Millimeter wave radar monitoring range constraint device
By setting up a beam constraint structure made of wave absorbing material next to the millimeter-wave radar antenna structure, the electromagnetic beam is narrowed by using the wave limiting hole to solve the problem of low signal-to-noise ratio of radar signals in a noise environment, and a low-cost and efficient beam narrowing effect is achieved.
Patent Information
- Application Number
- CN202421319911.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-11
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-06-11
AI Technical Summary
When monitoring human vital sign signals, weak signals are easily affected by environmental noise, resulting in low signal-to-noise ratio. In general methods, narrowing the beam width requires larger antennas or multiple inputs and multiple output radars, which is costly.
A millimeter wave radar monitoring range constraint device is designed. By setting a beam constraint structure made of wave absorbing material next to the millimeter wave radar antenna structure, the electromagnetic beam is narrowed by using a wave limiting hole to achieve constraints on the electromagnetic wave range.
Without changing the original radar antenna design, the manufacturing cost is effectively reduced, the signal-to-noise ratio is improved, the narrowing effect of the electromagnetic beam is enhanced, and the monitoring accuracy of the target area of the human body is improved.
Smart Images
Figure CN222994656U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of radar signal processing and biomedical engineering processing technology, and in particular to a millimeter wave radar monitoring range constraint device. Background Art
[0002] By receiving electromagnetic waves reflected by the human body, millimeter-wave radar can detect the vital signs of the human body without contacting the human body. It is very suitable for continuously monitoring the vital signs of human targets at night.
[0003] Since breathing and heartbeat signals are weak signals and are easily affected by environmental noise, it is necessary to increase the signal-to-noise ratio within the human target area as much as possible and reduce the echo energy outside the area (where interference sources may appear). This requires the beam width of the millimeter-wave radar to be as narrow as possible, but the ordinary narrow beam width solution requires a larger antenna physical size or a multiple-input multiple-output radar solution, which brings higher costs. Utility Model Content
[0004] The purpose of this application is to provide a millimeter-wave radar monitoring range constraint device, which proposes a low-cost method that does not change the original radar antenna design and achieves the effect of narrowing the beam width.
[0005] Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.
[0006] According to a first aspect of the present application, a millimeter wave radar monitoring range constraint device is provided, comprising:
[0007] Millimeter wave radar antenna structure for transmitting and receiving electromagnetic waves;
[0008] A beam constraining structure is configured to constrain transmitted and / or received electromagnetic waves. The beam constraining structure is disposed on a side adjacent to the millimeter wave radar antenna structure for transmitting and receiving the electromagnetic waves. The beam constraining structure is penetrated by a wave-limiting hole for the electromagnetic waves to pass through.
[0009] In an exemplary embodiment of the present application, the beam-constraining structure is a structure made of absorbing material.
[0010] In an exemplary embodiment of the present application, the distance from the millimeter wave radar antenna structure to the beam constraining structure is 0-50 mm.
[0011] In an exemplary embodiment of the present application, an outer shell is also included, and the millimeter wave radar antenna structure and the beam constraint structure are both fixed inside the outer shell.
[0012] In an exemplary embodiment of the present application, a fixture for fixing the beam constraint structure is disposed inside the outer housing. The fixture is fixedly connected to the outer housing. The beam constraint structure is placed inside the fixture. The circumferential inner wall of the fixture abuts against the circumferential outer wall of the beam constraint structure. A support plate is fixedly provided on a side of the fixture close to the millimeter-wave radar antenna structure. An end face of the beam constraint structure close to the millimeter-wave radar antenna structure abuts against the support plate.
[0013] In an exemplary embodiment of the present application, the fixture is a cylindrical structure, and an outer wall of the beam constraint structure is a cylindrical surface matching an inner wall of the cylindrical structure.
[0014] In an exemplary embodiment of the present application, the millimeter-wave radar antenna structure includes a radar chip. An antenna assembly capable of transmitting and receiving electromagnetic waves is provided on a surface of the radar chip. The antenna assembly includes at least one receiving antenna for receiving the electromagnetic waves and at least one transmitting antenna for transmitting electromagnetic waves. A center of the radar chip is aligned with a center of the wave-limiting hole.
