A high-isolation primary lens antenna system and millimeter wave radar sensor

Abstract

The application relates to the technical field of millimeter wave antenna, in particular to a high-isolation primary lens antenna system and a millimeter wave radar sensor, which comprises a high-frequency circuit board, one side of the high-frequency circuit board is provided with a microstrip antenna, the microstrip antenna is composed of two parallel independent antenna surfaces and matching transmission lines, the left antenna surface is a receiving antenna, and the right antenna surface is a transmitting antenna; the high-frequency circuit board is provided with a cover plate, the cover plate is located above the microstrip antenna, and a primary lens antenna is arranged on the cover plate; the microstrip antenna is designed to be independent and parallel, the radar radio frequency circuit is simplified, high isolation of the radar receiving and transmitting channels is realized, and the overall performance of the radar is improved; the product module is miniaturized and the flexibility of overall application is realized through the shared multi-stage lens antenna system, and the production and debugging cost of the product is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of millimeter wave antenna, in particular to a high-isolation primary lens antenna system and a millimeter wave radar sensor. BACKGROUND

[0002] With the development of industrial intelligent manufacturing and industrial internet of things, higher requirements are put forward for the performance of the level radar sensor. The traditional 24GHz-26GHz level radar sensor has a large volume, and the test precision is limited by the physical characteristics of electromagnetic waves. For application occasions with high test precision and complex test environment, the use demand cannot be met. Higher test precision and adaptability to complex working conditions promote the continuous development of the industry. The level radar sensor using 76GHz-81GHz (hereinafter referred to as 80GHz) frequency band will become the mainstream of the new generation of products. The corresponding frequency transmitting and receiving antenna system of the product has a key influence on the overall performance.

[0003] The 80GHz frequency band radar level meter product in the current market develops rapidly, but there are few models in practical use at present. The products of foreign well-known brands are relatively mature, and most of them use discrete chip to build a radar system, which is complex in design and high in cost. At the same time, a single antenna shared by transmitting and receiving is used as an electromagnetic wave transmitting and receiving channel in the design of the antenna system, and the isolation of the transmitting and receiving channels needs to be ensured by an additional radio frequency chip circuit.

[0004] In order to simplify the system, the domestic products mainly use the radio frequency circuit designed on the high-frequency circuit board to realize the single antenna shared by transmitting and receiving. It is difficult to realize high isolation between the transmitting and receiving channels, which will affect the performance of the final radar sensor product. Based on this, the present application designs a high-isolation primary lens antenna system and a millimeter wave radar sensor to solve the above problems. SUMMARY

[0005] The present application aims to provide a high-isolation primary lens antenna system and a millimeter wave radar sensor to solve the above technical problems.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a high-isolation millimeter wave sensor antenna system, comprising a high-frequency circuit board, a microstrip antenna is arranged on one side of the high-frequency circuit board, the microstrip antenna is composed of two parallel arranged independent antenna surfaces and their matching transmission lines, and the left antenna surface is a receiving antenna and the right antenna surface is a transmitting antenna, the high-frequency circuit board is provided with a cover plate, and the cover plate is located above the microstrip antenna, and a primary lens antenna is arranged on the cover plate.

[0007] Preferably, a lens clasp is arranged on the cover plate, and the primary lens antenna is tightly installed on the cover plate through the lens clasp.

[0008] Preferably, the cover plate is fixed to the high-frequency circuit board by screws.

[0009] Preferably, the cover plate inner cavity constitutes a cylindrical trapezoidal cavity from the microstrip antenna plane to the primary lens antenna plane.

[0010] A millimeter wave radar sensor, comprising a radar sensor head, a secondary lens antenna, a connecting piece and a connecting flange, the radar sensor head is provided with the high-isolation primary lens antenna system according to any one of claims 1-4, the radar sensor head is connected with the connecting piece at one end, the connecting piece is detachably provided with the secondary lens antenna at the end away from the radar sensor head, and the high-isolation primary lens antenna system is aligned with the center line of the secondary lens antenna, and the secondary lens antenna is detachably provided with the connecting flange away from the connecting piece.

[0011] Preferably, the radar sensor head comprises a module shell and a module upper cover matched with the module shell, the module upper cover is provided with a module circuit board support on the side close to the module shell, the high-isolation primary lens antenna system is installed at the top of the inner cavity of the module shell, and the high-isolation primary lens antenna system is centrally and symmetrically arranged with the cylindrical opening of the module shell.

[0012] Preferably, the connecting piece and the radar sensor head are detachably connected through fine threads.

[0013] Preferably, rubber rings are arranged between the radar sensor head, the secondary lens antenna, the connecting piece and the connecting flange as sealing materials.

[0014] Compared with the prior art, the present application has the following beneficial effects:

[0015] The present application simplifies the radar radio frequency circuit by designing the transceiving independent and parallel distributed microstrip antenna, realizes high isolation of the radar transceiving channel, and improves the overall performance of the radar; the product module is miniaturized and the overall application flexibility is realized through the shared multi-stage lens antenna system, and the production and debugging costs of the product are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1 It is a structural schematic diagram of the high-isolation millimeter wave sensor antenna system in the present application.

