A vehicle-mounted anti-interference shell conformal positioning antenna

Abstract

The utility model discloses a kind of vehicle-mounted anti-interference shell conformal positioning antennas, including antenna body and feed circuit;Wherein, antenna body includes PCB board, even number L-shaped antenna metal array, metal piece with opening and antenna cover shell, L-shaped antenna metal array and feed circuit are set on PCB board, L-shaped antenna metal array is set metal piece with opening above, antenna cover shell is set above metal piece with opening;L-shaped antenna metal array is set corresponding with upper hole one by one, one L-shaped antenna metal array and the hole above it form a circular polarized antenna.The antenna diameter can be achieved within 100mm, height within 30mm, can be installed below car glass sunroof or inside rear spoiler. Realize vehicle batch installation. L-shaped metal array and round hole are all irrelevant with antenna 1 / 4, so same frequency interference signal cannot interfere with the normal work of antenna. Solve current car complex EMC environment, positioning antenna interference problem, passive gain maximum >7dBi above.

Description

Technical Field

[0001] This utility model belongs to the field of antennas, specifically relating to a vehicle-mounted anti-interference shell conformal positioning antenna. Background Technology

[0002] Currently, the anti-interference antenna is a null-adjustment antenna solution, such as... Figure 1 , Figure 2 As shown, it mainly consists of three parts: a main receiving antenna 6, an array antenna 7, and an integrated circuit board 8. The integrated circuit board contains a processor. Using an adaptive algorithm, it first determines the direction and strength of the interference signal by collecting data from the surrounding array antennas. Then, through calculation, it shapes the main antenna beamwidth, creating a null pattern in the direction of the interference, thus reducing the reception of the interference signal. This reduces the reception of interference signals. Existing anti-interference antennas have the following characteristics:

[0003] 1. The existing antenna is too large to be mass-produced and installed in a typical vehicle environment. This is because there are array antennas nearby, and a certain distance needs to be maintained between them and the main antenna.

[0004] 2. Existing antennas are expensive, costing several thousand or even over ten thousand yuan, making mass vehicle-mount installation difficult. This is because complex algorithms are needed to control antenna beamforming, requiring the integration board to house MCUs, memory, digital-to-analog converters, phase controllers, and other complex hardware designs.

[0005] 3. Existing antennas are generally used in military applications such as weaponry, where interference sources are typically far away or have a relatively fixed direction. However, in actual vehicle environments, antennas may be closer to interference sources, and the types of interference are more diverse. Examples include interference from car infotainment systems, dashcams in rearview mirrors, roof-mounted LiDAR, and high-speed data cables and high-power power cables within wiring harnesses. Interference types include narrowband interference at the same frequency and high-power, oppressive interference. Given the confined space inside a vehicle, antennas are generally surrounded by various interference sources from multiple directions, not just a single one, making it impossible to achieve a null antenna pattern.

[0006] 4. As long as the interference frequency is close to 1 / 4 wavelength and the size of the antenna array, the interference signal will be received and amplified, causing interference suppression failure. This is because interference signals in the environment can easily be transmitted from the top of the antenna, bypassing the surrounding array antennas and directly to the central main antenna. Summary of the Invention

[0007] The technical problem to be solved by this utility model is to provide a vehicle-mounted anti-interference shell conformal positioning antenna, which solves the problems of vehicle-mounted antenna size and anti-interference in the prior art.

[0008] To solve the above-mentioned technical problems, this utility model adopts the following technical solution:

[0009] A vehicle-mounted anti-interference conformal positioning antenna includes an antenna body and a feeding circuit. The antenna body includes a PCB board, an even number of L-shaped antenna metal elements, a metal part with openings, and an antenna cover. The L-shaped antenna metal elements and the feeding circuit are disposed on the PCB board. The metal part with openings is disposed above the L-shaped antenna metal elements, and the antenna cover is disposed above the metal part with openings. The L-shaped antenna metal elements are arranged in a one-to-one correspondence with the openings above them, and one L-shaped antenna metal element and the opening above it form a circularly polarized antenna.

