A radio frequency radar sensing component device and system

Abstract

The present invention provides a radio frequency radar sensing component device and system. The radio frequency signal is transmitted through the Tx microstrip antenna in the FP antenna structure. After repeated reflection and signal enhancement by the internal spatial structure of the radio frequency resonant cavity, the radio frequency signal is transmitted to the detection area through the gaps in the microstrip structure array pattern on the metasurface beam conformal heterogeneous antenna carrier. After being reflected by a moving target in the detection area, the echo radiation signal is then transmitted through the gaps in the microstrip structure array pattern on the metasurface beam conformal heterogeneous antenna carrier to the Rx microstrip antenna, thereby acquiring the reflected signal of the moving target. After amplification and modulation, the intermediate frequency signal is output, which is then processed by the MCU for data processing and output of the corresponding trigger control signal. By combining two antenna structures of different material types, the radar transmission power of the radar PCBA board is reduced, the forward horizontal angle and vertical angle of the radar radio frequency signal transmission are compressed, the penetration rate of different dielectric bodies is improved, and the back and side radiation intensity and the induction false alarm rate of the radar PCBA board are significantly reduced.

Description

Technical Field

[0001] The present invention relates to the field of radar radio frequency technology, and in particular to a radio frequency radar sensing component device and system. Background Art

[0002] Compared with traditional human motion and presence sensing technologies, such as infrared reflection, pyroelectric infrared, and ultrasonic waves, microwave radar's high-frequency electromagnetic waves can effectively penetrate non-metallic materials such as ceramics, glass, and plastic. Although high-frequency loss and attenuation will occur depending on the material and thickness, these can be adjusted by adjusting the transmission line signal intensity and receiving sensitivity threshold. It is also unaffected by condensation and surface stains. Due to its small size, sensitive recognition, low susceptibility to environmental interference, and large amount of signal information, it has been widely used in the field of intelligent sensing and recognition, such as human motion, presence, and micro-motion recognition, and is used in automatic control, energy saving, and security monitoring. Common applications include smart toilets, bathroom mirror cabinet control, light switches, household appliance control, and security camera activation.

[0003] Radar radio frequency sensing technology uses the method of transmitting radio wave signals and receiving reflected signals for detection. It has gradually developed signal transmission methods such as CW (continuous wave), FMCW (frequency modulated continuous wave), and FSK (frequency shift keying). At the same time, the digital processing software technology for receiving signals is becoming increasingly sophisticated and has been put into practical application in Doppler signal processing, speed measurement, distance measurement, angle measurement, and micro-motion recognition.

[0004] To enable radar signals to penetrate non-shielded materials, such as composite wood, plastic, and glass-ceramics, to reach the required detection distance, or to detect micro-motion signals, such as those of the feet or hands, the conventional approach is to increase the antenna's RF transmission intensity to compensate for the attenuation caused by dielectric penetration and enhance the strength of micro-motion reflected signals. This approach, combined with appropriate signal processing software, can meet design requirements in laboratory environments. However, the complex spatial structures of actual operating environments make it difficult to predict the changes in RF signals due to transmission and reflection, leading to frequent failures such as false triggering (false alarms) and no sensing.

[0005] The front-lobe gain and irradiation angle of the electromagnetic wave emitted by RF radars are key technical controls for radar systems. Controlling the back-lobe and side-lobe strengths is essential for eliminating false alarms and improving stability. Due to cost constraints in smart home appliance radars, most conventional radars use rectangular microstrip antennas or array microstrip antennas. These front-lobe and back-lobe controls are largely uncontrolled, with only a makeshift approach of adjusting the trigger threshold to meet basic operational requirements. This can easily lead to problems such as self-excitation, false triggering, and unclear sensing control areas. Therefore, simply increasing the RF signal transmission intensity is not the optimal solution; specialized design is required for the intended application scenario. For example, enhanced processing can be performed on the transmitted signal to improve its directivity to control the recognition area; back- and side-radiation can be reduced to minimize false alarms; and the signal-to-noise ratio of the received signal can be improved to enhance micro-motion recognition. Overall, achieving the desired sensing trigger target conditions with a relatively appropriate transmit power under the intended operating conditions is one of the development trends in RF radar sensing component systems. Summary of the Invention