[0015] In an exemplary embodiment of the present application, a cross-section of the wave-limiting hole is circular. A center of the wave-limiting hole and a center of the radar chip are located on the same axis. A formula for calculating a radius R1 of the wave-limiting hole is:
[0016]
[0017] where is half of a detection angle of the radar chip, H0 is a distance from the radar chip to an end of the wave-limiting hole far from the radar chip, L1 is a maximum antenna edge distance of the antenna assembly in the x direction; x is a horizontal coordinate axis of a plane where the radar chip has the antenna assembly on its surface.
[0018] In an exemplary embodiment of the present application, a cross-section of the wave-limiting hole is circular. A center of the wave-limiting hole and a center of the radar chip are located on the same axis. A formula for calculating a radius R2 of the wave-limiting hole is:
[0019]
[0020] where is half of a detection angle of the radar chip, H0 is a distance from the radar chip to an end of the wave-limiting hole far from the radar chip, L2 is a maximum antenna edge distance of the antenna assembly in the y direction; y is a vertical coordinate axis of a plane where the radar chip has the antenna assembly on its surface.
[0021] In an exemplary embodiment of the present application, the millimeter-wave radar antenna structure further includes a circuit board, on which the radar chip is installed, and the circuit board is used for circuit conduction and positioning of the lightning chip.
[0022] The exemplary embodiments of the present application may have some or all of the following beneficial effects:
[0023] 1. In a millimeter-wave radar monitoring range constraint device provided by the exemplary embodiment of the present application, by drilling a wave-limiting hole through the middle of the beam constraint structure and placing the beam constraint structure in front of the radar chip, the radar chip can emit and receive electromagnetic waves through the wave-limiting hole, while the beam constraint structure can absorb electromagnetic waves outside the wave-limiting hole. Thus, through this structure, without changing the original antenna design of the radar chip, the effect of constraining the electromagnetic wave range can be achieved, and the manufacturing cost can be effectively reduced.
[0024] 2. In a millimeter-wave radar monitoring range constraint device provided by the exemplary embodiment of the present application, the fixture has a good reinforcement effect on the beam constraint structure, enabling the device to have good stability during use;
[0025] 3. In a millimeter-wave radar monitoring range constraint device provided by the exemplary embodiment of the present application, by processing the wave-limiting hole at the center of the beam constraint structure, the absorption effect of electromagnetic waves in all directions can be made the same, so as to ensure good absorption effect on electromagnetic waves in all directions;
[0026] 4. In a millimeter-wave radar monitoring range constraint device provided by the exemplary embodiment of the present application, according to the actual use requirements, if it is necessary to constrain the range of the vertical distance as much as possible in the actual application scenario, then the radius R2 calculated according to the vertical distance is used as the radius of the wave-limiting hole for drilling, and the same applies to the horizontal direction.
[0027] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and those of ordinary skill in the art can obtain other drawings without creative efforts based on these drawings.
[0029] Figure 1 Shows the external structural schematic diagram of a millimeter-wave radar monitoring range constraint device in an embodiment of the present application;
[0030] Figure 2 The figure shows a schematic internal structure diagram of a millimeter-wave radar monitoring range constraint device in an embodiment of the present application;
[0031] Figure 3 The figure shows a schematic structure diagram of the notch radius and the radar chip in an embodiment of the present application.
[0032] Explanation of reference numerals:
[0033] 1. Beam constraint structure; 11. Notch; 2. Fixture; 21. Support plate; 3. Millimeter-wave radar antenna structure; 31. Radar chip; 32. Circuit board; 4. Outer housing. Detailed implementation manners
[0034] Now, example embodiments will be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the figures denote the same or similar structures, and thus their detailed descriptions will be omitted. In addition, the drawings are only schematic illustrations of the present application and are not necessarily drawn to scale.
[0035] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the icon to another component, these terms are used in this specification only for convenience, for example, according to the orientation of the example in the drawings. It can be understood that if the device of the icon is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" another structure, it may mean that a structure is integrally formed on another structure, or that a structure is "directly" disposed on another structure, or that a structure is "indirectly" disposed on another structure through another structure.
[0036] The terms "a", "an", "the" and "at least one" are used to indicate the existence of one or more elements / components / etc.; the terms "comprising" and "having" are used to mean an open inclusion and mean that there may be additional elements / components / etc. in addition to the listed elements / components / etc.; the terms "first" and "second" are used only as labels and are not a limitation on the quantity of their objects.
