Antenna structure, radar sensor and electronic equipment

Abstract

The embodiment of the invention provides an antenna structure, a radar sensor and electronic equipment. The antenna structure comprises a waveguide feed structure and a radiation structure arranged on a first surface of the waveguide feed structure, the radiation structure comprises at least two radiation units, and the radiation units are dipole units; the waveguide feed structure comprises a waveguide channel, gaps communicated with the waveguide channel are formed in the positions, corresponding to the radiation units, of the first surface, and the portion, between every two adjacent gaps, of the waveguide channel is provided with a bending structure. And the length of the waveguide channel between the two adjacent gaps enables the directions of currents on the two adjacent radiation units adjacent to the two gaps to be consistent. Compared with an existing waveguide slot antenna scheme, the antenna provided by the embodiment of the invention is smaller in structure size and high in directional diagram stability.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to, but are not limited to, the field of antenna packaging technology, and in particular, to an antenna structure, a radar sensor, and an electronic device. Background Art

[0002] In recent years, automobiles have been developing towards intelligence and electrification. With the upgrade and evolution of the L2-level autonomous driving functions of automobiles, such as the realization of functions like lane change assistance, automatic cruise, automatic parking, and emergency automatic braking, the vehicle installation rate of millimeter-wave corner radars has also increased rapidly. To meet the application requirements such as blind spot detection and collision avoidance warning, millimeter-wave radars need to have the characteristic of a wide field of view (FOV). To meet the wide FOV requirement of millimeter-wave corner radars, a wide-beam antenna needs to be used in the radar radio frequency front end. To achieve good transceiver performance, miniaturization design of the antenna is required. Summary of the Invention

[0003] Embodiments of the present disclosure provide an antenna structure, a radar sensor, and an electronic device, which are small in size, high in stability, and wide in beam surface.

[0004] On the one hand, embodiments of the present disclosure provide an antenna structure, including a waveguide feeding structure and a radiation structure arranged on a first surface of the waveguide feeding structure, wherein:

[0005] The radiation structure includes at least two radiation units, and the radiation unit is a dipole unit;

[0006] The waveguide feeding structure includes a waveguide channel, and gaps communicating with the waveguide channel are respectively arranged at positions corresponding to the radiation units on the first surface. The waveguide channel between two adjacent gaps has a bent structure, and the length of the waveguide channel between the two adjacent gaps enables the current directions on two adjacent radiation units adjacent to the two gaps to be the same.

[0007] In an exemplary embodiment, the length of the waveguide channel with a bent structure between two adjacent gaps is an integer multiple of the air wavelength.

[0008] In an exemplary embodiment, the bent structure of the waveguide channel between two adjacent gaps is in a U shape.

[0009] In an exemplary embodiment, the waveguide feeding structure includes a body and a top cover, the body and the top cover form the waveguide channel, the gaps are arranged at positions corresponding to the radiation units on a first surface of the top cover, and one radiation unit is arranged at each gap.

[0010] In an exemplary embodiment, each radiation unit includes two radiation branches, which are disposed on the first surface of the waveguide feeding structure and symmetrically disposed on both sides of the slit with a slit as the axis of symmetry.

[0011] In an exemplary embodiment, the radiation branch is strip-shaped, the extending direction of the strip-shaped radiation branch is the first direction, the extending direction of the slit is the second direction, and the first direction is perpendicular to the second direction.

[0012] In an exemplary embodiment, the center lines of the strip-shaped radiation branches of all radiation units coincide in the extending direction.

[0013] In an exemplary embodiment, the distance between two adjacent radiation units is λ / 2, where λ is the air wavelength.

[0014] In an exemplary embodiment, the center distance between two adjacent slits is less than λ and greater than 0.5λ, where λ is the air wavelength.

[0015] In an exemplary embodiment, the maximum distance between two radiation branches in one radiation unit is λ / 2, where λ is the air wavelength.

[0016] On the other hand, an embodiment of the present disclosure further provides a radar sensor including the foregoing antenna structure.