[0006] To address the aforementioned technical issues, the present invention proposes a radio frequency radar sensing component device and system. This device, which surrounds a cylindrical support structure, establishes a resonant cavity within the structure for proper RF radar wave transmission and repeated reflection, and a circular shielding ring composed of annular shielding material surrounding the structure. The RF signal emitted by the transmitting element on the radar PCBA is repeatedly reflected and amplified within the resonant cavity, ultimately radiating through the gaps between the passive antenna elements in the metasurface composite structure to the sensing area outside the component.

[0007] Specifically, the present invention provides a radio frequency radar sensing component device, comprising at least:

[0008] A closed cavity area is formed by a front cover, a shielding ring and a back cover, wherein an FP antenna structure is arranged in the closed cavity area, and the FP antenna structure includes:

[0009] Radar module installed on the PCBA board.

[0010] It is arranged on a metasurface beam conformal heterogeneous antenna carrier; the metasurface beam conformal heterogeneous antenna carrier is adhered to the front cover.

[0011] The PCBA board is arranged at one end of the shielding ring, and forms an internal space structure of the RF resonant mode cavity with the metasurface beam conformal heterogeneous antenna carrier; the other end of the shielding ring is nested in the edge groove of the outer ring of the front cover.

[0012] The radar module at least includes:

[0013] A radar driver chip is provided on one side of the PCBA board, and an Rx microstrip antenna and a Tx microstrip antenna are provided on the other side of the PCBA board and distributed on both sides of the corresponding position of the radar driver chip;

[0014] Furthermore, the radar module also includes: a high-resistance surface HIS structure, which is on the same surface of the PCBA board as the Rx microstrip antenna and the Tx microstrip antenna, and is distributed in a ring-shaped manner around the edge of the PCBA board.

[0015] The high-resistance surface HIS structure is specifically composed of a rectangular array and a slit channel distributed divergently from the inside to the outside, and the rectangular arrays are arranged in a staggered order of long and short; the high-resistance surface HIS structure is electrically connected to the PCBA board floor layer.

[0016] Among them, the metasurface beam conformal heterogeneous antenna carrier is an insulating material carrier with a specific dielectric constant; the microstrip patch array is composed of a metal micro-sheet pattern, and the metal micro-sheet pattern is a specific text and pattern structure arranged periodically according to a specific rule; the specific text and pattern are at least any one or more of characters, rectangles, circles and V-shapes; the pattern structure is at least any one or more of rectangles, fan-shaped arrays, Jerusalem shapes, and hexagonal patterns; the interval width of the specific text and pattern is set to between 0.2mm and 0.8mm.

[0017] Preferably, the distance between the PCBA board and the metasurface beam conformal heterogeneous antenna carrier board is 1 / 32 to 1 / 8 of the wavelength of the radio frequency signal.

[0018] Fixed buckles are respectively provided on both sides of the edge groove of the outer ring of the front cover; a through slot is opened at the position corresponding to the rear cover and the fixed buckle; the fixed buckle is detachably connected to the through slot to fix the shielding ring and the PCBA board.

[0019] Furthermore, the interior of the front cover is entirely encapsulated with a potting compound, such as polyurethane, silicone, or epoxy resin, forming a solid-state structure. This potting compound enhances the overall protection level, allowing for use in environments such as condensation, moisture, mildew, and flooding, improving reliability and extending service life.

