Waveguide antenna, radio frequency device and radar

Abstract

The embodiment of the utility model relates to the technical field of semiconductors, and discloses a waveguide antenna, a radio frequency device and a radar, and the waveguide antenna comprises at least one antenna lower waveguide and a radiation part located on each antenna lower waveguide. The waveguide below the antenna is formed by splicing a first half waveguide and a second half waveguide to form a first splicing gap, and the first splicing gap forms a center line of the side wall of the wide edge of the waveguide below the antenna; and the radiation part is arranged on the narrow side wall of the waveguide below the antenna. According to the scheme, signal leakage can be effectively prevented by adopting a mode of cutting at the center line position of the side wall of the waveguide wide edge at the waveguide antenna part, the cutting mode is simple in process implementation, the machining limitation is reduced, and the method can be applied to waveguide channels with small spacing.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of semiconductor technology, and in particular to a waveguide antenna, a radio frequency device and a radar. Background Art

[0002] With the development of autonomous driving technology, the performance of millimeter-wave radar needs to be further improved. Compared with the board-level antenna currently designed on the printed circuit board (PCB), the external waveguide antenna can further reduce the feeder loss and improve the performance of the millimeter-wave radar module. Because the external waveguide antenna has built-in waveguide routing, it usually needs to be divided into several parts for processing and then assembled and installed later. Due to the influence of the processing technology, the waveguide antenna cannot fit perfectly during assembly, and there will be gaps at the joints. The existence of gaps will cause RF signal leakage, resulting in reduced antenna gain and deteriorated radiation patterns.

[0003] At present, in order to prevent signal leakage during assembly, waveguide antennas usually use gap waveguide structures to prevent signal leakage. The gap waveguide forms an electromagnetic band gap (EBG) without physical contact under certain conditions through a periodic electromagnetic structure, and uses the electromagnetic bandgap characteristics of EBG to build a waveguide or shielding structure. In practical applications, a gap waveguide structure can be formed by placing periodically arranged columns around the waveguide. In order to better achieve the effect of the electromagnetic bandgap, at least two rows of columns are usually required, so the area occupied is large. For antenna systems with small pitch arrays, the processing feasibility of this solution is limited. Utility Model Content

[0004] The purpose of the embodiments of the present application is to provide a waveguide antenna, a radio frequency device and a radar. In the waveguide antenna part, cutting at the midline position of the side wall of the wide side of the waveguide can effectively prevent signal leakage, and the cutting method is simple to implement, which reduces the mechanical processing restrictions and can be applied to waveguide channels with small spacing.

[0005] To solve the above technical problems, an embodiment of the present application provides a waveguide antenna, comprising: at least one waveguide below the antenna, and a radiating portion located on the waveguide below each antenna; the waveguide below the antenna is formed by splicing a first half waveguide and a second half waveguide to form a first splicing gap, and the first splicing gap forms the center line of the wide side wall of the waveguide below the antenna; the radiating portion is arranged on the narrow side wall of the waveguide below the antenna.

[0006] Compared with the related art, the waveguide antenna of the embodiment of the present application includes at least one waveguide below the antenna, and a radiating portion located on the waveguide below each antenna; since each waveguide below the antenna is formed by splicing the first half waveguide and the second half waveguide to form a first splicing gap, and the first splicing gap forms the center line of the wide side wall of the waveguide below the antenna, according to the surface current distribution of the air waveguide, the center line of the wide side wall along the extension direction of the waveguide is the direction of the surface current, that is, the cutting line of the first splicing gap on the wide side wall is parallel to the surface current. Since the cutting line does not cut the surface current, the signal leakage at the splicing point can be effectively reduced. At the same time, this cutting method is simple to implement, reduces mechanical processing restrictions, and can be applied to waveguide channels with small spacing. In addition, the first splicing gap is set on the wide side wall of the waveguide below the antenna, and the radiating portion is set on the narrow side wall of the waveguide below the antenna, so that the splicing process and signal radiation do not affect each other.

[0007] In some embodiments, the radiation portion includes at least two radiation slots arranged along the extension direction, and the current directions in the at least two radiation slots are the same.

[0008] In some embodiments, the narrow side wall of the waveguide below the antenna is bent back and forth multiple times along the plane where it is located, and the at least two radiation slots are respectively located at the bends of the narrow side wall.

[0009] In some embodiments, the radiation slots are located at bends in the narrow side walls that are bent in the same direction.

[0010] In some embodiments, the radiation slot is arranged to protrude from the narrow side wall surface, and / or the edge of the radiation slot is flush with the narrow side wall surface.