[0018] Figure 2This is a schematic diagram of the structure between the high-frequency circuit board and the microstrip circuit in this invention;

[0019] Figure 3 This is a top view of the high isolation millimeter-wave sensor antenna system of the present invention;

[0020] Figure 4 This is an exploded view of the high isolation millimeter-wave sensor antenna system of the present invention;

[0021] Figure 5 This is an exploded view of the structure of the millimeter-wave radar sensor in this invention;

[0022] Figure 6 This is an exploded view of the radar sensor head structure in this invention.

[0023] The attached diagram lists the components represented by each number as follows:

[0024] 1. High-frequency circuit board; 2. Microstrip antenna; 3. Cover plate; 4. Primary lens antenna; 5. Lens retainer; 6. Radar sensor head; 61. Module housing; 62. Module top cover; 63. Module circuit board bracket; 7. Secondary lens antenna; 8. Connector; 9. Connecting flange. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0026] Please see Figures 1-6 This invention provides a technical solution: a high-isolation millimeter-wave sensor antenna system, including a high-frequency circuit board 1. A microstrip antenna 2 is disposed on one side of the high-frequency circuit board 1. The microstrip antenna 2 is composed of two independent antenna surfaces arranged in parallel and their matching transmission lines. The left antenna surface is the receiving antenna, and the right antenna surface is the transmitting antenna. A cover plate 3 is disposed on the high-frequency circuit board 1, and the cover plate 3 is located above the microstrip antenna 2. A primary lens antenna 4 is disposed on the cover plate 3. The independent antenna group for transmitting and receiving can simplify the radio frequency circuit and provide higher isolation of the transceiver system for the radar sensor, so as to achieve better test accuracy.

[0027] Specifically, a lens retaining ring 5 is provided on the cover plate 3, and the primary lens antenna 4 is securely mounted on the cover plate 3 by means of the lens retaining ring 5.

[0028] Specifically, the cover plate 3 is fixed to the high-frequency circuit board 1 by screws.

[0029] Specifically, the inner cavity of the cover plate 3 forms a cylindrical trapezoidal cavity from the plane of the microstrip antenna 2 to the plane of the primary lens antenna 4.

[0030] A millimeter-wave radar sensor includes a radar sensor head 6, a secondary lens antenna 7, a connector 8, and a connecting flange 9. The radar sensor head 6 houses a high-isolation primary lens antenna system as claimed in any one of claims 1-4. One end of the radar sensor head 6 is connected to the connector 8. The secondary lens antenna 7 is detachably mounted on the end of the connector 8 furthest from the radar sensor head 6, and the high-isolation primary lens antenna system is aligned with the centerline of the secondary lens antenna 7. The secondary lens antenna 7 is detachably mounted on the connecting flange 9 furthest from the connector 8. The secondary lens antenna 7 is detachably connected to both the connector 8 and the connecting flange 9, allowing for different usage environments and equipment installation requirements to be met by changing the size and materials of the secondary lens antenna 7. Furthermore, changing the connector 8 allows for the matching and installation of secondary lens antennas of different sizes or the design requirements of multi-stage lens antenna groups.

[0031] Specifically, the radar sensor head 6 includes a module housing 61 and a module cover 62 that cooperates with the module housing 61. A module circuit board bracket 63 is provided on one side of the module cover 62 near the module housing 61. A high isolation primary lens antenna system is installed on the top of the inner cavity of the module housing 61. The high isolation primary lens antenna system is symmetrically arranged with the cylindrical opening of the module housing 61.

[0032] Specifically, the connector 8 is detachably connected to the radar sensor head 6 via fine threads, allowing for installation and disassembly.

[0033] Specifically, rubber rings are installed between the radar sensor head 6, secondary lens antenna 7, connector 8, and connecting flange 9 as sealing materials to improve the sealing performance of the components during installation.

[0034] A specific application example of this embodiment is as follows:

[0035] like Figure 2 As shown, the microstrip antenna 2 consists of two independent antenna surfaces arranged in parallel on the same high-frequency circuit board 1 and their matching transmission lines. The left antenna surface is the receiving antenna of the radar sensor, and the right antenna surface is the transmitting antenna of the radar sensor. This independent transmitting and receiving antenna group simplifies the RF circuitry while providing higher isolation between the transmitting and receiving systems for the radar sensor, thus achieving better testing accuracy.

[0036] like Figure 1 , Figure 3 and Figure 4As shown, the primary lens antenna system consists of a high-frequency circuit board 1, a cover plate 3, a primary lens antenna 4, and a lens retaining ring 5. The cover plate 3 is mounted on the high-frequency circuit board 1 with screws, and has a cylindrical opening cut out above the microstrip antenna 2. The primary lens antenna 4 is securely mounted on the cover plate 3 using the lens retaining ring 5. The primary lens antenna system assembly is assembled inside the radar sensor housing as part of the radar sensor head module, with the primary lens antenna 4 aligned with the centerline of the subsequent multi-stage lens antennas.

