Radar sensor

Abstract

The utility model discloses a radar sensor which comprises a substrate, and a first omnidirectional antenna, a second omnidirectional antenna and a radar module which are arranged on the substrate, and the radar module is connected with the first omnidirectional antenna and the second omnidirectional antenna to control the first omnidirectional antenna and the second omnidirectional antenna. The substrate comprises a first surface and a second surface which are arranged oppositely, the maximum radiation direction of the first omnidirectional antenna faces the outer side of the first surface, and the maximum radiation direction of the second omnidirectional antenna faces the outer side of the second surface. According to the radar sensor, 360-degree omnibearing detection is realized by adopting the first omnibearing antenna and the second omnibearing antenna, and meanwhile, the maximum radiation directions of the first omnibearing antenna and the second omnibearing antenna face two different directions, so that the coupling radiation between the two antennas is reduced, and the isolation between the two antennas is greatly improved.

Description

Technical Field

[0001] This utility model belongs to the field of antenna technology, specifically relating to a radar sensor. Background Technology

[0002] Radar sensors, especially millimeter-wave radar sensors, have been widely used in fields such as autonomous vehicles, drones, and smart homes in recent years. These sensors detect the position, velocity, and other information of target objects by transmitting and receiving millimeter-wave signals, and have advantages such as strong penetration, strong anti-interference ability, and high detection accuracy.

[0003] However, most existing millimeter-wave radar sensors are used in larger devices. These sensors are bulky, complex in design, and optimized for directional detection. For example, automotive radar primarily focuses on the driving environment in front or behind, while drone radar focuses on a specific flight direction. These sensors often employ microstrip antennas, which offer strong directionality and good gain.

[0004] In desktop applications, such as smart lamps, fans, air purifiers, and humidifiers, sensors are needed to monitor the environment in real time and detect the position and movement of people or objects in the vicinity. These applications require sensors with omnidirectional detection capabilities to perceive changes in the surrounding environment from all 360 degrees, but currently, there are few suitable solutions that meet this requirement.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0006] The purpose of this invention is to provide a radar sensor that can achieve omnidirectional azimuth detection while having a high degree of isolation.

[0007] To achieve the above objectives, the technical solution provided by a specific embodiment of this utility model is as follows:

[0008] A radar sensor includes a substrate and a first omnidirectional antenna, a second omnidirectional antenna, and a radar module disposed on the substrate. The radar module is connected to the first omnidirectional antenna and the second omnidirectional antenna to control the first omnidirectional antenna and the second omnidirectional antenna. The substrate includes a first surface and a second surface disposed opposite to each other. The maximum radiation direction of the first omnidirectional antenna is directed towards the outside of the first surface, and the maximum radiation direction of the second omnidirectional antenna is directed towards the outside of the second surface.

[0009] In one or more embodiments of this utility model, the maximum radiation direction of the first omnidirectional antenna is opposite to the maximum radiation direction of the second omnidirectional antenna.

[0010] In one or more embodiments of the present invention, the maximum radiation direction of the first omnidirectional antenna and the maximum radiation direction of the second omnidirectional antenna are perpendicular to the first surface and / or the second surface.

[0011] In one or more embodiments of the present invention, the radiator of the first omnidirectional antenna is disposed on a first surface, and the radiator of the second omnidirectional antenna is disposed on a second surface.

[0012] In one or more embodiments of this utility model, the radiation pattern of the first omnidirectional antenna is opposite to the null point of the radiation pattern of the second omnidirectional antenna.

[0013] In one or more embodiments of this utility model, the first omnidirectional antenna and the second omnidirectional antenna are arranged at intervals along the direction of the zero point of the radiation pattern.

[0014] In one or more embodiments of this utility model, the radar module is located between the first omnidirectional antenna and the second omnidirectional antenna.

[0015] In one or more embodiments of the present invention, the first omnidirectional antenna includes a first low-profile antenna; and / or the second omnidirectional antenna includes a second low-profile antenna.

[0016] In one or more embodiments of this utility model, the radar module is connected to the first omnidirectional antenna via a microstrip line; and / or the radar module is connected to the second omnidirectional antenna via a microstrip line.