[0020] The present invention provides a radio frequency sensing component system, which transmits a radio frequency signal through the Tx microstrip antenna in the FP antenna structure 4. After the radio frequency signal is repeatedly reflected and enhanced by the internal spatial structure of the radio frequency resonant mode cavity, it is transmitted to the detection area from the gap of the microstrip patch array on the metasurface beam conformal heterogeneous antenna carrier. After being reflected by the moving target in the detection area, the echo radiation signal is then transmitted to the Rx microstrip antenna through the pattern gap of the microstrip structure array on the metasurface beam conformal heterogeneous antenna carrier, thereby obtaining the reflected signal of the moving target. After amplification and modulation, the intermediate frequency signal is output, and the MCU performs data processing and outputs the corresponding trigger control signal.

[0021] In summary, the present invention provides a radio frequency radar sensing component device and system, comprising a radar PCBA comprising a microstrip antenna for transmitting and receiving radio frequency radar signals and a signal processing circuit; a conformal passive antenna element dielectric plate with a metasurface composite structure positioned in front of the radar microstrip antenna; a surrounding support structure, which spaced the two elements appropriately apart to form an internal space structure for a radio frequency resonant cavity; and a circular shielding ring composed of annular shielding material surrounding the outer surface. When the radio frequency signal emitted by the transmitting element on the radar PCBA is repeatedly reflected and amplified within the internal space of the resonant cavity, it is ultimately transmitted to the exterior of the component through the gaps between the antenna elements of the metasurface composite structure. When the reflected wave penetrates non-metallic dielectric materials such as ceramics, plastics, and wood composite panels and is reflected by a moving human body / object, it carries a reflected modulated signal with a superimposed Doppler frequency, penetrates the passive antenna vibrator array on the dielectric board, that is, the gap in the microstrip structure array pattern on the metasurface beam conformal heterogeneous antenna carrier board, and reaches the microstrip receiving antenna on the radar PCBA board. The received RF signal is amplified and modulated, and output as an intermediate frequency signal. The MCU performs data processing and outputs a trigger control signal for the actuator to operate.

[0022] This invention, through the design of two different antenna structures, reduces the radar PCBA's radar transmission power, compresses the forward horizontal and vertical angles of the radar RF signal, improves penetration into various dielectric materials, and significantly reduces the PCBA's back- and side-radiation intensity and false alarm rate. The compact, fully sealed RF components and system are suitable for long-term, stable operation in humid and even submerged environments, such as smart toilets, faucets, and security monitoring systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a radio frequency radar sensing component device described in the present invention.

[0024] Figure 2 For example Figure 1 A side view of a radio frequency radar sensing component device.

[0025] Figure 3 For example Figure 1 Schematic diagram of the radar module.

[0026] Figure 4 For example Figure 1 Schematic diagram of the metasurface beam conformal heterogeneous antenna carrier.

[0027] Among them, 1-front cover; 11-edge groove; 12-fixing buckle; 13-antenna positioning column; 2-shielding ring; 3-back cover; 31-through slot; 4-FP antenna structure; 41-PCBA board; 42-radar module; 421-radar driver chip; 422-Rx microstrip antenna; 423-Tx microstrip antenna; 424-high resistance surface HIS structure; 43-metasurface beam conformal heterogeneous antenna carrier board; 44-microstrip structure array pattern; 45-positioning hole; 5-power controller; 6-power controller outlet; 7-fixing hole. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0029] like Figure 1-2 As shown, the radio frequency radar sensing component device of the present invention comprises at least: a closed cavity area composed of a front cover 1, a shielding ring 2 and a rear cover 3, wherein an FP antenna structure 4 is arranged in the closed cavity area, and the FP antenna structure 4 comprises:

[0030] A radar module 42 is provided on a PCBA board 41;

[0031] A microstrip structure array pattern 44 is provided on a metasurface beam conformal heterogeneous antenna carrier 43; the metasurface beam conformal heterogeneous antenna carrier 43 is bonded to the front cover 1;

[0032] The PCBA board 41 is arranged at one end of the shielding ring 2, and forms the internal space structure of the RF resonant mode cavity with the metasurface beam conformal heterogeneous antenna carrier 43; the other end of the shielding ring 2 is nested in the outer edge groove 11 of the front cover 1.