[0010] The circularly polarized antennas are arranged in a rotationally symmetrical manner to form an array antenna.

[0011] The circularly polarized antenna comprises four L-shaped metal arrays arranged in a rotating manner in the same direction.

[0012] The feeding circuit is a 4-in-1 bridge feed, which makes the phase difference between the four circularly polarized antenna elements 90°.

[0013] The perforated metal part is formed by directly drilling holes in a sheet metal cover, printing a metal layer inside the cover, or injection molding a metal part into a mold.

[0014] The perforated metal part is the same shape as the antenna housing and is embedded inside the antenna housing.

[0015] The L-shaped antenna metal array uses a dielectric material with a high dielectric constant, and the metal is formed by printing or laser engraving on the dielectric material.

[0016] The length of the L-shaped antenna metal array is not equal to 1 / 4 wavelength of the operating frequency.

[0017] The PCB board, the metal part with openings, and the antenna housing are a matching circular structure.

[0018] By adjusting the relative positions of the L-shaped antenna metal elements and the openings, the antenna can operate at GNSS frequencies L1, B1, and G1, or the Tiantong satellite frequency range of 1980-2200MHz, while simultaneously covering Tiantong uplink and downlink frequencies.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The reduced size allows for mass production and installation in ordinary passenger vehicles. With an antenna diameter of less than 100mm and a height of less than 15mm, this invention can be installed below the sunroof or inside the rear spoiler of a car, enabling mass installation on various vehicles.

[0021] 2. The antenna of this utility model is mainly made of sheet metal and plastic, which is low in cost and easy to process. The sheet metal parts and the antenna housing are designed in a conformal manner, simplifying the installation process and saving costs. Four circularly polarized antennas form an array structure to improve gain.

[0022] 3. The L-shaped metal array and the circular hole are unrelated to the antenna's 1 / 4 wavelength, so co-channel interference signals cannot interfere with the antenna's normal operation. The downward-extending side enclosure of the sheet metal part and the PCB form a shielding structure, preventing the internal L-shaped metal array from directly contacting other high-power interference signals, thus resisting high-power interference signals. This invention addresses the interference problem of positioning antennas in the complex EMC environment of automobiles. The exposed portion of the antenna element is disproportionate to the signal's 1 / 4 wavelength, preventing interference signals from reaching the circuit.

[0023] 4. Improve antenna performance: Each L-shaped metal element and a circular aperture form a circularly polarized antenna. By arraying four circularly polarized antennas to form an array, the gain is improved. The maximum passive gain is >7dBi.

[0024] 5. It reduces costs and increases efficiency, enhances product competitiveness, and can be made into a standard, universally beneficial product that can be promoted and applied within the field, thus possessing significant market promotion value. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an antenna element structure in the prior art.

[0026] Figure 2 This is a schematic diagram of a multibeamforming structure in the prior art.

[0027] Figure 3 This is a schematic diagram of the antenna structure of this utility model.

[0028] Figure 4 This is the circuit diagram of the antenna feeding part of this utility model.

[0029] Figure 5 The waveform diagram of the return loss of antenna S11 of this utility model is shown.

[0030] Figure 6 This is a waveform diagram of the passive gain of the antenna of this utility model.

[0031] Figure 7 This is a schematic diagram of the antenna axis ratio of this utility model.

[0032] Figure 8 This is the 3D radiation pattern of the antenna of this utility model.

[0033] The labels in the diagram are as follows: 1-antenna housing; 2-metal part with opening; 3-PCB board; 4-opening; 5-L-shaped antenna metal array; 6-main receiving antenna; 7-array antenna; 8-integrated circuit board. Detailed Implementation

[0034] The structure and working process of this utility model will be further described below with reference to the accompanying drawings.