[0037] Referring to Figure 1 and Figure 2 , a millimeter-wave radar monitoring range constraint device includes:
[0038] A millimeter-wave radar antenna structure 3 for transmitting and receiving electromagnetic waves;
[0039] The beam constraint structure 1 is configured to absorb the electromagnetic wave. The beam constraint structure 1 is disposed on one side adjacent to the millimeter-wave radar antenna structure 3 for transmitting and receiving the electromagnetic wave. The beam constraint structure 1 is provided with a wave-limiting hole 11 through which the electromagnetic wave passes.
[0040] In practical applications, the millimeter-wave radar antenna structure 3 emits electromagnetic waves with a relatively wide area, and only part of the electromagnetic waves can pass through the wave-limiting hole 11, and the rest of the electromagnetic waves are absorbed by the beam constraint structure 1, thereby realizing the narrowing of the electromagnetic wave. This structure does not need to change the original millimeter-wave radar antenna structure 3. Thus, the precise narrowing of the electromagnetic beam is achieved in an economical and efficient manner.
[0041] Furthermore, in the embodiment of the present application, the beam constraint structure 1 is a structure made of an electromagnetic wave absorbing material, such as materials like absorbing sponges, etc., to achieve a good effect of electromagnetic wave absorption and constraint; it should be noted that the material selection is not limited to the above, and various materials can also be adopted for the electromagnetic wave absorbing material. As for the morphological design, there is no special limitation either. It can be cylindrical, or it can also be horn-shaped, square, irregular, etc.
[0042] In the embodiment of the present application, the distance between the millimeter-wave radar antenna structure 3 and the beam constraint structure 1 is 0 - 50 mm. In the embodiment of the present application, the distance between the millimeter-wave radar antenna structure 3 and the beam constraint structure 1 is preferably set to 2 mm. The distance of 2 mm can effectively prevent the millimeter-wave radar antenna structure 3 from overheating and causing the absorbing material to be deformed by heat, and at the same time, it minimizes the space between the two as much as possible to minimize the volume of the device.
[0043] In the embodiment of the present application, the millimeter-wave radar monitoring range constraint device further includes a housing 4. The top cover part of the housing 4 can be made of ABS plastic. The selection of this material is aimed at ensuring the smooth penetration of electromagnetic waves, taking into account both practicality and cost. Both the millimeter-wave radar antenna structure 3 and the beam constraint structure 1 are fixedly arranged inside the housing 4. The millimeter-wave radar antenna structure 3 is located on the side of the beam constraint structure 1 away from the top cover part of the housing 4. The fixing methods of the two to the housing 4 are not restrictive. For example, methods such as pasting, clamping, and bolt connection are all acceptable.
[0044] As a preferred embodiment in the present application document, in order to facilitate the installation of the beam constraint structure 1, a fixture 2 is provided inside the housing 4. One side of the fixture 2 away from the millimeter-wave radar antenna structure 3 is fixedly connected to the inner wall of the top cover part of the housing 4. On the side of the fixture 2 close to the millimeter-wave radar antenna structure 3, a support plate 21 is fixedly provided towards the inner side of itself. The number of the support plates 21 is not restrictive. In the embodiment of the present application, four support plates 21 are provided, and the four support plates 21 are evenly distributed around the circumferential inner wall of the fixture 2.
[0045] Place the wave-limiting structure inside the fixture 2, so that the circumferential inner wall of the fixture 2 fits seamlessly with the outer peripheral contour of the wave-limiting structure, achieving precise matching. The support plate 21 abuts against the bottom of the wave-limiting structure to form a stable support point for supporting the wave-limiting structure. This structure not only effectively prevents any slippage of the wave-limiting structure inside, but also significantly enhances its positioning stability within the outer housing 4, thereby improving the reliability and precision of the overall structure.
[0046] Specifically, in the embodiment of the present application, the fixture 2 is cylindrical, and the outer wall of the beam constraint structure 1 is a cylindrical curved surface that matches the inner wall of the cylindrical structure.