[0017] In one or more embodiments of the present invention, the radar sensor further includes a control module disposed on a substrate, the control module being connected to the radar module to control the radar module.

[0018] Compared with existing technologies, the radar sensor of this invention achieves 360-degree omnidirectional detection by employing a first omnidirectional antenna and a second omnidirectional antenna. Simultaneously, by aligning the maximum radiation directions of the first and second omnidirectional antennas in two different directions, coupling radiation between the two antennas is reduced, significantly improving the isolation between them, effectively reducing crosstalk, and enhancing detection stability and sensitivity. The use of a low-profile antenna results in a smaller size compared to traditional radar systems, making it easy to embed in various desktop small appliances. It can be integrated into PCB boards, reducing additional assembly steps and improving production efficiency and reliability. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a top view of a radar sensor in one embodiment of the present invention.

[0021] Figure 2 This is a system structure diagram of a radar sensor in one embodiment of the present invention.

[0022] Figure 3 This is a radiation pattern of the first omnidirectional antenna and the second omnidirectional antenna in one embodiment of the present invention.

[0023] Figure 4 This is an S-parameter diagram of the first omnidirectional antenna and the second omnidirectional antenna in one embodiment of the present invention.

[0024] Figure 5 This is an isolation diagram of the first omnidirectional antenna and the second omnidirectional antenna in one embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0026] The terms "coupled," "connected," or "linked" in this specification include both direct and indirect connections. Indirect connections are those made through an intermediate medium, such as those made through an electrically conductive medium, which may have parasitic inductance or capacitance. Indirect connections may also include connections made through other active or passive devices to achieve the same or similar functional purpose, such as connections through switches, follower circuits, or other circuits or components. Furthermore, in this specification, terms such as "first" and "second" are primarily used to distinguish one technical feature from another, and do not necessarily require or imply any actual relationship, quantity, or order between these technical features.

[0027] In the detailed description of this specification, reference is made to the accompanying drawings, which form a part thereof, wherein like reference numerals always denote like parts, and wherein exemplary embodiments are shown by way of example that may be implemented. It should be understood that other embodiments may be utilized, and structural or logical changes may be made, without departing from the scope of this application. Therefore, the following detailed description should not be considered limiting.

[0028] The various operations in the specification may be described sequentially as multiple discrete actions or operations in a manner most conducive to understanding the claimed subject matter. However, the order of description should not be construed as implying that these operations must be sequentially related. Specifically, these operations may not be performed in the order presented. The described operations may be performed in a different order than in the described embodiments. Various additional operations may be performed in additional embodiments and / or the described operations may be omitted.

[0029] For the purposes of this application, the phrase "A and / or B" means (A), (B), or (A and B). For the purposes of this application, the phrase "A, B and / or C" means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).

[0030] Various components and devices may be mentioned or shown in the singular form herein, but only for the convenience of discussion, and any element mentioned in the singular form may include multiple such elements as taught herein.

[0031] The description uses the phrases "in one embodiment," "in other embodiments," or "in some embodiments," each of which may refer to one or more of the same or different embodiments. Furthermore, the terms "comprising," "including," "having," etc., used in relation to embodiments of this application are synonymous.

[0032] like Figure 1 As shown, in one embodiment of the present invention, the radar sensor includes a substrate 10 and a first omnidirectional antenna 21, a second omnidirectional antenna 22 and a radar module 30 disposed on the substrate 10.

[0033] The radar module 30 is connected to the first omnidirectional antenna 21 and the second omnidirectional antenna 22 to control the first omnidirectional antenna 21 and the second omnidirectional antenna 22. The substrate 10 includes a first surface and a second surface facing away from each other. The maximum radiation direction of the first omnidirectional antenna 21 faces outward from the first surface, and the maximum radiation direction of the second omnidirectional antenna 22 faces outward from the second surface.

[0034] Specifically, an omnidirectional antenna refers to an antenna structure capable of transmitting or receiving signals in all directions within the far-field space at one or more operating frequencies. It not only achieves 360° coverage in the horizontal direction but also provides a certain degree of vertical sensing capability. This design enables 360° omnidirectional detection, overcoming the directional issues of most radar sensor antennas on the market. It is suitable for close-range 3D sensing applications in environments such as desktops and cylindrical devices, meeting the omnidirectional detection requirements of small desktop electronic devices.

