Cavity type high-precision GNSS antenna device

Abstract

The utility model discloses a cavity type high precision GNSS antenna device, relates to the positioning antenna technology field, and comprises an antenna unit, the antenna unit comprises a PPO plate, the PPO plate is lined with a first square microstrip patch, the first square microstrip patch is provided with a plurality of rectangular tuning teeth, and the rectangular tuning teeth are arranged on the PPO plate. The inner side of the PPO plate is symmetrically provided with a first feed point and a second feed point, the PPO plate is provided with a second square micro-strip patch, the second square micro-strip patch is provided with a cut corner corresponding to the PPO plate, the first square micro-strip patch is provided with a metalized via hole in a penetrating manner, and the metalized via hole penetrates through the second square micro-strip patch. The antenna radiator is designed by adopting a single-layer multi-feed mode, so that the miniaturization of the antenna is realized, the impedance bandwidth of the antenna is expanded, the reception of multi-constellation satellites and low-elevation satellites of the antenna is realized, and the requirement of a high-precision positioning module on the antenna is met.

Description

Technical Field

[0001] The utility model relates to the technical field of positioning antennas, in particular to a cavity-type high-precision GNSS antenna device. Background Art

[0002] With the development of GNSS satellite navigation systems, more new demands have been put forward for the navigation, positioning and measurement capabilities of multiple systems;

[0003] Traditional GNSS antennas typically use a stacked microstrip antenna structure, achieving full-band coverage by stacking two independent antenna elements, one operating at high and one at low frequencies. Each antenna element is independently fed by four metal feed posts, resulting in high cost and weight, making it inadequate for high-precision positioning modules. Therefore, we propose a cavity-type high-precision GNSS antenna device to address these technical challenges. Utility Model Content

[0004] In view of this, the present invention lacks a needle, and its main purpose is to provide a cavity-type high-precision GNSS antenna device, which is used to solve the above problems.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions:

[0006] An antenna unit, comprising a PPO board, a first square microstrip patch contrasting therewith, a plurality of rectangular tuning teeth provided on the first square microstrip patch, a first feed point and a second feed point symmetrically provided on the inner side of the PPO board, a second square microstrip patch provided on the PPO board, a cut corner corresponding to the PPO board provided on the second square microstrip patch, a metallized via extending through the first square microstrip patch, and the metallized via extending through the second square microstrip patch, a plurality of radiating arms evenly provided on the second square microstrip patch, a plurality of folded metal serrations provided on the edges of the four outer walls of the PPO board, and a copper cladding provided on the surface of the bottom of the PPO board;

[0007] A communication unit, comprising a phase-shifting network, a pre-amplifier, a filter splitter, a final amplifier, a gain equalizing network, a π-type matching network, and a radio frequency connector, wherein the phase-shifting network is connected to the output ends of the first feed point and the second feed point, the pre-amplifier is connected to the output end of the phase-shifting network, the filter splitter is connected to the output end of the pre-amplifier, the final amplifier is connected to the output end of the filter splitter, the gain equalizing network is connected to the output end of the final amplifier, the π-type matching network is connected to the output end of the gain equalizing network, and the radio frequency connector is connected to the output end of the π-type matching network.

[0008] As a preferred solution, the phase difference between the first feeding point and the second feeding point is 90 degrees.

[0009] As a preferred solution, the second square microstrip patch is located below the first square microstrip patch.

[0010] As a preferred solution, the folded metal serrations are in an inverted 7 shape.

[0011] As a preferred solution, the filter splitter is composed of a one-to-two low insertion loss and wide bandwidth filter and a power splitting and combining circuit.

[0012] As a preferred solution, the final amplifier is composed of a low-power and high-gain amplifier.

[0013] As a preferred solution, the Π-type matching network is a circuit composed of three resistors in a Π-type structure.

[0014] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical solution that:

[0015] This device adopts a single-layer multi-feed design for the antenna radiator, which makes the antenna miniaturized and lightweight, expands the antenna's impedance bandwidth, and enables the antenna to receive multi-constellation satellites and low-elevation-angle satellites, meeting the antenna requirements of high-precision positioning modules.