[0047] In the embodiment of the present application, the millimeter-wave radar antenna structure 3 includes a radar chip 31 and a circuit board 32. The surface of the radar chip 31 has an antenna assembly capable of transmitting and receiving electromagnetic waves; the radar chip 31 is installed on the circuit board 32, and the circuit board 32 is used for circuit conduction and positioning of the radar chip 31; the circuit board 32 is fixedly connected inside the outer housing 4, and the fixing method is not limited. The four corners of the circuit board 32 can be connected and fixed to the outer housing 4 by means of bolt connection.
[0048] As a preferred embodiment of the present application, the wave-limiting hole 11 is a circular hole. Of course, the shape of the wave-limiting hole 11 is not restrictive. In other embodiments, the wave-limiting hole 11 can also be a square hole, a triangular hole, or an irregular hole.
[0049] Furthermore, in order to ensure the uniformity of transmitting and receiving electromagnetic waves by the radar chip 31 in all directions, the center of the radar chip 31 is aligned with the center of the limiting hole. Of course, this is not restrictive, and any point on the radar chip 31 can be aligned with the center of the wave-limiting hole 11.
[0050] Refer to Figure 2 and Figure 3 , the antenna assembly includes at least one receiving antenna for receiving the electromagnetic wave and at least one transmitting antenna for transmitting the electromagnetic wave. When the cross-section of the wave-limiting hole 11 is circular and the center of the wave-limiting hole 11 and the center of the radar chip 31 are on the same axis, the formula for calculating the radius R of the wave-limiting hole 11 is:
[0051]
[0052] Among them, is half of the detection angle of the radar chip 31, H0 is the distance from the radar chip 31 to the end of the wave-limiting hole 11 far from the radar chip 31 (i.e., the distance from the radar chip 31 to the beam constraint structure 1 plus the thickness of the beam constraint structure 1), L is the maximum antenna edge distance of the antenna assembly in the x or y direction; x and y are the horizontal coordinate axis and the vertical coordinate axis of the plane where the surface of the radar chip 31 with the antenna assembly is located, respectively.
[0053] In the embodiment of the present application, the antenna assembly includes three receiving antennas for receiving electromagnetic waves and one transmitting antenna for transmitting electromagnetic waves. The three receiving antennas are Rx1, Rx2, and Rx3 respectively; the transmitting antenna is Tx. The transmitting antenna and one of the receiving antennas are symmetrically distributed along a central line of the radar chip 31 in the horizontal coordinate direction. In this application document, taking the structure formed by Tx and Rx2 as an example, the distance between them is L1; two of the receiving antennas are symmetrically distributed along another center of the radar chip 31 in the vertical coordinate direction. In this application document, taking the structure formed by Rx2 and Rx3 as an example, the distance between them is L2, and L1 should be greater than the distance between Rx1 and Rx3. Of course, the structure of the antenna assembly is not limited to this.
[0054] Taking the center of the radar chip 31 as the base point, the base point is aligned with the center of the limiting hole, and the straight line where they are located is the reference line.
[0055] The intersection point of the reverse extension lines of the detection range edges of Tx and Rx2 and the reference line is the first focus, and the distance from the first focus to the radar chip 31 is H1. The formula for calculating H1 is
[0056]
[0057] Among them, when using the length of L1 to constrain the detection range of the radar chip 31, the calculation method of the radius of the wave-limiting hole 11 is
[0058]
[0059] The intersection point of the reverse extension lines of the detection range edges of Rx2 and Rx3 and the reference line is the second focus, and the distance from the second focus to the radar chip 31 is H2. The formula for calculating H2 is
[0060]
[0061] Among them, when using the length of L2 to constrain the detection range of the radar chip 31, the calculation method of the radius of the wave-limiting hole 11 is
[0062]
[0063] When processing the wave-limiting holes 11 of the beam constraint structure 1, either R1 or R2 can be used as the processing parameter for the radius of the wave-limiting holes 11. This is mainly determined according to the actual usage situation. In actual use, mainly for the horizontal and vertical distances, the calculated aperture sizes are different. If it is necessary to minimize the range of the horizontal distance in the actual application scenario, then the holes are dug according to the aperture calculated from the horizontal distance (i.e., using R1 as the radius of the wave-limiting holes 11). If it is necessary to minimize the range of the vertical distance in the actual application scenario, then the holes are dug according to the aperture calculated from the vertical distance (i.e., using R2 as the radius of the wave-limiting holes 11).