[0017] On yet another aspect, an embodiment of the present disclosure further provides an electronic device including the foregoing radar sensor.

[0018] The antenna structure of the embodiment of the present disclosure feeds power to the radiation unit using a waveguide structure, ensures the current direction of the radiation unit by setting a bending structure in the waveguide structure, and uses a dipole unit whose polarization plane and the wide beam plane of the radiation pattern are not in the same horizontal direction as the radiation unit, so that the radiation pattern of the antenna is not easily affected by the surrounding environment and jitters. Compared with the existing waveguide slot antenna solution, the antenna structure of the embodiment of the present disclosure has a smaller size and high radiation pattern stability.

[0019] Other features and advantages of the present application will be described in the subsequent specification, and part of them will become obvious from the specification, or will be understood by implementing the present application. Other advantages of the present application can be realized and obtained through the solutions described in the specification and the drawings. Description of the Drawings

[0020] The drawings are used to provide an understanding of the technical solutions of the present application, and constitute a part of the specification. They are used together with the embodiments of the present application to explain the technical solutions of the present application, and do not constitute a limitation to the technical solutions of the present application.

[0021] Figure 1 It is a wide beam slot antenna with surface slots;

[0022] Figure 2 is a schematic diagram of the surface current of a traditional rectangular waveguide;

[0023] Figure 3 is a schematic diagram of an antenna structure according to an embodiment of the present disclosure;

[0024] Figure 4A is a cross-sectional view of the antenna structure of this application example;

[0025] Figure 4B is a top view of the antenna structure of this application example;

[0026] Figure 5 is a top view of another bending method of the waveguide structure according to an embodiment of the present disclosure;

[0027] Figure 6 is Figure 4A the horizontal radiation pattern of the antenna structure shown;

[0028] Figure 7 is a schematic diagram of arranging the folded waveguide dipole antenna structure according to an embodiment of the present disclosure on a large waveguide plate;

[0029] Figure 8 is a comparison diagram of the horizontal radiation patterns when the antenna structure of this embodiment is respectively arranged on waveguide plates of two sizes;

[0030] Figure 9 is a schematic diagram of a radar sensor provided by an embodiment of the present disclosure;

[0031] Figure 10 is another schematic diagram of a radar sensor provided by an embodiment of the present disclosure. Detailed implementation manners

[0032] The present disclosure describes multiple embodiments, but the description is exemplary rather than restrictive, and it will be apparent to those of ordinary skill in the art that there can be more embodiments and implementation schemes within the scope of the embodiments described in the present disclosure. Although many possible feature combinations are shown in the drawings and discussed in the detailed implementation manners, many other combination ways of the disclosed features are also possible. Unless specifically restricted, any feature or element of any embodiment can be combined with any other feature or element in any other embodiment, or can replace any other feature or element in any other embodiment.

[0033] A waveguide antenna is a type of antenna used for wireless communication. It consists of a metal pipe or waveguide and can transmit electromagnetic waves into space. Waveguide antennas can achieve efficient energy conversion and low signal loss. The medium of the waveguide antenna is air, which can achieve high-gain antenna performance. Currently, waveguide antennas usually adopt the form of surface slots to achieve a wide beam pattern, such as Figure 1 shown. For this type of waveguide slot antenna, since its polarization plane and the wide beam plane of the pattern are in the same horizontal plane, the pattern is easily affected by the environment and thus jitters.

[0034] Such as Figure 2 shown, usually to achieve single-mode transmission in the waveguide, the waveguide width a needs to satisfy: 0.5λg < a < λg, that is, an antenna array needs to be arranged with a 0.5λ spacing, where λ is the air wavelength. However, the current wide beam antennas are relatively large in size, and the antennas overlap with each other, so it is impossible to arrange them with a 0.5λ spacing, and good transceiver performance cannot be achieved. Moreover, the pattern is easily affected by the surrounding environment such as the size of the waveguide plate and metal devices, resulting in jitters and affecting the radar detection performance.