[0035] Preferably, an omnidirectional antenna is selected that meets the following specifications: the difference between the maximum and minimum gain of the 360° transmit and receive combined pattern is less than 10dB.

[0036] In one embodiment, the first omnidirectional antenna 21 is a transmitting antenna, and the second omnidirectional antenna 22 is a receiving antenna. In other embodiments, the functions of the first omnidirectional antenna 21 and the second omnidirectional antenna 22 may be interchanged or other functions may be used.

[0037] In one embodiment, the first omnidirectional antenna 21 includes a first low-profile antenna. The first low-profile antenna may include one or more of a printed monopole antenna, a patch antenna, a microstrip antenna, a flexible PCB antenna, a PIFA antenna, and an IFA antenna. Preferably, the first low-profile antenna is a printed monopole antenna.

[0038] The second omnidirectional antenna 22 includes a second low-profile antenna. The second low-profile antenna may include one or more of the following: printed monopole antenna, patch antenna, microstrip antenna, flexible PCB antenna, PIFA antenna, and IFA antenna. Preferably, the second low-profile antenna is a printed monopole antenna.

[0039] The aforementioned low-profile antennas all refer to omnidirectional low-profile antennas, which can be designed and implemented using existing technologies.

[0040] By using a low-profile antenna instead of a traditional metal vibrator antenna, the antenna size is reduced, making it easier to integrate into small electrical devices. It also has the advantages of easy processing, high robustness, and the ability to be integrated with the substrate 10 for manufacturing, reducing additional assembly steps and improving production efficiency and reliability.

[0041] like Figure 1 As shown, with the positive z-axis as the top, in one embodiment, the upper surface of the substrate 10 is the first surface, and the lower surface of the substrate 10 is the second surface. The substrate 10 can be a PCB board. The maximum radiation direction of the first omnidirectional antenna 21 is upward (directly upward or obliquely upward), and the maximum radiation direction of the second omnidirectional antenna 22 is downward (directly downward or obliquely downward). By making the maximum radiation directions of the first omnidirectional antenna 21 and the second omnidirectional antenna 22 opposite to or staggered to each other, a higher degree of isolation is achieved.

[0042] Preferably, the maximum radiation direction of the first omnidirectional antenna 21 is opposite to the maximum radiation direction of the second omnidirectional antenna 22, that is, the angle between the two directions is 180°, so as to obtain the optimal isolation effect.

[0043] In one embodiment, a first omnidirectional antenna 21 is disposed on a first surface of a substrate 10, and a second omnidirectional antenna 22 is disposed on a second surface of a substrate 10, so that the maximum radiation direction of the first omnidirectional antenna 21 is directed toward the outside of the first surface of the substrate 10, and the maximum radiation direction of the second omnidirectional antenna 22 is directed toward the outside of the second surface of the substrate 10.

[0044] In one embodiment, the maximum radiation direction of the first omnidirectional antenna 21 and the maximum radiation direction of the second omnidirectional antenna 22 are perpendicular to the first surface of the substrate 10. That is, the maximum radiation direction of the first omnidirectional antenna 21 is perpendicular to the first surface of the substrate 10 and upward (along the positive z-axis direction), and the maximum radiation direction of the second omnidirectional antenna 22 is perpendicular to the second surface of the substrate 10 and downward (along the negative z-axis direction).

[0045] In other embodiments, the maximum radiation direction of the first omnidirectional antenna 21 and the maximum radiation direction of the second omnidirectional antenna 22 may also be perpendicular to the second surface of the substrate 10, or when the first surface and the second surface of the substrate 10 are parallel, the maximum radiation direction of the first omnidirectional antenna 21 and the maximum radiation direction of the second omnidirectional antenna 22 are simultaneously perpendicular to the two surfaces.

[0046] In one embodiment, the radiator (i.e., antenna patch) of the first omnidirectional antenna 21 is disposed on the first surface, and the radiator (i.e., antenna patch) of the second omnidirectional antenna 22 is disposed on the second surface. By attaching the radiators of the two antennas to the two sides of the substrate respectively, the maximum radiation direction of the transmitting and receiving antennas can be separated simply and effectively.

