Antenna based on coplanar waveguide feeder
By adopting a coplanar waveguide feeder structure in microstrip antennas, the problems of insufficient dual-polar feeding complexity and isolation are solved, and the dual-polarization and impedance matching are supported on a single antenna, which improves the compactness of the antenna and Isolation degree.
Patent Information
- Application Number
- CN202420767302.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-12
- Publication Date
- 2025-01-17
- Estimated Expiration
- 2034-04-12
AI Technical Summary
When existing microstrip antennas achieve dual polarization, the feed network structure is complex, resulting in insufficient isolation and waste of space, difficulty in matching impedance, affecting the compactness and integration of the antenna.
Using a coplanar waveguide feeder structure, the receiving and transmitting coplanar waveguide feeder is set on the PCB board to achieve a characteristic impedance of 50Ω and support horizontal and vertical polarization on a single-antenna line, simplifying the feeding network, reducing coupling, and improving isolation .
It realizes the support of dual polarization on a single antenna at the same time, simplifies the feeding structure, improves isolation and compactness, flexibly performs impedance matching, and reduces space waste.
Smart Images
Figure CN222365722U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of antenna technology, and in particular to an antenna based on a coplanar waveguide feeder. Background Art
[0002] With the rapid development of modern communication systems, microstrip antennas are increasingly used in mobile satellite communication systems, radar tracking, RFID, WLAN, etc. As the requirements for antennas become higher and higher, they must not only meet performance requirements, but also have more requirements for appearance and system integration, especially the research on miniaturization, which is becoming more and more important. Existing microstrip antennas are usually divided into single-polarization antennas and dual-polarization antennas. Single-polarization antennas usually need to be used with a bridge, which requires a certain increase in PCB area; conventional dual-polarization antennas have relatively strict requirements on isolation, and the impedance of the RF IC transmitting and receiving ports is usually 50Ω, but the edge impedance of conventional 5.8GHz antennas is between 100 and 200Ω. In order to match the impedance of the transmitting and receiving feeder, the width of the feeder is relatively large, which is not convenient for PCB layout. Therefore, how to improve the isolation between the two polarization feeding ports is a difficult problem of dual-polarization antennas. Currently, effective technologies include: (1) using differential feeding to make the zero points of the two polarizations coincide and avoid coupling; (2) using air bridge technology between the two polarization feed lines, that is, reducing the line width at the cross section of the feed lines to reduce coupling, and matching the feeding circuit at the same time; (3) using multi-path balancing technology, that is, there are multiple coupling paths between ports 1 and 2, and the multi-path coupling signals are superimposed to 0 to achieve high isolation; (4) using different physical structures for feeding, such as using probes and coupling methods to excite the two polarizations respectively. The above methods can achieve an isolation of -25dB to -30dB, but the common characteristics are that the feeding network structure is very complex, the introduction of air bridges, power dividers, etc. brings losses, and the antenna unit is not compact enough, resulting in a waste of space. Utility Model Content
[0003] The utility model aims to solve the technical problems existing in the background technology and proposes an antenna based on a coplanar waveguide feeder, comprising a PCB board, the PCB board comprising a dielectric substrate, the dielectric substrate being provided with a top surface device layer and a bottom surface grounding metal layer at the top end surface and the bottom end surface respectively, the top surface device layer comprising a millimeter wave radar chip, a receiving coplanar waveguide feeder and a transmitting coplanar waveguide feeder, the dielectric substrate being further provided with an antenna at the top end surface, one end of the receiving coplanar waveguide feeder and the transmitting coplanar waveguide feeder being respectively connected to a receiving pin and a transmitting pin of the millimeter wave radar chip, and the other ends of the receiving coplanar waveguide feeder and the transmitting coplanar waveguide feeder being respectively connected to the antenna.
[0004] Furthermore, the characteristic impedance of the receiving coplanar waveguide feeder and the transmitting coplanar waveguide feeder is 50Ω, and the operating frequency is 5.8GHz±75MHz.
