copper core with a diameter of 0.8mm, ensuring 50-ohm impedance matching.

[0037] Assembly process

[0038] The RTK antenna is fixedly connected to the RTK-PCB board, ensuring impedance matching of the satellite signal radiators formed by the two. The signal input point of the frequency-selective PCB is soldered to the feed point of the standard SMA-K antenna connector, and the ground pad is soldered to the ground terminal of the antenna connector. The outer braided layer of the right end of the coaxial cable is soldered to the DMR signal input pad of the frequency-selective PCB, and the inner conductor of the right end is soldered to the RTK signal input pad. The outer braided layer of the left end of the coaxial cable is soldered to the ground pad of the RTK-PCB board, and the inner conductor of the left end is soldered to the signal transmission line pad of the RTK-PCB board. The antenna connector and the coaxial cable connection are injection molded to ensure that the coaxial cable can be bent at an angle ≥90° and the package size is compatible with the SMA interface of commercially available duty aircraft.

[0039] Usage process

[0040] External satellite signals and 136-174MHz DMR signals are input to the signal input point of the frequency selection PCB through an SMA-K connector. The bandpass circuit filters out the 136-174MHz DMR signals, which are then adjusted to 50 ohms by the C1-L1 impedance matching circuit and transmitted to the outer braided layer of the coaxial cable through the DMR signal input point. The DMR radiator, composed of the outer braided layer, the ground of the RTK-PCB board, and the 1156-1601MHz stub of the RTK antenna, radiates the signals. The bandstop circuit blocks the 136-174MHz signals. The satellite signals are transmitted to the inner conductor of the coaxial cable through the RTK signal input point and then to the RTK-PCB board. The satellite radiator, composed of the RTK-PCB board and the RTK antenna, radiates 1176-1227MHz and 1556-1601MHz signals.

[0041] Example 2: Integrated antenna structure of Tiantong + DMR + 4G

[0042] In this embodiment, the satellite antenna is a Tiantong satellite antenna, and the satellite PCB board is a Tiantong PCB board. A new 4G communication module is added, with the following specific parameters: Tiantong satellite signal operating frequency: 1980-2010MHz, 2170-2200MHz; DMR signal operating frequency band: 320-520MHz; 4G communication frequency band: 900MHz, 1800MHz, 2600MHz; coaxial line length: designed as 14-23cm based on a quarter wavelength of 320-520MHz; frequency selection-PCB parameters: capacitor C1 = 8pF, inductor L1 = 12nH; capacitor C3 = 18pF, inductor L3 = 6nH; capacitor C4 = 18pF, inductor L4 = 6nH; inductor L2 = 12nH, capacitor C2 = 18pF; the 4G antenna vibrator is soldered to the reserved pads on the Tiantong PCB board and isolated from the outer braided layer of the coaxial line through the ground of the Tiantong PCB board, allowing for independent signal radiation.

[0043] The assembly and usage process of this embodiment is the same as that of embodiment 1. The difference is that the DMR radiator is composed of an outer braided layer of the coaxial cable and the ground of the Tiantong PCB board. The 4G antenna is integrated through a reserved solder pad, which does not affect the transmission of satellite and DMR signals, and realizes three-mode communication of satellite + DMR + 4G.

[0044] Example 3: Frequency band adaptation adjustment of antenna structure

[0045] When switching the DMR band from 136-174MHz to 320-520MHz, simply adjust the coaxial cable length from 68-72cm to 14-23cm; no other components need to be replaced. When changing the satellite antenna from RTK to Tiantong, simply replace the RTK antenna and RTK-PCB board with the Tiantong satellite antenna and Tiantong PCB board, keeping the frequency selection-PCB, coaxial cable, and antenna connector unchanged. This completes the frequency band adaptation, making the operation simple.

[0046] It should be noted that the above embodiments are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any obvious modifications, substitutions or alterations without departing from the concept of the present invention should fall within the protection scope of the present invention.

[0047] The present invention and its embodiments have been described above. This description is not restrictive. In short, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of the present invention, such design should fall within the protection scope of the present invention.