[0016] By optimizing the active circuit of the device, the number of components in the antenna's amplification and filtering circuits is minimized, meeting functional performance while minimizing costs.

[0017] Through the gain equalization network of this device, the difference between the gains of L1, L2 and L5 is made small, meeting the needs of the positioning terminal.

[0018] In order to more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the top structure of an embodiment of the present utility model;

[0020] Figure 2 This is a schematic diagram of the bottom structure of an embodiment of the present utility model;

[0021] Figure 3 It is a schematic diagram of the network connection of the communication unit of an embodiment of the present utility model.

[0022] Explanation of the accompanying symbols: 1. Radiating arm; 2. First square microstrip patch; 3. PPO board; 4. First feeding point; 5. Second feeding point; 6. Rectangular tuning tooth; 7. Second square microstrip patch; 8. Cut corner; 9. Metallized via; 10. Folded metal serration; 11. Copper cladding; 12. Phase shift network; 13. Pre-amplifier; 14. Filter splitter; 15. Final amplifier; 16. Gain equalization network; 17. Π-type matching network; 18. RF connector. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and implementation examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0025] See also Figures 1 to 3 The present invention provides a cavity-type high-precision GNSS antenna device, comprising:

[0026] The antenna unit includes a PPO board 3, a first square microstrip patch 2 is provided on the PPO board 3, a plurality of rectangular tuning teeth 6 are provided on the first square microstrip patch 2, a first feed point 4 and a second feed point 5 are symmetrically provided on the inner side of the PPO board 3, a second square microstrip patch 7 is provided on the PPO board 3, a cut corner 8 corresponding to the PPO board 3 is provided on the second square microstrip patch 7, a metallized via 9 is provided through the first square microstrip patch 2, and the metallized via 9 passes through the second square microstrip patch 7, a plurality of radiation arms 1 are evenly provided on the second square microstrip patch 7, a plurality of folded metal serrations 10 are provided on the four outer wall edges of the PPO board 3, and a copper clad 11 is provided on the bottom surface of the PPO board 3;

[0027] The communication unit includes a phase-shifting network 12, a pre-amplifier 13, a filter splitter 14, a final amplifier 15, a gain equalizing network 16, a π-type matching network 17 and a radio frequency connector 18. The phase-shifting network 12 is connected to the output ends of the first feed point 4 and the second feed point 5, the pre-amplifier 13 is connected to the output end of the phase-shifting network 12, the filter splitter 14 is connected to the output end of the pre-amplifier 13, the final amplifier 15 is connected to the output end of the filter splitter 14, the gain equalizing network 16 is connected to the output end of the final amplifier 15, the π-type matching network 17 is connected to the output end of the gain equalizing network 16, and the radio frequency connector 18 is connected to the output end of the π-type matching network 17.

[0028] During the use of this device, the device has the characteristics of miniaturization, high gain, wide axial ratio bandwidth, strong multipath suppression capability, and wide frequency bandwidth. It can receive multi-constellation full-band L1, L2 and L5 signals. The first square microstrip patch 2 realizes the reception of L1 satellite, and the second square microstrip patch 7 realizes the reception of L2 and L5 satellites. The PPO board 3 is a PPO material with a dielectric constant of 4.4. The first square microstrip patch 2 also includes a coaxial probe, which is connected to the first feeding point 4 and the second feeding point 5 respectively. This device generates resonance at the positions of the first feeding point 4 and the second feeding point 5 through the action between the radiator and the bottom ground, thereby realizing L1, L2, and L5 signal reception. The coaxial probe introduces the signal into the phase shift network 12 for processing;

[0029] The first square microstrip patch 2 has good symmetry, making it easier to achieve circular polarization. The first feed point 4 and the second feed point 5 are symmetrically and evenly distributed on the first square microstrip patch 2. The first feed point 4 and the second feed point 5 are fed by a coaxial probe to introduce the received signal into the copper clad 11. Adding five rectangular tuning teeth 6 to the first square microstrip patch 2 helps to adjust the resonant frequency so that the antenna gain reaches the maximum within the L1 frequency band.

