Wave absorbing structure, antenna, radar and terminal

Abstract

The invention discloses a wave absorbing structure, an antenna, a radar and a terminal. The wave absorbing structure comprises a resonance part, a load and a wave absorbing part. The resonating portion may be configured to resonate with an antenna unit in the antenna for radiating a signal. When the resonance part resonates with the antenna unit, the resonance part can couple and receive energy from the antenna unit. The resonating portion may feed power to the load to transfer the energy to the load. The wave absorbing part covers the load, so that the energy of the load can be absorbed. Therefore, the energy of the antenna unit coupled to the wave absorbing structure is absorbed, so that the surface wave of the antenna unit can be reduced, the consistency of an antenna pattern is improved, and the detection precision of the radar can be improved.

Description

Wave absorbing structure, antenna, radar and terminal Technical Field

[0001] The present application relates to the field of communication technology, and in particular to an absorbing structure, an antenna, a radar and a terminal. Background Art

[0002] With the development of automotive radar, the requirements for antenna performance are becoming increasingly stringent. Among them, pattern consistency is one of the most important antenna characteristics. The better the antenna pattern consistency, the higher the radar detection accuracy.

[0003] Array antennas are commonly used in automotive radars. However, coupling paths such as surface waves, spatial energy, and feeder stray radiation can cause pattern jitter, leading to poor pattern consistency and thus affecting antenna performance. Therefore, improving antenna pattern consistency is an urgent issue to be addressed.

[0004] Summary of the Invention

[0005] The present application provides an absorbing structure, an antenna, a radar and a terminal to improve the consistency of the antenna pattern, thereby improving the detection accuracy of the radar.

[0006] In a first aspect, the present application provides an absorbing structure. The absorbing structure includes a resonating portion, a load, and an absorbing portion. Specifically, the resonating portion is configured to resonate with an antenna unit for radiating a signal and to feed power to the load. The absorbing portion is configured to cover the load and absorb energy from the load.

[0007] When used in an antenna, the resonant portion resonates with the antenna element, coupling energy from the antenna element. The resonant portion then feeds the load, transferring the coupled energy to the load. This energy is then absorbed by the absorbing portion, reducing surface waves in the antenna element and improving the consistency of the antenna pattern.

[0008] Specifically, the resonant part can be used to resonate at the same frequency as the antenna unit, which is characterized by the same frequency band. In this way, the resonant part can have the same or similar working mode as the antenna unit and can effectively transfer the energy of the antenna unit to the load.

[0009] When the resonant part does not match the load, the wave absorbing structure may further include an impedance transformation part, so that the resonant part is connected to the load through the impedance transformation part, thereby enabling the resonant part to feed power to the load.

[0010] The present application does not impose any specific restrictions on the type of the impedance transformation portion. For example, it may be a single-stage impedance transformation portion, a multi-stage impedance transformation portion, or a gradient impedance transformation portion.

[0011] In the technical solution of the present application, there is no specific restriction on the type of load. For example, the load can be a single-resonant load or a multi-resonant load. The shape of the load can be fan-shaped, trapezoidal, rectangular, or spiral, etc., which is not specifically limited here.

[0012] When the absorbing portion is provided, the absorbing portion can be connected to the dielectric substrate where the antenna unit is located to fix the position of the absorbing portion. Specifically, the absorbing portion can be connected to the dielectric substrate by means of heat riveting, gluing or threaded connection.

[0013] In a second aspect, the present application provides an antenna. The antenna specifically includes at least one antenna unit, a dielectric substrate, and the absorbing structure of the first aspect. In this antenna structure, the absorbing structure can resonantly couple with the antenna unit and absorb the coupled energy, thereby reducing the surface waves of the antenna unit and improving the consistency of the antenna pattern.

[0014] In a specific application, the antenna may further include a chip, which is disposed on a dielectric substrate and connected to the antenna unit, so as to control the antenna unit through the chip.

[0015] In a specific technical solution, the absorbing portion of the absorbing structure can cover the chip. In this way, the absorbing portion can simultaneously absorb energy from the load and the chip, thereby simplifying the antenna manufacturing process and manufacturing costs.