[0037] like Figure 5 and Figure 6 As shown, the radar sensor head 6 houses a radar head module (including a primary lens antenna system assembly). The secondary lens antenna 7 is sealed between the connector 8 and the connecting flange 9, forming an external secondary lens antenna system assembly. A purge structure can be designed inside the connector 8, allowing for the cleaning of deposits on the lens surface via air blowing. The connector 8 is connected to the head 6 via fine threads. Rubber rings are used as sealing materials between the radar sensor head 6, connector 8, secondary lens 7, and connecting flange 9.

[0038] By changing the size and materials of the secondary lens antenna 7, different usage environments and equipment installation requirements can be met. By changing the connector 8, the matching and installation of secondary lens antennas 8 of different sizes or the design requirements of multi-stage lens antenna groups can be met.

[0039] This patent designs a microstrip antenna with independent transmit and receive channels, arranged in parallel to achieve high isolation between the transmit and receive channels through spatial separation. Furthermore, since the transmit and receive antennas are separated, they can be independently connected to the electromagnetic wave transmit (Tx) and electromagnetic wave receive (Rx) pins of the integrated chip, simplifying the design by eliminating the need for a combined RF circuit chip or board-level circuit for the transmit and receive channels, thus reducing the complexity of the radar system. High isolation between the transmit and receive antennas has a decisive impact on the isolation between the transmit and receive channels of the entire radar sensor system. High isolation between the transmit and receive channels of the radar system can significantly reduce the impact of electromagnetic wave energy emitted from the transmit channel on the floor noise of the receive channel, thereby improving the signal-to-noise ratio of the radar system and ultimately enhancing the testing accuracy and range of the radar sensor.

[0040] The combination of microstrip antennas and lens antennas enables the miniaturization and modularization of primary antenna systems. The combination itself forms a small antenna system, transmitting electromagnetic signals from a chip on a circuit board into space. Simultaneously, the lens antenna can also serve as a package cover, forming a closed structure together with the radar module housing, achieving product modularity. Modular radar modules reduce the difficulty of overall assembly and improve production efficiency.

[0041] The shared multi-stage lens antenna system reduces the product size and is compatible with the common traditional shape of industrial radar sensor products. At the same time, while keeping the primary lens module unchanged, it can flexibly change the antenna aperture by expanding the secondary lens antenna, or use a multi-stage lens group antenna system to optimize certain specific performance.

[0042] Furthermore, this design method can be extended to use in lens antenna systems with two or more lenses.

[0043] In the description of this invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "other end," "upper," "side," "top," "inner," "front," "center," "both ends," etc., indicate the orientation or positional relationship based on the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that variations may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A millimeter-wave radar sensor, characterized in that: The device includes a radar sensor head (6), a secondary lens antenna (7), a connector (8), and a connecting flange (9). The radar sensor head (6) is equipped with a high-isolation primary lens antenna system. One end of the radar sensor head (6) is connected to the connector (8). The secondary lens antenna (7) is detachably provided at the end of the connector (8) away from the radar sensor head (6). The high-isolation primary lens antenna system is aligned with the centerline of the secondary lens antenna (7). The secondary lens antenna (7) is detachably provided with a connecting flange (9) away from the connector (8). The high isolation primary lens antenna system includes a high frequency circuit board (1), on one side of which a microstrip antenna (2) is provided. The microstrip antenna (2) is composed of two independent antenna surfaces arranged in parallel and their matching transmission lines. The left antenna surface is the receiving antenna and the right antenna surface is the transmitting antenna. The high frequency circuit board (1) is provided with a cover plate (3), which is located above the microstrip antenna (2). A primary lens antenna (4) is provided on the cover plate (3).

2. The millimeter-wave radar sensor according to claim 1, characterized in that: The cover plate (3) is provided with a lens retainer (5), and the primary lens antenna (4) is clamped and installed on the cover plate (3) through the lens retainer (5).

3. A millimeter-wave radar sensor according to claim 1, characterized in that: The cover plate (3) is fixed to the high-frequency circuit board (1) by screws.

4. A millimeter-wave radar sensor according to claim 1, characterized in that: The inner cavity of the cover plate (3) forms a cylindrical trapezoidal cavity from the plane of the microstrip antenna (2) to the plane of the primary lens antenna (4).

5. A millimeter-wave radar sensor according to claim 1, characterized in that: The radar sensor head (6) includes a module housing (61) and a module cover (62) that cooperates with the module housing (61). A module circuit board bracket (63) is provided on one side of the module cover (62) near the module housing (61). A high isolation primary lens antenna system is installed on the top of the inner cavity of the module housing (61). The high isolation primary lens antenna system is symmetrically arranged with the cylindrical opening of the module housing (61).

6. A millimeter-wave radar sensor according to claim 1, characterized in that: The connector (8) is detachably connected to the radar sensor head (6) via a fine thread.

7. A millimeter-wave radar sensor according to claim 1, characterized in that: Rubber rings are provided as sealing material between the radar sensor head (6), secondary lens antenna (7), connector (8) and connecting flange (9).

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