[0035] A vehicle-mounted anti-interference conformal positioning antenna includes an antenna body and a feeding circuit. The antenna body includes a PCB board, an even number of L-shaped antenna metal elements, a metal part with openings, and an antenna cover. The L-shaped antenna metal elements and the feeding circuit are disposed on the PCB board. The metal part with openings is disposed above the L-shaped antenna metal elements, and the antenna cover is disposed above the metal part with openings. The L-shaped antenna metal elements are arranged in a one-to-one correspondence with the openings above them, and one L-shaped antenna metal element and the opening above it form a circularly polarized antenna.

[0036] Specific embodiments, such as Figures 3 to 8 As shown:

[0037] A vehicle-mounted anti-interference conformal positioning antenna includes an antenna body and a feeding circuit. The antenna body includes a PCB board 3, an even number of L-shaped antenna metal elements 5, a metal part 2 with openings, and an antenna cover 1. The L-shaped antenna metal elements 5 and the feeding circuit are disposed on the PCB board. The metal part 2 with openings is disposed above the L-shaped antenna metal elements, and the antenna cover is disposed above the metal part with openings. The L-shaped antenna metal elements are arranged in a one-to-one correspondence with the openings 4 above them. One L-shaped antenna metal element and the opening above it form a circularly polarized antenna.

[0038] The core principle of this scheme is the L-shaped antenna metal element 5, which generates two mutually orthogonal current directions. These current directions resonate with the opening 4 (circular hole) in the upper metal component 2, forming a circularly polarized antenna. Two orthogonal polarizations with a 90° phase difference constitute a circularly polarized antenna. The L-shaped antenna metal element 5, arranged with rotational symmetry, forms a 4-element array antenna, further improving antenna gain and allowing the bandwidth to cover the L1, B1, and G1 frequency points.

[0039] The perforated metal part 2 can be a sheet metal structure, embedded in the antenna housing 1. Alternatively, the perforated metal part 2 can be replaced by a coated metal layer. This forms a conformal antenna housing. The distance between the L-shaped antenna metal array 5 and the perforation 4 in the perforated metal part 2 is related to the resonant frequency. The distance between the L-shaped antenna metal array 5 and the PCB board 3 also affects the resonant frequency.

[0040] The length of the L-shaped antenna's metal array is not directly proportional to its resonant frequency. Therefore, the length of the L-shaped antenna's metal array is not equal to 1 / 4 wavelength of the operating frequency, and the radius or perimeter of the opening 4 is also unrelated to 1 / 4 wavelength of the operating frequency. Some co-frequency interference signals cannot enter the antenna through the array and the circular opening because the interference signal's 1 / 4 wavelength does not match the dimensions of the antenna array and the circular opening. The metal sheet metal structure, with side enclosures, forms a shielding structure with the PCB board 3, shielding the array internally. External interference signals or high-power signals cannot directly cover or couple to the antenna array, so high-power interference such as radar waves and cameras cannot affect the antenna.

[0041] The L-shaped metal elements are arranged with rotational symmetry to form a 4-element antenna, where each element is an independent circularly polarized antenna. This array configuration increases the antenna gain. The passive maximum gain exceeds 7 dBi. Figure 6 As shown. Other solutions in the prior art are generally planar structures, typically with four linearly polarized elements. A phase-shifting network is used to make each element 90° out of phase to achieve a circular polarization effect, with the gain generally only reaching about 5dBi.

[0042] The L-shaped antenna metal array 5 can be replaced with other media, such as PPO, ceramics, or alumina, to further reduce its size by utilizing its high dielectric constant. The L-shaped metal array can be printed or laser-engraved on other media materials to achieve the above functions.

[0043] This antenna can be made to be less than 100mm in size and less than 30mm in height, and can be installed under the sunroof or inside the rear spoiler, enabling mass installation on vehicles.

[0044] Figure 8 It can be seen that the antenna phase center is less than or equal to 2mm. Figure 7 It can be seen that the antenna axial ratio is less than 3dB.