[0064] After considering the specification and practicing the embodiments of the present application, those skilled in the art will readily conceive of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of the present application and include known common knowledge or conventional technical means in the technical field not claimed in the present application. The specification and embodiments are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the appended claims.
Claims
1. A millimeter wave radar monitoring range constraint device, characterized in that: include: A millimeter wave radar antenna structure (3) for transmitting and receiving electromagnetic waves; A beam-constraining structure (1) is configured to constrain transmitted and / or received electromagnetic waves, the beam-constraining structure (1) being disposed on a side adjacent to the millimeter-wave radar antenna structure (3) for transmitting and receiving the electromagnetic waves, and the beam-constraining structure (1) is provided with a wave-limiting hole (11) through which the electromagnetic waves pass.
2. A millimeter wave radar monitoring range constraint device according to claim 1, characterized in that: The beam-constraining structure (1) is a structure made of wave-absorbing material.
3. The millimeter wave radar monitoring range constraint device according to claim 1, characterized in that: The distance between the millimeter wave radar antenna structure (3) and the beam constraint structure (1) is 0-50 mm.
4. The millimeter wave radar monitoring range constraint device according to claim 1, characterized in that: It also comprises an outer shell (4), wherein the millimeter wave radar antenna structure (3) and the beam constraint structure (1) are both fixed inside the outer shell (4).
5. The millimeter wave radar monitoring range constraint device according to claim 4, characterized in that: A fixture (2) for fixing the beam constraint structure (1) is arranged inside the outer shell (4); the fixture (2) is fixedly connected to the outer shell (4); the beam constraint structure (1) is placed inside the fixture (2); the circumferential inner wall of the fixture (2) abuts against the circumferential outer wall of the beam constraint structure (1); a support plate (21) is fixedly arranged on the side of the fixture (2) close to the millimeter-wave radar antenna structure (3); and the end face of the beam constraint structure (1) close to the millimeter-wave radar antenna structure (3) abuts against the support plate (21).
6. The millimeter wave radar monitoring range constraint device according to claim 5, characterized in that: The fixture (2) is a cylindrical structure, and the outer wall of the beam-constraining structure (1) is a cylindrical curved surface that matches the inner wall of the cylindrical structure.
7. A millimeter wave radar monitoring range constraint device according to any one of claims 1 to 6, characterized in that: The millimeter wave radar antenna structure (3) comprises a radar chip (31), the surface of the radar chip (31) has an antenna component capable of transmitting and receiving electromagnetic waves, the antenna component comprises at least one receiving antenna for receiving the electromagnetic waves and at least one transmitting antenna for transmitting electromagnetic waves, and the center of the radar chip (31) is aligned with the center of the wave limiting hole (11).
8. The millimeter wave radar monitoring range constraint device according to claim 7, characterized in that: The cross section of the wave limiting hole (11) is circular, the center of the wave limiting hole (11) and the center of the radar chip (31) are located on the same axis, and the formula for calculating the radius R1 of the wave limiting hole (11) is: in, is half of the detection angle of the radar chip (31), H0 is the distance from the radar chip (31) to the end of the wave limiting hole (11) away from the radar chip (31), L1 is the maximum antenna edge distance of the antenna component in the x direction; x is the horizontal coordinate axis of the plane where the radar chip (31) has the surface of the antenna component.
9. The millimeter wave radar monitoring range constraint device according to claim 7, characterized in that: The cross section of the wave limiting hole (11) is circular, the center of the wave limiting hole (11) and the center of the radar chip (31) are located on the same axis, and the formula for calculating the radius R2 of the wave limiting hole (11) is: in, is half of the detection angle of the radar chip (31), H0 is the distance from the radar chip (31) to the end of the wave limiting hole (11) away from the radar chip (31), L2 is the maximum antenna edge distance of the antenna component in the y direction; y is the vertical coordinate axis of the plane where the radar chip (31) has the surface of the antenna component.
10. The millimeter wave radar monitoring range constraint device according to claim 7, characterized in that: The millimeter wave radar antenna structure (3) also includes a circuit board (32), the radar chip (31) is mounted on the circuit board (32), and the circuit board (32) is used to conduct circuits and position the radar chip (31).