[0016] In another specific technical solution, the antenna may also include an absorbing layer that covers the chip. In this technical solution, the absorbing portion is used to absorb energy from the load, while the absorbing layer is used to absorb energy from the chip layer. Of course, the absorbing portion and the absorbing layer can be made of the same material, thereby reducing the manufacturing cost of the antenna.

[0017] In this application, the specific layout of the antenna units and absorbing structures is not limited. The number and layout of the absorbing structures can be designed based on the layout of the antenna units. For example, in some technical solutions, the at least one antenna unit may include a first antenna unit and a second antenna unit, and the absorbing structure may include a first absorbing structure. The first absorbing structure is disposed between the first antenna unit and the second antenna unit, so that the first absorbing structure can absorb energy from the adjacent first and second antenna units. In other words, when the antenna includes at least two antenna units, the absorbing structure can be disposed between two adjacent antenna units.

[0018] In some other technical solutions, the at least one antenna unit may include a third antenna unit and a fourth antenna unit disposed adjacent to each other, and the absorbing structure may include a second absorbing structure. The second absorbing structure is disposed on one side of the third antenna unit. In other words, when the antenna includes at least two adjacent antenna units, the absorbing structure may also be disposed on one side of these antenna units.

[0019] In practical applications, the antenna can adopt various antenna array layouts. For example, in a specific technical solution, the at least one antenna unit may include M fifth antenna units and N sixth antenna units, where M ≥ 2 and N ≥ 1. The absorbing structure may include a third absorbing structure and a fourth absorbing structure. The M fifth antenna units have gaps between them, and the third absorbing structure may be provided between two adjacent fifth antenna units. The N sixth antenna units are arranged adjacent to each other, and the fourth absorbing structure may be provided on at least one side of the N sixth antenna units.

[0020] In the present application, there is no specific limitation on the type of antenna unit. For example, the antenna unit may be a microstrip antenna, a waveguide antenna, a slot antenna, or the like.

[0021] In a third aspect, the present application provides a radar. The radar includes a housing and at least one antenna according to the second aspect, wherein the at least one antenna is disposed within the housing. In the radar, the antenna's absorbing structure can resonate with the antenna unit and couple energy, absorbing the coupled energy, thereby reducing the surface wave of the antenna unit, improving the consistency of the antenna pattern, and thereby improving the radar's detection accuracy. It is understood that in specific applications, the specific shape and material of the housing can be reasonably set according to actual conditions, and this application does not impose any limitations on this.

[0022] In a fourth aspect, the present application provides a terminal. The terminal includes a controller and the radar of the third aspect. The controller is connected to the radar to effectively control the operating status of the radar; alternatively, the controller can also process data received from the radar for use in driving decisions. The terminal can be a vehicle, a mobile phone, a base station, a ship, a satellite, an aircraft, or a drone, etc. The present application does not limit the specific application scenario of the radar. The terminal uses the radar of the third aspect to achieve relatively accurate detection, thereby enabling real-time detection of the environment surrounding the terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic structural diagram of an absorbing structure in an embodiment of the present application;

[0024] FIG2 is a schematic cross-sectional view of the wave absorbing structure in FIG1 along the AA direction;

[0025] FIG3 is another schematic structural diagram of the wave absorbing structure in an embodiment of the present application;

[0026] FIG4 is another schematic structural diagram of the wave absorbing structure in an embodiment of the present application;

[0027] FIG5 is another schematic structural diagram of the wave absorbing structure in an embodiment of the present application;

[0028] FIG6 is another schematic structural diagram of the wave absorbing structure in an embodiment of the present application;

[0029] FIG7 is another schematic structural diagram of the wave absorbing structure in an embodiment of the present application;

[0030] FIG8 is a schematic diagram of the return loss of the absorbing structure in FIG1 ;

[0031] FIG9 is a schematic structural diagram of an antenna according to an embodiment of the present application;

[0032] FIG10 is a schematic cross-sectional view of the antenna in FIG9 along the BB direction;