[0045] The circuit section is fed by a 4-in-1 bridge, which makes the phase difference between the four adjacent antenna elements 90° to form a circularly polarized antenna array. The signal is then amplified by an LNA, filtered, amplified by an LNA again, and finally output as a GNSS signal.

[0046] This invention, by adjusting the relative positions of the L-shaped antenna metal element 5 and the circular aperture, can also achieve coverage of the Tiantong satellite frequency range of 1980-2200MHz, simultaneously covering both uplink and downlink frequencies. Therefore, this invention is not limited to implementing GNSS functionality.

[0047] Note: L1: GPS 1575.42MHz

[0048] B1: Beidou 1561.098MHz

[0049] G1: GLONASS 1602MHz,

[0050] LNA: Low Noise Amplifier.

[0051] The antenna disclosed in this solution can be applied to different products.

[0052] Typical Application: Applied to intelligent driver assistance systems in automobiles, this antenna is installed inside the rear spoiler of a car to receive positioning satellite signals. It simultaneously supports three frequency points: BeiDou B1, GPS L1, and GLONASS G1. The received signal is further amplified and filtered by a back-end amplification circuit before being input to the vehicle's positioning system. The vehicle system internally calculates position information, clock information, etc. The car uses this information to achieve driver assistance. The antenna dimensions are 80mm in diameter and 24mm in height. The phase center is less than or equal to 2mm, and the positioning accuracy error can reach the centimeter level.

[0053] It should be understood that this solution is not limited to the specific embodiments described above. Devices and structures not described in detail herein should be understood as being implemented in a manner common to the art. Any person skilled in the art can make many possible variations and modifications to this solution, or modify it into equivalent embodiments, without departing from the scope of this solution, using the methods and techniques disclosed above. This does not affect the substantive content of this solution. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this solution, without departing from its scope, still fall within the protection scope of this solution.

Claims

1. A vehicle-mounted anti-interference conformal positioning antenna, characterized in that: The antenna includes an antenna body and a feeding circuit. The antenna body includes a PCB board, an even number of L-shaped antenna metal elements, a metal part with openings, and an antenna housing. The L-shaped antenna metal elements and the feeding circuit are mounted on the PCB board. The metal part with openings is mounted above the L-shaped antenna metal elements, and the antenna housing is mounted above the metal part with openings. The L-shaped antenna metal elements are arranged in a one-to-one correspondence with the openings above them. One L-shaped antenna metal element and the opening above it form a circularly polarized antenna.

2. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 1, characterized in that: The circularly polarized antennas are arranged in a rotationally symmetrical manner to form an array antenna.

3. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 2, characterized in that: The circularly polarized antenna comprises four L-shaped metal arrays arranged in a rotating manner in the same direction.

4. The vehicle-mounted anti-interference housing conformal positioning antenna according to claim 3, characterized in that: The feeding circuit is a 4-in-1 bridge feed, which makes the phase difference between the four circularly polarized antenna elements 90°.

5. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 1, characterized in that: The perforated metal part is formed by directly drilling holes in a sheet metal cover, printing a metal layer inside the cover, or injection molding a metal part into a mold.

6. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 5, characterized in that: The perforated metal part is the same shape as the antenna housing and is embedded inside the antenna housing.

7. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 1, characterized in that: The L-shaped antenna metal array uses a dielectric material with a high dielectric constant, and the metal is formed by printing or laser engraving on the dielectric material.

8. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 1, characterized in that: The length of the L-shaped antenna metal array is not equal to 1 / 4 wavelength of the operating frequency.

9. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 1, characterized in that: The PCB board, the metal part with openings, and the antenna housing are a matching circular structure.

10. The vehicle-mounted anti-interference shell conformal positioning antenna according to claim 1, characterized in that: By adjusting the relative positions of the L-shaped antenna metal elements and the openings, the antenna can operate at GNSS frequencies L1, B1, and G1, or the Tiantong satellite frequency range of 1980-2200MHz, while simultaneously covering Tiantong uplink and downlink frequencies.

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