[0035] To achieve a small-sized wide beam antenna, an antenna structure is designed in the embodiments of the present disclosure, such as Figure 3 , Figure 4A and Figure 4B shown. The antenna structure includes a waveguide feeding structure 10 and a radiation structure 20 arranged on the first surface of the waveguide feeding structure 10, where:

[0036] The radiation structure 20 includes at least two radiation units 21, and the radiation unit 21 is a dipole unit;

[0037] The feeding structure 10 includes a waveguide channel 13. Slots 121 communicating with the waveguide channel are respectively arranged at positions corresponding to the radiation units 21 on the first surface. The waveguide channel between two adjacent slots 121 has a bending structure 111, and the length of the waveguide channel between the two adjacent slots 121 (the length shown by the dotted line in the figure) makes the current directions on two adjacent radiation units (such as Figure 4A 21-1 and 21-2 in

[0038] The antenna structure of the embodiments of the present disclosure uses a dipole unit whose polarization plane and the wide beam plane of the radiation pattern are not in the same horizontal direction as the radiation unit, so that the radiation pattern of the antenna is not easily affected by the surrounding environment and jitters. After the dipole unit is set, in order to take into account the radiation effect of the dipole unit (such as reducing sidelobes) and the in-phase of the first surface current cut by the slot on the waveguide feeding structure (to ensure that the current directions on the dipole units are the same), a bending structure is set in the waveguide structure so that the length of the waveguide channel between two adjacent slots can meet the above requirements. Compared with the existing waveguide slot antenna solutions, the antenna structure of the embodiments of the present disclosure has high radiation pattern stability, can achieve a wide beam, and has a smaller size.

[0039] In an exemplary embodiment, the waveguide feeding structure may be composed of a body and a top cover. The body and the top cover form a waveguide channel 13. At least two slots 121 for coupling energy are provided on the first surface of the top cover. A radiation unit 21 is correspondingly arranged at each slot 121. The radiation unit 21 is used to receive the energy coupled from the corresponding slot 121 and convert it into an electromagnetic wave signal for transmission. The radiation unit uses a dipole unit, and its polarization plane and the wide beam plane of the radiation pattern are not in the same horizontal direction, so that it can be ensured that the radiation pattern of the antenna structure is not easily affected by the surrounding environment and jitters, and has higher stability.

[0040] The body and the top cover of the waveguide feeding structure in this embodiment may be prepared separately and then spliced into one body, or may be integrally formed, such as by 3D printing or injection molding process, etc.

[0041] The waveguide feeding structure with a bending structure in this embodiment can be obtained from a rectangular waveguide, a cylindrical waveguide or an elliptical waveguide, that is, the cross-section of the waveguide channel can be rectangular, circular or elliptical. Figure 3 Taking the rectangular waveguide as an example in FIG. 4. The waveguide feeding structure of this embodiment can be regarded as formed after bending the waveguide wall of the rectangular waveguide.

[0042] In an exemplary embodiment, the length of the waveguide channel with a bending structure between two adjacent slots 121 is an integer multiple of the wavelength of the spatial medium (such as air). This can ensure that the circuit directions coupled from the slots to the radiation units are the same.

[0043] In an exemplary embodiment, the bending structure of the waveguide channel between two adjacent slots may be in a U shape. For example, the U-shaped bending structure may protrude away from the top cover, or may be bent into a U shape in a plane parallel to the top cover. In other examples, it may also be in an L shape, a V shape or an S shape, etc.

[0044] In an exemplary embodiment, the dipole unit serving as a radiation unit includes two radiation branches, and the two radiation branches are disposed on the first surface of the waveguide feeding structure and symmetrically disposed on both sides of the slot with the slot as the axis of symmetry, so as to receive the energy coupled by the waveguide feeding structure through the slot.