[0047] like Figure 1 As shown, the radar module 30 is connected to the first omnidirectional antenna 21 via a microstrip line, and the radar module 30 is also connected to the second omnidirectional antenna 22 via a microstrip line. By using a PCB microstrip line matching design between the RF structure of the radar module 30 and the two antennas, the stability of signal transmission and the reduction of signal loss are ensured.

[0048] Furthermore, the radiation pattern of the first omnidirectional antenna 21 is relative to the null point of the radiation pattern of the second omnidirectional antenna 22.

[0049] In one embodiment, the first omnidirectional antenna 21 and the second omnidirectional antenna 22 may be two identical antennas with the same radiation pattern.

[0050] Combination Figure 1 , Figure 2As shown, the null point (the direction of minimum radiation gain) of the radiation patterns of the first omnidirectional antenna 21 and the second omnidirectional antenna 22 is its electric field direction (i.e., the y-axis direction). In terms of layout, the electric field direction of the first omnidirectional antenna 21 is parallel to and opposite to the electric field direction of the second omnidirectional antenna 22, so that the "null point" of its minimum radiation gain points to the other antenna, thereby minimizing coupling.

[0051] Furthermore, the first omnidirectional antenna 21 and the second omnidirectional antenna 22 can be symmetrically arranged by flipping, that is, the second omnidirectional antenna 22 can be the first omnidirectional antenna 21 rotated 180° around the x-axis.

[0052] In other embodiments, two different first omnidirectional antennas 21 and second omnidirectional antennas 22 may also be used.

[0053] like Figure 1 As shown, the first omnidirectional antenna 21 and the second omnidirectional antenna 22 are spaced apart along the zero point direction of the radiation pattern (i.e., its electric field direction, y-axis). The coupling is further reduced by increasing the distance between the first omnidirectional antenna 21 and the second omnidirectional antenna 22.

[0054] The radar module 30 is located between the first omnidirectional antenna 21 and the second omnidirectional antenna 22. This facilitates the arrangement of transmission lines between the radar module 30 and the antennas. The length of the substrate 10 along the y-axis can be greater than its width along the x-axis. The substrate 10 can be rectangular, elongated cross-shaped, etc. The radar sensor is elongated, optimized for confined spaces, and suitable for use inside small appliances such as fan support columns, lamp posts, or desktop air purifiers and humidifiers. Compared to traditional millimeter-wave radar systems, it is more compact and easier to embed in various desktop devices.

[0055] like Figure 3 The figures shown are the S11 curve of the first omnidirectional antenna 21 and the S22 curve of the second omnidirectional antenna 22, respectively. Figure 4 The figure shows the isolation curve between the first omnidirectional antenna 21 and the second omnidirectional antenna 22. As can be seen from the figure, within the compliant frequency band of the 24GHz millimeter-wave radar, the radar sensor in this scheme exhibits good isolation performance.

[0056] like Figure 5 As shown, in one embodiment, the radar sensor may further include a control module 40, a power management module 50, and a communication interface 60. The control module 40, the power management module 50, and the communication interface 60 may also be disposed on the substrate 10.

[0057] The control module 40 is connected to the radar module 30 to control the radar module 30. The radar module 30 is preferably an S3KM111L millimeter-wave SoC, operating in the 24GHz or 60GHz frequency band. It can support 24GHz FMCW signal modulation, transmission, and reception, and has a built-in RF front-end, frequency synthesizer, ADC, and signal processing unit. It can output intermediate frequency signals, which are further processed by the control module 40 to achieve high-precision estimation of target distance, speed, and angle.

[0058] The control module 40 is preferably a GD32E230K8U6 or similar MCU chip, which can interact with the radar module 30 via SPI or UART to realize radar configuration management, radar data reception and preprocessing, and can have built-in algorithms to identify moving targets and static targets, and realize functions such as human presence, gesture recognition, and target tracking.