[0005] Furthermore, the thickness of the top device layer and the bottom grounding metal layer is 17-35 um, the thickness of the dielectric substrate is 1.0-1.6 mm, and the dielectric constant is 4-5.
[0006] Furthermore, metallized grounding vias are provided on both sides of the receiving coplanar wave feeder and the transmitting coplanar waveguide feeder, and the diameter of the metallized grounding vias is 0.2-0.3 mm.
[0007] Furthermore, the operating center frequency of the antenna is 5.8 GHz.
[0008] Furthermore, the shape of the antenna is rectangular, circular, octagonal or other symmetrical images.
[0009] Furthermore, the inner conductor width and the gap width of the coplanar waveguide on the PCB board are impedance matched with the chip pin width of the radio frequency IC on the PCB board.
[0010] Furthermore, the inner conductor width and the gap width of the coplanar waveguide on the PCB board are 0.2-0.5 mm.
[0011] Compared with the prior art, the utility model has the following beneficial technical effects: the utility model can realize dual polarization on a single antenna, requiring the antenna unit to simultaneously support two high-isolation polarization modes. In order to overcome the complexity of dual polarization feeding, a coplanar waveguide feeding structure is adopted. Since the coplanar waveguide can simultaneously support odd mode and even mode, the horizontal and vertical polarization of the slot antenna can be simultaneously excited. In this way, two polarization modes and two feeding modes can be respectively realized on a single slot antenna and a coplanar waveguide, reflecting the compactness of the antenna structure. At the same time, the inner conductor width and the slot width of the coplanar waveguide can be flexibly designed for impedance matching according to the chip pin width of the RF IC. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 This is a top view of the utility model;
[0013] Figure 2 This is a cross-sectional view of the utility model. DETAILED DESCRIPTION
[0014] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.
[0015] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.
[0016] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or a specific connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.
[0017] The specific embodiments of the present utility model are described in detail below with reference to the accompanying drawings.
[0018] like Figure 1-Figure 2 As shown, the utility model proposes an antenna based on a coplanar waveguide feeder, including a PCB board 10, the PCB board 10 includes a dielectric substrate 7, the dielectric substrate 7 is respectively provided with a top surface device layer 3 and a bottom surface grounding metal layer 5 on the top end surface and the bottom end surface, the top surface device layer 3 includes a millimeter wave radar chip 6, a receiving coplanar waveguide feeder 1 and a transmitting coplanar waveguide feeder 2, the dielectric substrate 7 is also provided with an antenna 4 on the top end surface, one end of the receiving coplanar waveguide feeder 1 and the transmitting coplanar waveguide feeder 2 are respectively connected to the receiving pin and the transmitting pin of the millimeter wave radar chip 6, and the other ends of the receiving coplanar waveguide feeder 1 and the transmitting coplanar waveguide feeder 2 are respectively connected to the antenna 4.
[0019] Furthermore, in this embodiment, the characteristic impedance of the receiving coplanar waveguide feeder line 1 and the transmitting coplanar waveguide feeder line 2 is 50Ω, and the operating frequency is 5.8 GHz±75 MHz.
[0020] Furthermore, in this embodiment, the thickness of the top device layer 3 and the bottom grounding metal layer 5 is 17-35 um, the thickness of the dielectric substrate 7 is 1.0-1.6 mm, and the dielectric constant is 4-5.
[0021] Furthermore, in the present embodiment, both sides of the receiving coplanar wave feeder line 1 and the transmitting coplanar waveguide feeder line 2 are provided with metallized ground vias, and the diameter of the metallized ground vias is 0.2-0.3 mm.
[0022] Furthermore, in this embodiment, the operating center frequency of the antenna is 5.8 GHz ± 75 MHz.
[0023] Further, in this embodiment, the shape of the antenna is rectangular, circular, octagonal or other symmetrical images.