[0033] By forwardly superimposing high gain on the FP antenna structure 4, the gain of the generated signal can be increased and the directivity of the front lobe can be adjusted.

[0034] The radar module 42 at least includes:

[0035] like Figure 3 As shown, a radar driving chip 421 is arranged on one side of the PCBA board 41, and an Rx microstrip antenna 422 and a Tx microstrip antenna 423 are arranged on the other side of the PCBA board 41 and distributed on both sides of the corresponding position of the radar driving chip 421.

[0036] A high-resistance surface (HIS) structure 424 is disposed around the edge of the PCBA board 41 on the side where the Rx microstrip antenna 422 and Tx microstrip antenna 423 are located. Preferably, the PCBA board 41 is circular, and the high-resistance surface (HIS) structure 424 surrounds the circular perimeter of the PCBA board 41, enclosing the Rx microstrip antenna 422 and Tx microstrip antenna 423 within the center of the PCBA board 41. Preferably, the PCBA board 41 is circular, and the high-resistance surface (HIS) structure 424 can also be other shapes, such as, but not limited to, a square. Similarly, the high-resistance surface (HIS) structure 424 is also distributed around the outer edge of the PCBA board 41.

[0037] Preferably, the high-resistance surface HIS structure 424 is specifically composed of a rectangular array and slit channels distributed divergently from the inside to the outside, and the rectangular arrays are arranged in a staggered order of length; the high-resistance surface HIS structure 424 is electrically connected to the floor layer of the PCBA board 41.

[0038] Among them, the high-resistance surface HIS structure 424 set up in the present invention can suppress the flow of current on the surface of the conductor, so that the surface current near the surface of the conductor decays rapidly, thereby reducing edge diffraction and the backward radiation loss caused by it, and can significantly suppress the back lobe of the FP antenna and improve the forward gain.

[0039] The present invention utilizes a microstrip antenna structure with an HIS layer arranged around the antenna perimeter. A metasurface beam conformal heterogeneous antenna carrier 43 is mounted at the antenna's front end, forming an FP antenna structure with the radar PCBA floor layer. The perimeter is enclosed with stainless steel and encapsulated within a plastic housing, forming the enhanced resonant cavity and variable gain and directional RF sensing component system of the electromagnetic metasurface combined structure. Furthermore, the present invention utilizes the 10G band within the 8-12 GHz X-band, an ideal frequency band for sensing radars. This avoids cellular communication interference while offering better penetration than millimeter waves, making it suitable for applications in smart home products and other applications.

[0040] The metasurface beam conformal heterogeneous antenna carrier 43 is an insulating material carrier with a specific dielectric constant; the microstrip structure array pattern 44 is composed of a metal micro-sheet pattern, and the metal micro-sheet pattern is a specific text and pattern structure arranged periodically according to a specific rule; the specific text and pattern are at least any one or more of characters, rectangles, circles and V-shapes; the pattern structure is at least any one or more of rectangles, fan-shaped arrays, Jerusalem shapes, and hexagonal patterns; the interval width of the specific text and pattern is set to between 0.2mm and 0.8mm.

[0041] like Figure 4 As shown, the metal micro-sheet pattern on the metasurface beam conformal heterogeneous antenna carrier 43 is preferably composed of a periodic arrangement of subwavelength microstructure units, allowing the irradiation direction of the electromagnetic wave to be perpendicular to the material plane. The electromagnetic metasurface has properties similar to those of an ideal magnetic conductor, enabling plane waves to be reflected in phase within a specific frequency range. Furthermore, the amplitude, phase, polarization, and propagation mode of the electromagnetic wave can be flexibly and effectively controlled, thereby effectively improving the performance of the microstrip structure array pattern 44, reducing the radar cross section and microwave transmission performance.

[0042] Preferably, the distance between the PCBA board 41 and the metasurface beam conformal heterogeneous antenna carrier board 43 is 1 / 32 to 1 / 8 of the wavelength of the radio frequency signal.