[0059] Through the collaborative work of radar module 30 and control module 40, radar module 30 can focus on the transmission, reception and preliminary processing of millimeter-wave signals, while control module 40 can be responsible for more complex data operations, identification algorithms, communication interface 60 management and power management, thus achieving a more efficient and flexible data processing architecture.

[0060] The communication interface 60 is used to connect to external devices. The control module 40 is connected to the communication interface 60 to communicate with external devices, and can send processed target information to the external main control system through the communication interface 60. The power management module 50 is connected to the communication interface 60 to obtain external power.

[0061] Communication interface 60 can be expanded to UART, SPI, I 2 C, CAN, or one or more of the following wireless communication methods (such as BLE and Wi-Fi).

[0062] The power management module 50 may include a power chip and a switching unit. The power chip is connected to the control module 40 and the switching unit. The power chip is used to generate the power supply voltage required by the control module 40 and the radar module 30 based on an external power supply. The power chip may adopt one or more power management types, such as LDO, DC-DC, AC-DC, and switching power supply.

[0063] The switching unit is connected to the radar module 30 to control the connection and disconnection between the radar module 30 and the power supply voltage based on its own on / off state. The control module 40 can be connected to the switching unit to control its on / off state. The switching unit can use a MOSFET switching circuit. The control module 40 is directly powered by a power chip, and then the control module 40 intelligently controls the power supply to the radar module 30, achieving independent power supply and power consumption control for the control module 40 and the radar module 30. This significantly reduces the overall power consumption and improves service life and reliability.

[0064] The radar sensor in this solution achieves 360-degree omnidirectional detection by employing a first omnidirectional antenna 21 and a second omnidirectional antenna 22. Simultaneously, by aligning the maximum radiation directions of the first omnidirectional antenna 21 and the second omnidirectional antenna 22 in two different directions, coupling radiation between the two antennas is reduced, significantly improving the isolation between them. This effectively reduces crosstalk between the antennas and enhances the stability and sensitivity of the detection. The use of low-profile antennas results in a smaller size compared to traditional radar systems, making them easier to embed in various desktop small appliances. They can be integrated into PCB boards during manufacturing, reducing additional assembly steps and improving production efficiency and reliability.

[0065] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0066] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A radar sensor, characterized by The device includes a substrate and a first omnidirectional antenna, a second omnidirectional antenna, and a radar module disposed on the substrate. The radar module is connected to the first omnidirectional antenna and the second omnidirectional antenna to control the first omnidirectional antenna and the second omnidirectional antenna. The substrate includes a first surface and a second surface disposed opposite to each other. The maximum radiation direction of the first omnidirectional antenna is directed towards the outside of the first surface, and the maximum radiation direction of the second omnidirectional antenna is directed towards the outside of the second surface.

2. The radar sensor of claim 1, wherein, The maximum radiation direction of the first omnidirectional antenna is opposite to that of the second omnidirectional antenna.

3. The radar sensor according to any one of claims 1 or 2, characterized in that, The maximum radiation direction of the first omnidirectional antenna and the maximum radiation direction of the second omnidirectional antenna are perpendicular to the first surface and / or the second surface.

4. The radar sensor of claim 1, wherein, The radiator of the first omnidirectional antenna is disposed on the first surface, and the radiator of the second omnidirectional antenna is disposed on the second surface.

5. The radar sensor of claim 1, wherein, The radiation pattern of the first omnidirectional antenna is opposite to the null point of the radiation pattern of the second omnidirectional antenna.

6. The radar sensor of claim 5, wherein, The first omnidirectional antenna and the second omnidirectional antenna are spaced apart along the zero point direction of the radiation pattern.

7. The radar sensor according to claim 1, characterized in that, The radar module is located between the first omnidirectional antenna and the second omnidirectional antenna.

8. The radar sensor of claim 1, wherein, The first omnidirectional antenna includes a first low-profile antenna; and / or The second omnidirectional antenna includes a second low-profile antenna.

9. The radar sensor of claim 1, wherein, The radar module is connected to the first omnidirectional antenna via a microstrip line; and / or The radar module is connected to the second omnidirectional antenna via a microstrip line.

10. The radar sensor of claim 1, wherein, The radar sensor also includes a control module mounted on a substrate, which is connected to the radar module to control the radar module.

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