[0033] FIG11 is another schematic structural diagram of an antenna in an embodiment of the present application;

[0034] FIG12 is another schematic diagram of the structure of the antenna in the embodiment of the present application;

[0035] FIG13 is a schematic cross-sectional view of the antenna in FIG12 along the CC direction;

[0036] FIG14 is another schematic diagram of the structure of the antenna in an embodiment of the present application;

[0037] FIG15 is another schematic diagram of the structure of the antenna in an embodiment of the present application;

[0038] FIG16 is another schematic diagram of the structure of the antenna in an embodiment of the present application;

[0039] FIG17 is a horizontal radiation pattern of an antenna without an absorbing structure at a frequency of 76 GHz;

[0040] FIG18 is a horizontal radiation pattern of an antenna with an absorbing structure at a frequency of 76 GHz;

[0041] FIG19 is a horizontal radiation pattern of an antenna without an absorbing structure at a frequency of 81 GHz;

[0042] FIG20 is a horizontal radiation pattern of an antenna with an absorbing structure at a frequency of 81 GHz.

[0043] Reference numerals:

[0044] 10-wave absorbing structure; 11-resonance part;

[0045] 12- load; 13- absorber;

[0046] 14- impedance transformation unit; 20- antenna;

[0047] 21-antenna unit; 22-dielectric substrate;

[0048] 23-chip; 24-absorbing layer;

[0049] 25-ground plate; 10a-first absorbing structure;

[0050] 10b-second absorbing structure; 10c-third absorbing structure;

[0051] 10d-fourth absorbing structure; 21a-first antenna unit;

[0052] 21b- second antenna unit; 21c- third antenna unit;

[0053] 21d-fourth antenna unit; 21e-fifth antenna unit;

[0054] 21f-sixth antenna element. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of this application clearer, this application will be further described in detail below with reference to the accompanying drawings.

[0056] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in another embodiment," "in some other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0057] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of this application, the singular expressions "a", "an", "said", "above", "the", and "this" are intended to also include expressions such as "one or more", unless the context clearly indicates otherwise.

[0058] With the development of communication technology, radar has become widely used in vehicles. Radar typically uses a planar antenna to transmit and receive electromagnetic waves to obtain the position information of the object being measured. Taking automotive millimeter-wave radar as an example, automotive millimeter-wave radar can transmit and receive millimeter waves using a microstrip antenna, and then quickly and accurately obtain information about the object being measured after processing. However, during the transmission and reception of millimeter waves, the microstrip antenna excites surface waves on the surface of the dielectric substrate. Surface waves radiate at discontinuities, affecting the antenna bandwidth and distorting the radiation pattern generated by the microstrip antenna, thus affecting the detection accuracy of the automotive millimeter-wave radar.

[0059] Therefore, the present application provides an absorbing structure, an antenna, a radar and a terminal to improve the consistency of the antenna pattern, thereby improving the detection accuracy of the radar.

[0060] Figure 1 is a schematic diagram of a wave-absorbing structure according to an embodiment of the present application, and Figure 2 is a schematic cross-sectional view of the wave-absorbing structure in Figure 1 along the AA direction. As shown in Figures 1 and 2, the present application provides a wave-absorbing structure 10. This wave-absorbing structure 10 can be applied to antennas or other devices that require absorption of radiated energy. The following description of the wave-absorbing structure 10 will use antenna applications as an example.