[0043] Preferably, the shielding ring 2 is made of corrosion-resistant shielding material with a wall thickness of 0.1-1.0 mm.

[0044] Preferably, fixing buckles 12 are respectively provided on both sides of the outer edge groove of the front cover 1; a through slot 31 is opened at the corresponding position of the rear cover 3 and the fixing buckle 12; the fixing buckle 12 and the through slot 31 are detachably connected to fix the shielding ring 2 and the PCBA board 41.

[0045] An antenna positioning post 13 is provided on the front cover 1 , and a positioning hole 45 is set at the position of the metasurface beam conformal heterogeneous antenna carrier 43 corresponding to the positioning post 13 , and the metasurface beam conformal heterogeneous antenna carrier 43 is fixed to the front cover 1 by hot pressing.

[0046] The interior of the front cover is encapsulated as a whole with potting glue to form an overall solid structure. The potting glue includes polyurethane, silicone, and epoxy resin. Preferably, silicone potting glue with low dielectric constant (<3.0), low high-frequency loss, and low water absorption is used.

[0047] For ease of use, power and control signal line outlets are optionally provided on the rear cover 3 to extend the power controller out of the rear cover 3. Fixing holes 7 are provided on the front cover to form a "glue nail" structure when installing by bonding, thereby improving bonding reliability.

[0048] As another preferred embodiment, the present invention also provides a radio frequency sensing component system, which transmits a radio frequency signal through the Tx microstrip antenna 423 in the FP antenna structure 4. After the radio frequency signal is repeatedly reflected and the signal is enhanced by the internal space structure of the radio frequency resonant mode cavity, it is transmitted to the detection area from the gap of the microstrip structure array pattern 44 on the metasurface beam conformal heterogeneous antenna carrier 43. After being reflected by the moving target in the detection area, the echo radiation signal is then transmitted to the Rx microstrip antenna 422 through the gap of the microstrip structure array pattern on the metasurface beam conformal heterogeneous antenna carrier, thereby obtaining the reflected signal of the moving target, and after amplification and modulation, the intermediate frequency signal is output, and the MCU performs data processing and outputs the corresponding trigger control signal.

[0049] In another embodiment, a specific implementation case of the present invention is the design and implementation of a toilet foot-sensing radar switch, which is installed on the lower part of the inner wall of the ceramic toilet support body and is controlled by foot movement. The human hand does not need to touch the toilet cover or seat ring to complete actions such as flipping the lid and flushing. This is beneficial to improving the user experience and avoiding cross-infection hygiene problems caused by hand contact. Smart toilets have a small internal space and a compact structural layout. Metal materials and rotating motor actuators are used more frequently. The electromagnetic environment is complex. There are water mist, condensation, temperature transients, etc. during use. Simple transmitting and receiving radar methods are difficult to apply. The present invention adopts an FP antenna structure to achieve sharp and reliable radar sensing with a relatively low transmission power, comprehensively suppressing back and side lobes, and significantly reducing false alarms.

[0050] This invention, through the design of two different types of antenna structures, reduces the radar transmit power of the radar PCBA board, compresses the forward horizontal and vertical angles of the radar RF signal transmission, improves the penetration rate into different dielectric bodies, and significantly reduces the back and side radiation intensity and the false alarm rate of the radar PCBA board. The RF components and system of this invention are compact and fully sealed, making them suitable for long-term stable operation in humid and even submerged environments such as smart toilets, faucets, and security monitoring systems.