[0045] Exemplarily, the orthographic projection of the radiation branch on the top cover may be strip-shaped, the extending direction is the first direction (Y direction in the figure), the extending direction of the slot is the X direction, and the X direction is perpendicular to the Y direction. Such a setting can enable the energy coupled out by the slot to be better received by the radiation branch, ensuring a good coupling effect. The extending direction of the radiation branch can be considered to be all towards the first direction, or it can also be considered to be towards the opposite direction of the first direction. For example Figure 3 in FIG. 211 can be considered to extend from the edge of the slot in the Y direction, and in FIG. 212 can be considered to extend from the edge of the slot in the opposite direction of the Y direction, as long as the long side direction of the projection of the radiation branch is parallel to the Y direction.

[0046] In an exemplary embodiment, the center lines of the strip-shaped radiation branches of all radiation units coincide in the extending direction. For example, if the extending direction of the strip-shaped radiation branch is the first direction, the radiation branches in each radiation unit are arranged along the first direction and the center lines of the radiation branches in the first direction coincide, then the current directions on all radiation units are the same, all being the first direction or the opposite direction of the first direction.

[0047] In an exemplary embodiment, the center distance between two adjacent slots is less than λ and greater than 0.5λ, where λ is the spatial medium wavelength, which is the air wavelength in this example, so as to ensure that the surface currents on the radiation branches in the radiation unit are in the same direction.

[0048] In an exemplary embodiment, the distance between two adjacent radiation units is λ / 2, where λ is the air wavelength, which can reduce the side lobe of the antenna in the Y direction and ensure the radiation effect.

[0049] In an exemplary embodiment, the maximum distance between the two radiation branches in a radiation unit, that is, the length of a radiation unit, is λ / 2, where λ is the air wavelength.

[0050] In the embodiment of the present disclosure, by using a dipole as the antenna unit, since the polarization plane of the dipole antenna and the wide beam plane of its radiation pattern are not in the same horizontal direction, the radiation pattern thereof is not easily affected by the surrounding environment and jitters. Compared with the wide beam scheme described above, the radiation pattern of the antenna structure in the embodiment of the present disclosure has strong stability and is not easily affected by the surrounding environment. In addition, since the feeding unit in this embodiment has a waveguide structure with a bent structure, and the length of the bent structure can make the current directions on two adjacent radiation units consistent, the miniaturized design of the antenna can be realized, meeting the requirements of antenna array layout with a small pitch.

[0051] In this embodiment, the bending form of the waveguide is only an example. As long as the surface current of the waveguide cut by the slot is consistent after the waveguide structure is bent, a dipole antenna with a wide beam can be realized.

[0052] Taking the feeding of three feeding units to four radiation units as an example, the antenna structure of the embodiments of the present disclosure will be described. In this example, the radiation unit is implemented by a dipole antenna unit. And by arranging a plurality of dipole antenna units to form a dipole array, a wide-beam antenna is realized. The feeding unit is a waveguide structure, which can reduce the width of the antenna structure.

[0053] Figure 4A is a cross-sectional view of the antenna structure of this example, Figure 4B is a top view of the antenna structure of this example. As shown in the figure, the antenna structure includes a waveguide feeding structure 10 and a radiation structure 20. In this example, the waveguide feeding structure 10 includes 3 feeding units 14, and the radiation structure 20 includes 4 radiation units 21. Among them, the waveguide feeding structure 10 is a waveguide structure with a bending structure 111. As Figure 4A shown, it includes a body 11 and a top cover 12. A waveguide channel 13 is formed between the body 11 and the top cover 12 for receiving an electrical signal and radiating the electromagnetic wave in the waveguide outward. A slot 121 is provided on the first surface of the top cover 12. The slot 121 is used to cut the surface current of the waveguide structure and couple the energy to the metal block (i.e., the aforementioned radiation stub) of the dipole antenna unit. In this example, the extending direction of the slot 121 is the X direction, which is perpendicular to the extending direction Y of the antenna structure. The extending direction of the slot is parallel to the wide side of the antenna structure in the X direction, and the current in the Y direction can be cut. The metal blocks located on both sides of the slot can receive the energy coupled out from the slot 121 and form a dipole antenna to radiate into space. In this example, the shape of the slot 121 is rectangular. In other examples, the slot can be other shapes such as square, parallelogram, trapezoid, circle, etc., as long as it can perform coupling feeding. The present disclosure does not limit this.