[0030] The second square microstrip patch 7 receives satellite L2 and L5 signals. The four legs of the second square microstrip patch 7 are cut off at 8 to facilitate circular polarization. The first square microstrip patch 2 and the second square microstrip patch 7 are connected by a central metallized via 9, so that the first feed point 4 and the second feed point 5 can simultaneously receive L1, L2, and L5 frequency band signals.

[0031] Two radiating arms 1 are loaded on each side of the second square microstrip patch 7. The radiating arms 1 are connected to the radiating surface of the second square microstrip patch 7, which is equivalent to loading a capacitor to compensate for the impedance, thereby changing the current path of the radiating surface and expanding the impedance bandwidth of the device, so that the antenna can receive L2 and L5 satellite signals.

[0032] The four edges of the PPO board 3 are respectively loaded with three inverted "7" folded metal serrations 10, which load the radiating arm 1 coupling parasitic unit, thereby improving the damaged current path and suppressing the multiple resonance modes. At the same time, the impedance of L2 and L5 are matched, and their impedance bandwidth is expanded, and the frequency bandwidth of L2 and L5 is increased. At the same time, the antenna gain bandwidth is widened and the low elevation angle gain is increased, which can better receive low elevation angle satellites;

[0033] By covering the entire bottom surface of the PPO board 3 with copper cladding 11, the ground of the device can be better contacted with the ground of the RF front-end PCB, thereby increasing the ground area, which can effectively improve the effective gain of the device and suppress multipath signals, thereby improving the ability of the device to suppress multipath signals. The RF front-end PCB is an existing mature technology and will not be described in detail in this article.

[0034] The phase shift network 12 is composed of a low insertion loss 3dB bridge, which synthesizes signals of different phases into a signal of the same phase. The signal from the phase shift network 12 is amplified by a low-noise and low-power preamplifier 13, and then filtered, split, and combined by a filter splitter 14.

[0035] The filter splitter 14 is composed of a two-way low insertion loss wide bandwidth filter and a power splitter / combiner circuit. The filter splitter 14 can perform bandpass filtering on the amplified signal, allowing only L1, L2, and L5 frequency band signals to pass through and suppressing signals in other frequency bands.

[0036] After the signal comes out of the filter splitter 14, it is amplified by the final amplifier 15. The final amplifier 15 is composed of a low-power and high-gain amplifier to amplify the signal to the gain required by the device;

[0037] The signal then passes through the gain equalization network 16 to adjust the flatness. Because the amplification of the pre-amplifier 13 and the final amplifier 15 is nonlinear, the gains of L1, L2, and L5 after the signal exits the final amplifier 15 have different gain values. The gain equalization network 16 is composed of resistors, capacitors, and inductors, which can adjust the gains of L1, L2, and L5 to keep the gain difference within 1dB.

[0038] After the signal comes out of the gain equalization network 16, it passes through the π-type matching network 17. The π-type matching network 17 is a circuit composed of three resistors in a π-shaped structure. Its function is to first make the signal gain meet the requirements of the output end, and secondly to adjust the output impedance matching and optimize the output standing wave ratio.

[0039] Finally, the signal enters the receiver through the RF connector 18 for processing. The receiver is a mature existing technology and will not be described in detail in this article.

[0040] See also Figures 1 to 3 The phase difference between the first feed point 4 and the second feed point 5 is 90 degrees. During the use of the device, by setting the phase difference between the first feed point 4 and the second feed point 5 to 90 degrees, it can have good symmetry and more easily achieve circular polarization.

[0041] See also Figures 1 to 3 The second square microstrip patch 7 is located below the first square microstrip patch 2. During use of the device, the first square microstrip patch 2 is used to receive satellite L1 signals, and the second square microstrip patch 7 is used to receive satellite L2 and L5 signals.

[0042] See also Figures 1 to 3 The folded metal saw teeth 10 are in an inverted 7 shape. During the use of the device, the folded metal saw teeth 10 are in an inverted 7 shape, which can improve the damaged current path and suppress the generated multiple resonance modes.