[0024] Furthermore, in this embodiment, the inner conductor width and the gap width of the coplanar waveguide on the PCB board 10 are impedance matched with the chip pin width of the RF IC on the PCB board 10 .
[0025] Furthermore, in this embodiment, the inner conductor width and the gap width of the coplanar waveguide on the PCB board 10 are 0.2-0.5 mm.
[0026] In summary, the utility model has the following beneficial effects: the utility model can realize dual polarization on a single antenna, requiring the antenna unit to simultaneously support two high-isolation polarization modes. In order to overcome the complexity of dual-polarization feeding, a coplanar waveguide feeding structure is adopted. Since the coplanar waveguide can simultaneously support odd mode and even mode, the horizontal and vertical polarization of the slot antenna can be simultaneously excited. In this way, two polarization modes and two feeding modes can be realized on a single slot antenna and a coplanar waveguide, respectively, reflecting the compactness of the antenna structure. At the same time, the inner conductor width and the gap width of the coplanar waveguide can be flexibly designed for impedance matching according to the chip pin width of the RF IC.
[0027] The above are one or more implementation methods provided in combination with specific content, and it is not intended that the specific implementation of the utility model is limited to these descriptions. Any method, structure, etc. similar to or identical to the method, structure, etc. of the utility model, or any technical deduction or replacement based on the concept of the utility model, shall be deemed to be within the protection scope of the utility model.
Claims
1. An antenna based on a coplanar waveguide feeder, characterized in that: The invention comprises a PCB board (10), wherein the PCB board (10) comprises a dielectric substrate (7), wherein a top surface device layer (3) and a bottom surface grounding metal layer (5) are respectively arranged on the top end surface and the bottom end surface of the dielectric substrate (7), wherein the top surface device layer (3) comprises a millimeter wave radar chip (6), a receiving coplanar waveguide feeder (1) and a transmitting coplanar waveguide feeder (2), and wherein an antenna (4) is also arranged on the top end surface of the dielectric substrate (7), wherein one end of the receiving coplanar waveguide feeder (1) and the transmitting coplanar waveguide feeder (2) are respectively connected to the receiving pin and the transmitting pin of the millimeter wave radar chip (6), and the other end of the receiving coplanar waveguide feeder (1) and the transmitting coplanar waveguide feeder (2) are respectively connected to the antenna (4).
2. The antenna based on a coplanar waveguide feeder according to claim 1, characterized in that: The characteristic impedance of the receiving coplanar waveguide feeder (1) and the transmitting coplanar waveguide feeder (2) is 50Ω, and the operating center frequency is 5.8 GHz.
3. The antenna based on a coplanar waveguide feeder according to claim 1, characterized in that: The thickness of the top device layer (3) and the bottom grounding metal layer (5) is 17-35 um, the thickness of the dielectric substrate (7) is 1.0-1.6 mm, and the dielectric constant is 4-5.
4. The antenna based on a coplanar waveguide feeder according to claim 1, characterized in that: The receiving coplanar waveguide feeder (1) and the transmitting coplanar waveguide feeder (2) are both provided with metallized grounding vias on both sides, and the diameter of the metallized grounding vias is 0.2-0.3 mm.
5. The antenna based on a coplanar waveguide feeder according to claim 1, characterized in that: The operating frequency of the antenna (4) is 5.8 GHz ± 75 MHz.
6. The antenna based on a coplanar waveguide feeder according to claim 1, characterized in that: The antenna (4) is arranged in a symmetrical shape.
7. The antenna based on a coplanar waveguide feeder according to claim 1, characterized in that: The inner conductor width and the gap width of the coplanar waveguide on the PCB board (10) are impedance matched with the chip pin width of the radio frequency IC on the PCB board (10).
8. The antenna based on a coplanar waveguide feeder according to claim 7, characterized in that: The inner conductor width and the gap width of the coplanar waveguide on the PCB board (10) are 0.2-0.5 mm.