[0054] According to Figure 2 the waveguide surface current distribution, when the slots are placed every half wavelength, the current in the Y direction cut is reversed. Therefore, in order to reduce the sidelobe in the Y direction of the antenna array, the dipole antenna units are preferably placed at intervals of half a wavelength, that is, L1 = 0.5λ in Figure A, where λ is the air wavelength.

[0055] In order to make the surface currents of the dipole units in the same direction, the range of the center distance d1 between adjacent dipole units, that is, the center distance between adjacent slots, satisfies: 0.5λ < d1 < λ. The waveguide structure is set to have a bending structure. In this example, the waveguide structure bulges away from the radiation unit to achieve bending. In other examples, the waveguide structure can also be bent in the X direction or the opposite direction of X. As Figure 5as shown

[0056] By adjusting the waveguide folding depth, it is ensured that the path length d2 that the signal travels between the two slits in the waveguide channel is an integer multiple of λ, so that the surface currents cut by the slits are in phase, and thus the current directions coupled from the slits to the dipole antenna elements are the same. In this example, the length L2 of the dipole element is approximately 0.5λ.

[0057] Adopting the structure shown in this application example, taking the 77 GHz frequency as an example, the length a of the antenna structure in the X direction can be 1.5 mm, meeting the requirement of being less than 1.96 mm (0.5λ).

[0058] In this example, the radiation element 21 is a dipole antenna element. A dipole antenna element includes two metal blocks - the first metal block 211 and the second metal block 212. To obtain a better coupling effect, the two metal blocks are arranged close to the slit 121, for example, respectively arranged at the edges on both sides of the slit 121. The two metal blocks can be symmetrically arranged with the slit as the center. In this example, as Figure 4B shown, the longitudinal cross-section of the metal block is rectangular. In other examples, the longitudinal cross-section of the metal block can be other shapes, such as square, circular, etc. In this example, as Figure 4A shown, the cross-sectional shape of the metal block is rectangular. In other examples, the cross-sectional shape of the metal block can be other shapes, such as square, circular, etc.

[0059] In this example, the dipole antenna element is equivalent to an electric dipole. At this time, the polarization of this electric dipole is in the Y direction, and the antenna pattern in the X direction is a wide beam. The horizontal plane pattern of the folded waveguide dipole antenna array in this application example is as Figure 6 shown. The beam width with a maximum gain of -6 dB can cover ±70°. It can be seen that this dipole antenna array can achieve the characteristics of high gain and wide beam. Since the polarization plane of this dipole is not in the same horizontal plane as the wide beam plane of the pattern, the pattern of the wide beam plane is not easily affected by the surrounding environment and is not prone to jitter. Figure 7 shows a schematic diagram of the wide beam dipole array antenna on a large waveguide plate to observe the change of the pattern. Figure 8 is the comparison of the horizontal plane patterns of the wide beam dipole array antenna on two sizes of waveguide plates. It can be seen from Figure 8 that after the size of the waveguide plate becomes larger, the pattern does not jitter. It can be seen that the antenna structure provided in this embodiment can achieve a pattern with a relatively wide beam. Using this antenna structure as a millimeter-wave radar antenna can not only achieve a relatively wide beam pattern, but also has strong stability, and at the same time has a smaller size, which is beneficial to the layout of a radar system with a small pitch and the stability of radar detection performance.

[0060] The above example is described by taking an antenna structure including four dipole antenna units and three feeding units as an example. In other embodiments, an antenna structure may include at least two dipole antenna units and at least one feeding unit. The above antenna structure may be disposed on a waveguide plate. More than two (including two) antenna structures may be disposed on one waveguide plate to form an array layout of multiple transmitting antennas and multiple receiving antennas, that is, an antenna structure array, so as to improve the angular resolution of the radar system.