[0043] See also Figures 1 to 3 The filter splitter 14 is composed of a low insertion loss, wide bandwidth filter and a power splitter / combiner circuit. During use of the device, the filter splitter 14 can perform bandpass filtering on the amplified signal, allowing only L1, L2, and L5 frequency band signals to pass through and suppressing signals in other frequency bands.

[0044] See also Figures 1 to 3 The final amplifier 15 is composed of a low-power high-gain amplifier. During the use of this device, the final amplifier 15 amplifies the signal to the gain required by the antenna.

[0045] See also Figures 1 to 3 The π-type matching network 17 is a circuit composed of three resistors in a π-type structure. During the use of this device, the π-type matching network 17 firstly makes the signal gain meet the requirements of the output end, and secondly adjusts the output impedance matching to optimize the output standing wave ratio.

[0046] In summary, this device adopts a single-layer multi-feed design for the antenna radiator, which makes the antenna miniaturized, expands the impedance bandwidth of the antenna, and enables the antenna to receive multi-constellation satellites and low-elevation-angle satellites, meeting the antenna requirements of the high-precision positioning module.

[0047] By optimizing the active circuit of the device, the number of components in the antenna's amplification and filtering circuits is minimized, meeting functional performance while minimizing costs.

[0048] Through the gain equalization network 16 of the device, the difference between the gains of L1, L2 and L5 is reduced to meet the needs of the positioning terminal.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A cavity-type high-precision GNSS antenna device, characterized in that: include: An antenna unit, comprising a PPO board (3), a first square microstrip patch (2) arranged on the PPO board (3), a plurality of rectangular tuning teeth (6) arranged on the first square microstrip patch (2), a first feed point (4) and a second feed point (5) symmetrically arranged on the inner side of the PPO board (3), a second square microstrip patch (7) arranged on the PPO board (3), a cut corner (8) corresponding to the PPO board (3) opened on the second square microstrip patch (7), a metallized via (9) extending through the first square microstrip patch (2), and the metallized via (9) extending through the second square microstrip patch (7), a plurality of radiation arms (1) uniformly arranged on the second square microstrip patch (7), a plurality of folded metal serrations (10) arranged on the edges of the four outer walls of the PPO board (3), and a copper coating (11) provided on the bottom surface of the PPO board (3); A communication unit, comprising a phase shift network (12), a pre-amplifier (13), a filter splitter (14), a final amplifier (15), a gain equalization network (16), a Π-type matching network (17) and a radio frequency connector (18), wherein the phase shift network (12) is connected to the output ends of the first feed point (4) and the second feed point (5), the pre-amplifier (13) is connected to the output end of the phase shift network (12), the filter splitter (14) is connected to the output end of the pre-amplifier (13), the final amplifier (15) is connected to the output end of the filter splitter (14), the gain equalization network (16) is connected to the output end of the final amplifier (15), the Π-type matching network (17) is connected to the output end of the gain equalization network (16), and the radio frequency connector (18) is connected to the output end of the Π-type matching network (17).

2. The cavity-type high-precision GNSS antenna device according to claim 1, characterized in that: The phase difference between the first feeding point (4) and the second feeding point (5) is 90 degrees.

3. The cavity-type high-precision GNSS antenna device according to claim 1, characterized in that: The second square microstrip patch (7) is located below the first square microstrip patch (2).

4. The cavity-type high-precision GNSS antenna device according to claim 1, characterized in that: The folded metal saw teeth (10) are in an inverted 7 shape.

5. The cavity-type high-precision GNSS antenna device according to claim 4, characterized in that: The filter splitter (14) is composed of a one-to-two low insertion loss wide bandwidth filter and a power splitting and combining circuit.

6. The cavity-type high-precision GNSS antenna device according to claim 1, characterized in that: The final amplifier (15) is composed of a low-power-consumption and high-gain amplifier.

7. The cavity-type high-precision GNSS antenna device according to claim 1, characterized in that: The Π-type matching network (17) is a circuit composed of three resistors in a Π-type structure.

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