[0061] When the absorbing structure 10 is used in an antenna, it can be placed on the dielectric substrate 22 of the antenna. Specifically, the absorbing structure 10 includes a resonating portion 11, a load 12, and an absorbing portion 13. The resonating portion 11 can be configured to resonate with the antenna element of the antenna, which radiates signals. When the resonating portion 11 resonates with the antenna element, energy can be coupled from the antenna element to the resonating portion 11. The resonating portion 11 can feed power to the load 12, thereby transferring energy coupled from the antenna element to the load 12. For ease of illustration, the position of the absorbing portion 13 is indicated only by dashed lines in Figure 1, and the shape and size of the absorbing portion 13 are not limited. In practice, as shown in Figure 2, when the load 12 is placed on the dielectric substrate 22, the absorbing portion 13 covers the load 12 to absorb energy from the load 12. In other words, the absorbing portion 13 surrounds the load 12, allowing the energy radiated by the load 12 to be absorbed by the absorbing portion 13. In addition, to more effectively absorb the energy from the load 12, the absorbing portion 13 can be fixed so that it covers the load 12. For example, in one specific embodiment, the absorbing portion 13 can be connected to the dielectric substrate 22 to secure the position of the absorbing portion 13. In this embodiment, the connection between the absorbing portion 13 and the dielectric substrate 22 can be achieved by heat staking, gluing, or threading, without limitation. Of course, in other embodiments, the absorbing portion 13 can also be connected to the load 12. In this way, energy coupled from the antenna unit to the absorbing structure 10 is absorbed by the absorbing portion 13, thereby reducing the surface waves of the antenna unit and improving the consistency of the antenna pattern.

[0062] The resonant portion 11 resonates with the antenna unit to transfer the antenna unit's energy to the absorbing structure 10. For example, in some embodiments, the resonance may be co-frequency resonance, meaning that the resonant portion 11 can be configured to resonate with the antenna unit at the same frequency, where the co-frequency is defined as being in the same frequency band. Thus, when the antenna is operating, the resonant portion 11 resonates within the antenna unit's operating frequency band. This allows the resonant portion 11 to have the same or similar operating mode as the antenna unit, thereby effectively transferring the antenna unit's energy to the load 12.

[0063] In some embodiments, when the resonant portion 11 matches the load 12, the resonant portion 11 can be directly connected to the load 12 to feed power to the load 12. When the resonant portion 11 does not match the load 12, the absorbing structure 10 can optionally further include an impedance transformation portion 14, thereby connecting the resonant portion 11 to the load 12 via the impedance transformation portion 14, thereby performing impedance transformation on the energy coupled by the resonant portion 11 from the antenna unit before feeding power to the load 12.

[0064] It should be noted that the embodiments of the present application do not limit the specific type of the above-mentioned impedance transformation portion 14, and the function of achieving impedance transformation shall prevail. As shown in Figure 1, in some embodiments, the impedance transformation portion 14 may be a multi-stage impedance transformation portion. Figure 3 is a schematic diagram of another structure of the absorbing structure in the embodiments of the present application. As shown in Figure 3, in some other embodiments, the impedance transformation portion 14 may also be a single-stage impedance transformation portion. Figure 4 is a schematic diagram of another structure of the absorbing structure in the embodiments of the present application. As shown in Figure 4, in some other embodiments, the impedance transformation portion 14 may also be a gradient impedance transformation portion.

[0065] In the embodiments of the present application, there are no specific restrictions on the type of load 12. For example, the load 12 can be a single-resonant load or a multi-resonant load. Furthermore, there are no restrictions on the specific shape of the load 12. As shown in Figures 1 to 4, in some embodiments, the load 12 can be fan-shaped. Figure 5 is a schematic diagram of another structure of the absorbing structure in the embodiments of the present application. As shown in Figure 5, in other embodiments, the load 12 can also be trapezoidal. Figure 6 is a schematic diagram of another structure of the absorbing structure in the embodiments of the present application. As shown in Figure 6, in other embodiments, the load 12 can also be rectangular. Furthermore, the load 12 can also be a spiral or irregular shape, etc., without specific restrictions here. Of course, in actual applications, the coupled energy can be determined based on the operating mode of the antenna unit, thereby designing the specific type, shape, and / or dimensions of the load 12. Figure 7 is a schematic diagram of another structure of the absorbing structure in the embodiments of the present application. As shown in Figure 7, in one specific embodiment, the load 12 can also be an irregular shape that combines a trapezoidal and fan-shaped shape. In another specific embodiment, the load 12 can also be an irregular shape that combines a trapezoidal and rectangular structure.