[0051] In addition, the functional modules in the various embodiments of the present invention may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0052] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0053] The above-described embodiment merely represents one embodiment of the present invention. While the description is relatively specific and detailed, it should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A radio frequency radar sensing component device, characterized in that: At least: A closed cavity area is formed by a front cover (1), a shielding ring (2) and a rear cover (3), wherein an FP antenna structure (4) is arranged in the closed cavity area, and the FP antenna structure (4) includes: A radar module (42) disposed on a PCBA board (41); A microstrip structure array pattern (44) is provided on a metasurface beam conformal heterogeneous antenna carrier (43); the metasurface beam conformal heterogeneous antenna carrier (43) is bonded to the front cover (1); The PCBA board (41) is arranged at one end of the shielding ring (2) and forms an internal space structure of the radio frequency resonance mode cavity with the metasurface beam conformal heterogeneous antenna carrier board (43); The other end of the shielding ring (2) is nested in the outer ring edge groove (11) of the front cover (1); The radar module (42) includes: a high-resistance surface HIS structure (424), wherein the high-resistance surface HIS structure (424) is specifically composed of a rectangular array and slot channels that are distributed in a divergent manner from inside to outside, and the rectangular arrays are arranged in a staggered order of length; the high-resistance surface HIS structure (424) is electrically connected to the floor layer of the PCBA board (41); The distance between the PCBA board (41) and the metasurface beam conformal heterogeneous antenna carrier board (43) is 1 / 32 to 1 / 8 of the wavelength of the radio frequency signal; The shielding ring (2) is made of corrosion-resistant shielding material and has a wall thickness of 0.1-1.0 mm.

2. The radio frequency radar sensing component device according to claim 1, characterized in that: The radar module (42) comprises at least: a radar driving chip (421) arranged on one side of the PCBA board (41), and an Rx microstrip antenna (422) and a Tx microstrip antenna (423) arranged on the other side of the PCBA board (41) and distributed on both sides of a corresponding position of the radar driving chip (421).

3. The radio frequency radar sensing component device according to claim 2, characterized in that: The radar module (42) further includes a high-resistance surface HIS structure (424), wherein the high-resistance surface HIS structure (424) and the Rx microstrip antenna (422) and the Tx microstrip antenna (423) are on the same surface of the PCBA board (41), and are distributed in a ring-shaped surrounding manner around the edge of the PCBA board (41).

4. The radio frequency radar sensing component device according to claim 3, characterized in that: The metasurface beam conformal heterogeneous antenna carrier (43) is an insulating material carrier with a specific dielectric constant; the microstrip structure array pattern (44) is composed of a metal micro-sheet pattern, and the metal micro-sheet pattern is a specific text and pattern structure arranged periodically according to a specific rule; the specific text and pattern are at least any one or more of characters, rectangles, circles and V-shapes; the pattern structure is at least any one or more of rectangles, fan-shaped arrays, Jerusalem shapes and hexagonal patterns; the interval width of the specific text and pattern is set to between 0.2 mm and 0.8 mm.

5. The radio frequency radar sensing component device according to claim 4, characterized in that: Also includes: Fixing buckles (12) are respectively provided on both sides of the outer edge groove of the front cover (1); a through slot (31) is provided on the rear cover (3) at a position corresponding to the fixing buckle (12); the fixing buckle (12) and the through slot (31) are detachably connected to fix the shielding ring (2) and the PCBA board (41).

6. The radio frequency radar sensing component device according to claim 5, characterized in that: Also includes: The interior of the front cover (1) is encapsulated as a whole by potting glue to form an overall solid structure. The potting glue includes polyurethane, silicone, and epoxy resin.

7. A system of radio frequency radar sensing components according to any one of claims 1 to 6, characterized in that: include: A radio frequency signal is transmitted through the Tx microstrip antenna (423) in the FP antenna structure (4). After the radio frequency signal is repeatedly reflected and the signal is enhanced by the internal space structure of the radio frequency resonant cavity, it is transmitted to the detection area from the gap of the microstrip structure array pattern (44) on the metasurface beam conformal heterogeneous antenna carrier (43). After being reflected by the moving target in the detection area, the echo radiation signal is transmitted to the Rx microstrip antenna (422) through the gap of the microstrip structure array pattern on the metasurface beam conformal heterogeneous antenna carrier to obtain the reflected signal of the moving target. After amplification and modulation, the intermediate frequency signal is output, and the MCU performs data processing and outputs the corresponding trigger control signal.

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