[0061] The embodiment of the present disclosure further provides a radar sensor chip, including the antenna structure described in any of the above embodiments. The radar sensor chip, as Figure 9 shown, may include a signal receiving module, a signal transmitting module, and a clock source. Wherein, the signal transmitting module is configured to transmit an electromagnetic wave signal through a transmitting antenna based on a reference frequency provided by a phase-locked loop in the clock source; the signal receiving module uses a receiving antenna to receive an echo formed by being reflected by a target object, and performs down-conversion processing based on the reference frequency provided by the phase-locked loop in the clock source, and generates and outputs an intermediate frequency signal.

[0062] Optionally, in an exemplary embodiment of the present disclosure, the frequency-modulated continuous wave signal is a millimeter wave signal, so that the electronic device can be applied to fields such as autonomous driving, industrial automation, smart home appliances, and security inspection.

[0063] As Figure 10 shown, in an exemplary embodiment, the radar sensor may further include an analog-to-digital conversion module and a signal processing module. Wherein, the signal receiving module generates and outputs an intermediate frequency signal to the analog-to-digital conversion module, and after being processed by the analog-to-digital conversion module, it is transmitted to the signal processing module, and the signal processing module performs signal processing on the digital signal output by the analog-to-digital conversion module.

[0064] Figure 9 and Figure 10 the transmitting antenna and the receiving antenna in

[0065] Exemplarily, the signal transmitting module generates a chirp signal in accordance with a preset continuous frequency modulation method; obtains a radio frequency transmitting signal through frequency multiplication processing, and feeds it to a transmitting antenna to transmit a corresponding detection signal wave. When the detection signal wave is reflected by an object, an echo signal wave is formed. The echo signal wave is converted into a radio frequency receiving signal by a receiving antenna. The signal receiving module is used to perform processing such as down-conversion, filtering, and analog-to-digital conversion on the radio frequency receiving signal by using the radio frequency transmitting signal, so as to output a baseband digital signal representing the difference frequency between the detection signal wave and the echo signal wave. The signal processing module is used to extract measurement information from the baseband digital signal through signal processing and output corresponding measurement data. Among them, the signal processing includes performing digital signal processing calculations such as phase, frequency, and time domain on at least one path of to-be-processed signals provided by at least one path of receiving antennas. The measurement data includes at least one of the following: distance data for representing the relative distance of at least one detected obstacle; speed data for representing the relative speed of at least one detected obstacle; angle data for representing the relative angle of at least one detected obstacle, etc.

[0066] Optionally, the frequency-modulated continuous wave signal is a millimeter wave signal, and the radar sensor may be an AiP millimeter wave radar chip integrated with an antenna. In other embodiments of the present disclosure, the radar sensor may also be other types of radar chips, and the present disclosure does not limit this.

[0067] The millimeter wave radar antenna adopting the antenna structure of the embodiment of the present disclosure has a smaller size, not only has a wide beam characteristic, but also has high directivity pattern stability, is not easily affected by the surrounding environment, and can improve the radar detection performance.

[0068] In an exemplary embodiment, the embodiment of the present disclosure further provides an electronic device including a radar sensor.

[0069] Exemplarily, the electronic device includes: a device body; and a radar sensor as described in the above embodiment provided on the device body. Wherein the device body is a structure that carries radio devices and is signal-connected to the radio devices. The radio devices realize functions such as target detection and / or communication within the range of beam scanning by transmitting and / or receiving radio signals that have been phase-shifted by a phase shifter, so as to provide detection target information and / or communication information to the device body, and further assist or even control the operation of the device body.

[0070] In an alternative embodiment, the electronic device including the device body and the aforementioned at least one radio device may be components and products applied in fields such as smart homes, transportation, smart home appliances, consumer electronics, monitoring, industrial automation, in-cabin detection, and healthcare. For example, the device body may be a smart transportation device (such as a car, bicycle, motorcycle, ship, subway, train, etc.), a security device (such as a camera), a liquid level / flow rate detection device, a smart wearable device (such as a bracelet, glasses, etc.), a smart home appliance (such as a floor cleaning robot, door lock, TV, air conditioner, smart light, etc.), various communication devices (such as a mobile phone, tablet computer, etc.), as well as a barrier gate, smart traffic lights, smart signs, traffic cameras, and various industrial robotic arms (or robots), and may also be various instruments for detecting vital sign parameters and various devices equipped with such instruments, such as in-cabin detection in a car, indoor personnel monitoring, smart medical devices, consumer electronic devices, etc.