[0066] It should be noted that, in order to illustrate the load 12 and the impedance transformation part 14 , the absorbing part 13 is omitted from the absorbing structure 10 in FIG. 3 to FIG. 7 .

[0067] When the absorbing structure 10 is working, the return loss (RL) of the absorbing structure 10 changes with the change of frequency. In the field of communications, return loss refers to the ratio of the power reflected back from the input signal to the power of the input signal. Usually, return loss is measured in decibels (dB) and the value is a negative number. Ideally, when the absorbing structure 10 of the present application is completely matched with the impedance, the reflected power is zero, that is, there is no reflected power at all, and the return loss is infinitesimal at this time. When the input power is completely reflected, the return loss is 0dB. However, in actual applications, it is impossible for the impedance to be completely matched. Therefore, there is reflected power in the absorbing structure 10, and the smaller the value of the return loss, the better the absorbing performance of the absorbing structure 10.

[0068] FIG8 is a schematic diagram of the return loss of the absorbing structure in FIG1 . As shown in FIG8 , the operating frequency of the antenna unit is between 73 GHz and 81 GHz as an example. Generally speaking, in the field of mobile communications, the return loss is generally required to be less than -14 dB, while the return loss of the absorbing structure 10 of the present application is between -45 dB and -47 dB. In other words, the absorbing structure 10 does not generate a large amount of return loss when absorbing the energy of the antenna unit, and can suppress the radiation of the surface wave on the antenna array, thereby improving the energy coupling between the antenna units and improving the consistency of the antenna pattern.

[0069] Based on the same technical concept, the present application provides an antenna. Figure 9 is a structural schematic diagram of the antenna in an embodiment of the present application, and Figure 10 is a cross-sectional schematic diagram of the antenna in Figure 9 along the BB direction. As shown in Figures 9 and 10, the antenna 20 specifically includes at least one antenna unit 21, a dielectric substrate 22, and the absorbing structure 10 of the above embodiment. In the antenna 20 of this structure, the antenna unit 21 and the absorbing structure 10 can be arranged on the same side of the dielectric substrate 22 and arranged adjacent to each other. The absorbing structure 10 is used to resonantly couple with the antenna unit 21 and absorb the coupled energy, thereby reducing the surface wave of the antenna unit 21 and improving the consistency of the directional pattern of the antenna 20.

[0070] Figure 11 is a schematic diagram of another antenna structure in an embodiment of the present application. As shown in Figure 11, in one specific embodiment, antenna unit 21 is a waveguide antenna. Resonating portion 11 of absorbing structure 10 is connected to antenna unit 21 and resonates therewith. Of course, antenna unit 21 can also be a microstrip antenna or a slot antenna, etc., without specific limitation herein.

[0071] Continuing with Figures 9 and 10 , the antenna 20 may further include a chip 23. This chip 23 is disposed on the dielectric substrate 22 and connected to the antenna unit 21, enabling control of the antenna unit 21 via the chip 23. In some embodiments of the present application, the absorbing portion 13 may cover the chip 23. In such embodiments, the absorbing portion 13 can simultaneously absorb energy from both the load 12 and the chip 23, thereby simplifying the manufacturing process and cost of the antenna 20. Furthermore, in specific applications, the antenna 20 may further include a ground plane 25. The ground plane 25 is disposed on the side of the dielectric substrate 22 facing away from the antenna unit 21.

[0072] Figure 12 is a schematic diagram of another structure of an antenna according to an embodiment of the present application, and Figure 13 is a schematic cross-sectional view of the antenna in Figure 12 along the CC direction. As shown in Figures 12 and 13, in some other embodiments, antenna 20 may also include an absorbing layer 24, which covers chip 23. In this embodiment, absorbing portion 13 is used to absorb energy from load 12, while absorbing layer 24 is used to absorb energy from chip 23. Of course, absorbing portion 13 and absorbing layer 24 can be made of the same material, thereby reducing the manufacturing cost of antenna 20.