Claims

1. A satellite antenna structure, characterized in that, The system includes a satellite antenna, a satellite PCB, a frequency-selective PCB (7), an antenna connector, and a coaxial cable. The antenna connector is a standard SMA-K / SMA-J threaded connector, with one end used to connect to an external signal and the other end soldered to the frequency-selective PCB (7). The frequency-selective PCB (7) is provided with a signal input point (8), an RTK signal input point (8)(6), a DMR signal input point (5), and a ground pad. The signal input point (8) is soldered to the antenna connector feed point, and the ground pad is soldered to the antenna connector grounding terminal. The coaxial cable includes an outer braided layer, an insulating layer, and an inner conductor. The outer braided layer at the right end of the coaxial cable is soldered to the DMR signal input point of the frequency-selective PCB (7). On the pad corresponding to input point (5), the inner conductor at the right end of the coaxial line is soldered to the pad corresponding to the RTK signal input points (8) and (6) of the frequency selection PCB (7). The outer braided layer at the left end of the coaxial line is soldered to the ground pad of the satellite PCB board, and the inner conductor at the left end of the coaxial line is soldered to the signal transmission line pad of the satellite PCB board. The satellite PCB board is a passive circuit design, and the impedance and frequency are adjusted by combining the transmission line impedance with the satellite antenna. The satellite PCB board and the satellite antenna together constitute the satellite signal radiator. The outer braided layer of the coaxial line, the ground of the satellite PCB board, and the specific frequency stub of the satellite antenna are connected together to form the DMR antenna radiator.

2. The satellite antenna structure according to claim 1, characterized in that, The frequency selection PCB (7) is provided with a bandpass circuit, an impedance matching circuit and a bandstop circuit; the bandpass circuit is composed of capacitor C3, inductor L3, capacitor C4 and inductor L4, and is used to filter DMR signals in the 136-174MHz and 320-520MHz frequency bands; the impedance matching circuit is composed of capacitor C1 and inductor L1 in an L-shaped structure, and is used to match the impedance of the transmission line from the signal input point (8) to the DMR signal input point (5) to 50 ohms; the bandstop circuit is composed of inductor L2 and capacitor C2, and is used to block DMR signals in the 136-174MHz and 320-520MHz frequency bands to avoid interference with satellite signals.

3. A satellite antenna structure according to claim 1, characterized in that, The satellite antenna is an RTK antenna (1), the satellite PCB board is a passive RTK-PCB board (2), the satellite antenna radiator is a four-walled spiral design, and the operating frequency range of the satellite antenna is 1556-1601MHz and 1176-1227MHz; the line length of the DMR antenna radiator conforms to a quarter wavelength corresponding to the frequency of 136-174MHz or 320-520MHz, and full coverage of the 136-174MHz or 320-520MHz frequency band can be achieved by changing the length of the coaxial line.

4. A satellite antenna structure according to claim 1, characterized in that, The satellite antenna is a Tiantong satellite antenna, and the satellite PCB board is a Tiantong PCB board. The operating frequency range of the Tiantong satellite signal is 1980-2010MHz and 2170-2200MHz. The DMR antenna radiator is composed of an outer braided layer of a coaxial line and the ground of the Tiantong PCB board. By adjusting the length of the coaxial line, the line length of the radiator is made to meet the quarter wavelength corresponding to the DMR operating frequency.

5. A satellite antenna structure according to claim 1, characterized in that, The insulation layer of the coaxial cable is designed with a 50-ohm impedance for satellite transmission lines to achieve isolation between the outer braided layer (3) and the inner conductor of the coaxial cable.

6. A satellite antenna structure according to claim 1, characterized in that, The satellite antenna structure is also compatible with 4G communication modules, forming a satellite + DMR + 4G integrated antenna structure, and uses the coaxial outer braided layer (3) as the DMR antenna radiator design.

7. A satellite antenna structure according to claim 1, characterized in that, The area where the coaxial cable is located is designed as a bendable structure, and the antenna connector and the outer injection molding size are adapted to the standard interface size of duty aircraft on the market.

8. A method of using a satellite antenna structure according to claim 1, comprising the following steps: Step 1: Connect the external satellite signal and DMR signal to the signal input point (8) of the frequency-selective PCB (7) through the antenna connector; Step 2: Frequency selection - The bandpass circuit on the PCB (7) filters out the DMR signal. After the impedance matching circuit completes 50 ohms impedance matching, the DMR signal is transmitted to the DMR signal input point (5). The coaxial cable outer braided layer (3), RTK-PCB board (2), and the line LPC serve as DMR antenna radiators for signal radiation. Step 3: Frequency selection - The band-stop circuit on the PCB (7) blocks the DMR signal, so that the satellite signal is transmitted to the inner conductor (4) of the coaxial line through the RTK signal input point (8)(6), and then transmitted to the satellite PCB board. The satellite signal radiator composed of the satellite PCB board and the satellite antenna radiates the satellite signal. Step 4: Change the satellite antenna and satellite PCB board type according to actual needs, adjust the coaxial cable length, and adapt to the usage requirements of different satellite signal frequency bands and DMR signal frequency bands.

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