[0071] In the description of the embodiments of the present disclosure, it should be noted that the orientation or positional relationship indicated by terms such as "upper", "lower", "one side", "the other side", "one end", "the other end", "edge", "opposite", "four corners", "periphery", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present disclosure and simplifying the description, rather than indicating or implying that the structure referred to has a specific orientation, is constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present disclosure.

[0072] In the description of the embodiments of the present disclosure, unless otherwise clearly specified and limited, the terms "connection", "direct connection", "indirect connection", "fixed connection", "installation", "assembly" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; the terms "installation", "connection", "fixed connection" may be directly connected, or indirectly connected through an intermediate medium, and may be the communication inside two components. For those of ordinary skill in the art, the meanings of the above terms in the present disclosure can be understood according to the circumstances.

[0073] The present disclosure includes and contemplates combinations with features and elements known to those of ordinary skill in the art. The disclosed embodiments, features, and elements of the present disclosure may also be combined with any conventional features or elements to form a unique inventive solution defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive solutions to form another unique inventive solution defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in the present disclosure can be implemented alone or in any suitable combination. Therefore, the embodiments are not subject to other limitations except those made according to the appended claims and their equivalents. In addition, various modifications and changes can be made within the scope of protection of the appended claims.

Claims

1. An antenna structure, characterized in that, Comprising a waveguide feeding structure and a radiation structure arranged on a first surface of the waveguide feeding structure, wherein: The radiation structure includes at least two radiation units, and the radiation units are dipole units; The waveguide feeding structure includes a waveguide channel, and slits communicating with the waveguide channel are respectively arranged at positions corresponding to the radiation units on the first surface. The waveguide channel between two adjacent slits has a bending structure, and the length of the waveguide channel between the two adjacent slits is such that the current directions on two adjacent radiation units adjacent to the two slits are the same.

2. The antenna structure according to claim 1, wherein The length of the waveguide channel with a bending structure between two adjacent slits is an integral multiple of the air wavelength.

3. The antenna structure according to claim 1, characterized in that, The bending structure of the waveguide channel between two adjacent slits is in a U shape.

4. The antenna structure according to claim 1, wherein The waveguide feeding structure includes a body and a top cover, the body and the top cover form the waveguide channel, and the slits are arranged at positions corresponding to the radiation units on the first surface of the top cover, and one radiation unit is arranged at each slit.

5. The antenna structure according to claim 1, wherein Each radiation unit includes two radiation branches, and the two radiation branches are arranged on the first surface of the waveguide feeding structure and symmetrically arranged on both sides of the slit with the slit as the axis of symmetry.

6. The antenna structure according to claim 5, characterized in that, The radiation branch is in a strip shape, the extending direction of the strip-shaped radiation branch is a first direction, the extending direction of the slit is a second direction, and the first direction is perpendicular to the second direction.

7. The antenna structure according to claim 5, wherein The center lines of the strip-shaped radiation branches of all radiation units coincide in the extending direction.

8. The antenna structure according to claim 5, characterized in that, The distance between two adjacent radiation units is λ / 2, where λ is the air wavelength.

9. The antenna structure according to claim 5, characterized in that, The center distance between two adjacent slits is less than λ and greater than 0.5λ, where λ is the air wavelength.

10. The antenna structure according to claim 5, wherein The maximum distance between two radiation branches in one radiation unit is λ / 2, where λ is the air wavelength.

11. A radar sensor, characterized in that, Comprising the antenna structure according to any one of claims 1-10.

12. An electronic device, characterized in that, Comprising the radar sensor according to claim 11.

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