[0073] In the present application, the specific layout of the antenna unit 21 and the absorbing structure 10 is not limited. Figure 14 is another structural schematic diagram of the antenna in an embodiment of the present application. As shown in Figure 14, in some embodiments, the at least one antenna unit 21 may include a first antenna unit 21a and a second antenna unit 21b, and the absorbing structure 10 may include a first absorbing structure 10a. The first absorbing structure 10a is arranged between the first antenna unit 21a and the second antenna unit 21b, so that the first absorbing structure 10a can absorb the energy of the adjacent first antenna unit 21a and the second antenna unit 21b. That is, when the antenna 20 includes at least two antenna units 21 arranged at intervals, the absorbing structure 10 can be arranged between two adjacent antenna units 21.

[0074] Figure 15 is another schematic diagram of the structure of the antenna in an embodiment of the present application. As shown in Figure 15, in some other embodiments, the at least one antenna unit 21 may include a third antenna unit 21c and a fourth antenna unit 21d that are adjacently distributed, and the absorbing structure 10 includes a second absorbing structure 10b. The second absorbing structure 10b is arranged on one side of the third antenna unit 21c. That is, when the antenna 20 includes at least two adjacently arranged antenna units 21, the absorbing structure 10 can be arranged on one side of these antenna units 21. Of course, the second absorbing structure 10b can also be arranged on the other side of these multiple adjacently arranged antenna units 21, or the second absorbing structure 10b can also be arranged, and there is no specific limitation here.

[0075] In practical applications, the antenna 20 can adopt various antenna array layouts, and the number and position of the absorbing structure 10 can be set according to the specific antenna array layout. Figure 16 is another structural schematic diagram of the antenna in an embodiment of the present application. As shown in Figure 16, in a specific embodiment, the at least one antenna unit 21 may include M fifth antenna units 21e and N sixth antenna units 21f, where M ≥ 2 and N ≥ 1. The absorbing structure 10 may include a third absorbing structure 10c and a fourth absorbing structure 10d. The M fifth antenna units 21e may have gaps between each other, and at least one third absorbing structure 10c is arranged between two adjacent fifth antenna units 21e. The N sixth antenna units 21f are distributed adjacent to each other, and at least one fourth absorbing structure 10d is arranged on at least one side of the N sixth antenna units 21f.

[0076] The antenna 20 is further described by taking the antenna unit 21 as an example of a 3T4R (3 Transmitter & 4 Receiver) antenna unit array. The absorbing structure 10 can resonate with each antenna unit 21. Specifically, the 3T4R antenna unit array includes three fifth antenna units 21e and four sixth antenna units 21f. Two third absorbing structures 10c can be provided between any two adjacent fifth antenna units 21e. In addition, eight absorbing structures 10 can be provided on both sides of the three fifth antenna units 21e. The above-mentioned four sixth antenna units 21f are arranged adjacent to each other, and ten fourth absorbing structures 10d are provided on both sides of the four sixth antenna units 21f.

[0077] Taking the operating frequency of 76 GHz as an example, a 3T4R antenna with an absorbing structure 10 and a 3T4R antenna without an absorbing structure 10 are compared. FIG17 is a horizontal radiation pattern of an antenna without an absorbing structure at a frequency of 76 GHz. It should be noted that the horizontal axis in FIG17 represents the theta (θ, in degrees (deg)) component, and the vertical axis represents the gain (in decibels (dB)). Among them, the schematic diagram above the horizontal axis shows that under the condition of a frequency of 76 GHz, when phi ( The unit is degrees (deg)). When the phi component is 0 degrees, the increments of the four sixth antenna units vary with the change of θ. The schematic diagram below the horizontal axis shows that under the condition of 76 GHz frequency, when the phi component is 90 degrees, the increments of the four sixth antenna units vary with the change of θ. As shown in Figure 17, when the antenna without the absorbing structure 10 operates at a frequency of 76 GHz, due to the influence of surface waves, coupling occurs between the sixth antenna units, causing the gain of the sixth antenna unit to fluctuate greatly at large angles (near theta = ± 70 degrees, as shown in D in Figure 17) in the horizontal plane (i.e., phi = 0 degrees), and the maximum difference in gain is 4.1 dB. Therefore, the consistency between the sixth antenna units is poor. Figure 18 is the horizontal radiation pattern of the antenna with the absorbing structure at a frequency of 76 GHz. It should be noted that the horizontal axis in Figure 18 represents the theta component and the vertical axis represents the gain. Among them, the schematic diagram above the horizontal axis shows that under the condition of 76 GHz frequency, when the phi component is 0 degrees, the increments of the four sixth antenna units 21f vary with the change of θ. The schematic diagram below the abscissa shows how the increments of each of the four sixth antenna elements 21f vary with θ at a frequency of 76 GHz, when the phi component is 90 degrees. As shown in FIG18 , when the antenna 20 of the present embodiment operates at a frequency of 76 GHz, due to the absorption structure 10 absorbing energy from adjacent antenna elements 21, the gain of the sixth antenna element 21f fluctuates significantly at large angles (near theta = ±70 degrees, as shown in FIG18 E) in the horizontal plane (i.e., phi = 0 degrees), and the maximum gain difference is 0.2 dB, which reduces gain fluctuations compared to an antenna without the absorbing structure 10.

[0078] Taking the operating frequency of 81 GHz as an example, a 3T4R antenna with an absorbing structure 10 and a 3T4R antenna without an absorbing structure 10 are compared. Figure 19 is the horizontal radiation pattern of the antenna without an absorbing structure at a frequency of 81 GHz. It should be noted that the horizontal axis in Figure 19 represents the theta component and the vertical axis represents the gain. Among them, the schematic diagram above the horizontal axis shows that under the condition of a frequency of 81 GHz, when the phi component is 0 degrees, the increments of the four sixth antenna units change with the change of θ. The schematic diagram below the horizontal axis shows that under the condition of a frequency of 81 GHz, when the phi component is 90 degrees, the increments of the four sixth antenna units change with the change of θ. As shown in FIG19 , when the antenna without the absorbing structure 10 operates at a frequency of 81 GHz, the influence of surface waves causes coupling between the sixth antenna elements, causing the gain of the sixth antenna element to fluctuate greatly at large angles (near theta = ±70 degrees, as shown by F in FIG19 ) in the horizontal plane (i.e., phi = 0 degrees), and the maximum difference in gain is 7.2 dB. Therefore, the consistency between the sixth antenna elements is poor. FIG20 is the horizontal radiation pattern of the antenna with the absorbing structure at a frequency of 81 GHz. It should be noted that the abscissa in FIG20 represents the theta component and the ordinate represents the gain. The schematic diagram above the abscissa shows that under the condition of a frequency of 81 GHz, when the phi component is 0 degrees, the increments of the four sixth antenna elements 21 f change with the change of θ. The schematic diagram below the abscissa shows that under the condition of a frequency of 81 GHz, when the phi component is 90 degrees, the increments of the four sixth antenna elements 21 f change with the change of θ. As shown in Figure 20, when the antenna 20 of the embodiment of the present application operates at a frequency of 81 GHz, since the absorbing structure 10 absorbs the energy of the adjacent antenna unit 21, the gain of the sixth antenna unit 21f fluctuates greatly at large angles (near theta = ±70 degrees, as shown by G in Figure 20) in the horizontal plane (i.e., phi = 0 degrees), and the maximum difference in gain is 3.8 dB, which reduces the gain fluctuation compared to the antenna without the absorbing structure 10.

[0079] Therefore, the absorbing structure 10 of the present application can effectively absorb the energy of the antenna unit 21, weaken the energy coupling between the antenna units 21, and suppress the surface waves of the antenna, thereby improving the gain fluctuation of the horizontal plane radiation pattern of the antenna 20 at large angles and improving the consistency between the antenna units 21.

[0080] Based on the same technical concept, the present application also provides a radar. Specifically, the radar includes a shell and at least one antenna 20 of the above embodiment. Specifically, the antenna 20 can be arranged in the shell. In the radar of this embodiment, the absorbing structure 10 in the antenna 20 can resonantly couple with the antenna unit 21 in the antenna 20 and absorb the coupled received energy, thereby improving the energy coupling between the antenna units 21, reducing the surface wave of the antenna 20 array, and improving the consistency of the antenna 20 radiation pattern, thereby improving the detection accuracy of the radar. It can be understood that in specific applications, the specific shape and material of the shell can be reasonably set according to actual conditions, and this application does not limit this.

[0081] Based on the same technical concept, this application also provides a terminal. The terminal includes a controller and the radar of the above-described embodiment. The controller is connected to the radar to effectively control its operating status; alternatively, the controller can process data received from the radar for use in driving decisions. The terminal can be a vehicle, mobile phone, base station, ship, satellite, aircraft, or drone, etc. This application does not limit the specific application scenario of the radar.

[0082] Obviously, those skilled in the art may make various modifications and variations to this application without departing from the scope of protection of this application. Thus, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application is intended to include such modifications and variations.

Claims

1. A wave absorbing structure, characterized in that: It includes a resonant part, a load and an absorbing part, wherein: The resonant portion is configured to resonate with an antenna unit for radiating a signal and to feed power to the load; The wave absorbing portion is used to cover the load and absorb the energy of the load.

2. The wave absorbing structure according to claim 1, wherein: The resonant part is used to resonate at the same frequency as the antenna unit, where the same frequency represents the same frequency band.

3. The wave absorbing structure according to claim 1 or 2, characterized in that: The wave absorbing structure further includes an impedance transformation portion, and the impedance transformation portion connects the resonant portion and the load.

4. The wave absorbing structure according to claim 3, wherein: The impedance transformation portion includes a single-stage impedance transformation portion, a multi-stage impedance transformation portion, or a gradient impedance transformation portion.

5. The wave absorbing structure according to any one of claims 1 to 4, characterized in that: The load includes a single-resonance load or a multi-resonance load.

6. The wave absorbing structure according to any one of claims 1 to 5, characterized in that: The load is in the shape of a sector, a trapezoid, a rectangle or a spiral.

7. The wave absorbing structure according to any one of claims 1 to 6, characterized in that: The wave absorbing portion is connected to the dielectric substrate where the antenna unit is located.

8. An antenna, characterized in that: The invention comprises at least one antenna unit, a dielectric substrate and the wave absorbing structure according to any one of claims 1 to 7.

9. The antenna according to claim 8, wherein The antenna further includes a chip, which is disposed on the dielectric substrate and connected to the at least one antenna unit.

10. The antenna according to claim 9, wherein The wave absorbing portion covers the chip.

11. The antenna according to claim 9, wherein The antenna further includes a wave absorbing layer, and the wave absorbing layer covers the chip.

12. The antenna according to any one of claims 8 to 11, characterized in that The at least one antenna unit includes a first antenna unit and a second antenna unit, and the absorbing structure includes a first absorbing structure, which is arranged between the first antenna unit and the second antenna unit.

13. The antenna according to any one of claims 8 to 11, characterized in that The at least one antenna unit includes a third antenna unit and a fourth antenna unit that are adjacently distributed, and the absorbing structure includes a second absorbing structure that is arranged on one side of the third antenna unit.

14. The antenna according to any one of claims 8 to 11, characterized in that The at least one antenna unit includes M fifth antenna units and N sixth antenna units, where M ≥ 2 and N ≥ 1; the absorbing structure includes a third absorbing structure and a fourth absorbing structure, the M fifth antenna units have gaps between each other, the third absorbing structure is arranged between two adjacent fifth antenna units, the N sixth antenna units are distributed adjacent to each other, and the fourth absorbing structure is arranged on at least one side of the N sixth antenna units.

15. The antenna according to any one of claims 8 to 14, characterized in that The antenna unit includes a microstrip antenna, a waveguide antenna or a slot antenna.

16. A radar, characterized in that: The device comprises a housing, and at least one antenna according to any one of claims 8 to 15, wherein the at least one antenna is arranged in the housing.

17. A terminal, characterized in that: The invention comprises a controller and the radar according to claim 16, wherein the controller is connected to the radar.

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