[0011] In some embodiments, the distance between two adjacent radiation slots is [0.5λ, 0.8λ], where λ is the working wavelength of the signal transmitted by the waveguide antenna.

[0012] In some embodiments, the waveguide antenna further includes at least one feeder waveguide, wherein the feeder waveguides are respectively connected to corresponding waveguides below the antenna.

[0013] In some embodiments, the feeder waveguide is formed by splicing a third half waveguide and a fourth half waveguide to form a second splicing gap, and the second splicing gap forms a center line of the wide side wall of the feeder waveguide; the third half waveguide is connected to the first half waveguide, and the fourth half waveguide is connected to the second half waveguide.

[0014] In some embodiments, the waveguide antenna includes at least two waveguides below the antenna, and the waveguide antenna also includes a power divider and a feeder waveguide, at least two waveguides below the antenna are connected to the power divider, and the power divider is connected to the feeder waveguide.

[0015] In some embodiments, the power divider is formed by splicing the fifth half waveguide and the sixth half waveguide to form a third splicing gap, the power divider includes three waveguide ports, and the third splicing gap forms the center line of the wide side wall of the power divider, two half waveguide ports in the fifth half waveguide are respectively connected to the first half waveguide of the two waveguides below the antenna, and two half waveguide ports in the sixth half waveguide are respectively connected to the second half waveguide of the two waveguides below the antenna; the feeder waveguide is formed by splicing the third half waveguide and the fourth half waveguide to form a second splicing gap, and the second splicing gap forms the center line of the wide side wall of the feeder waveguide; the third half waveguide is connected to the remaining half waveguide port of the fifth half waveguide, and the fourth half waveguide is connected to the remaining half waveguide port of the sixth half waveguide.

[0016] In some embodiments, at least two waveguides below the antenna are arranged in parallel along the transmission direction of the waveguide below the antenna, and the current directions of two adjacent waveguides below the antenna in the same cross-section are opposite.

[0017] In some embodiments, at least two of the waveguides below the antenna are arranged in parallel.

[0018] Another aspect of an embodiment of the present application provides a radio frequency device, including: a waveguide antenna as described in any of the above embodiments.

[0019] On the other hand, an embodiment of the present application provides a radar, including: the radio frequency device as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0021] Figure 1 This is a schematic diagram of the surface current of a conventional air waveguide;

[0022] Figure 2 The main view of the waveguide antenna provided according to one embodiment of the present application Figure 1 ;

[0023] Figure 3 A top view of a waveguide antenna provided according to an embodiment of the present application Figure 1 ;

[0024] Figure 4 A top view of a waveguide antenna provided according to an embodiment of the present application Figure 2 ;

[0025] Figure 5The main view of the waveguide antenna provided according to one embodiment of the present application Figure 2 ;

[0026] Figure 6 A top view of a waveguide antenna provided according to an embodiment of the present application Figure 3 ;

[0027] Figure 7 The main view of the waveguide antenna provided according to one embodiment of the present application Figure 3 . DETAILED DESCRIPTION

[0028] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, each embodiment of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in each embodiment of the present application, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can also be implemented. The division of the following embodiments is for the convenience of description, and the specific implementation of the present application should not be construed as any limitation, and the various embodiments can be combined and referenced with each other without contradiction.

[0029] According to electromagnetic field theory, for TE10 wave, if Figure 1 As shown in the figure, there are two current components, longitudinal and transverse, on the wide side wall of the waveguide (the side wall where the wide side a is located). The magnitude of the transverse component is cosine distributed along the wide side wall and is zero at the center. The longitudinal current is sinusoidally distributed along the wide side wall and is the largest at the center. On the narrow side wall of the waveguide (the side wall where the narrow side b is located), there is only transverse current, which is evenly distributed along the narrow side wall. When the gap is parallel to the current line, an excitation electric field cannot be established in the gap area. Such a gap does not have the ability to radiate because it cannot be excited, so it is called a non-radiating gap, such as gap 1; on the contrary, when the gap is perpendicular to the current line, an excitation electric field is established in the gap area. Such a gap has the ability to radiate because it is excited, so it is called a radiating gap, such as gap 2. It can be seen from this that when the wide side wall of the waveguide is cut in the middle (along the extension direction of the waveguide by default), the signal cannot be radiated outward, and the electromagnetic signal in the waveguide can still be transmitted forward. Based on this electromagnetic principle, the present application proposes that when a waveguide under the antenna is formed by splicing, the center line of the wide side wall of the waveguide under the antenna is used as the splicing gap formed when two half waveguides are spliced, thereby effectively preventing signal leakage at the splicing point of the waveguide under the antenna after splicing.

[0030] One embodiment of the present application relates to a waveguide antenna, such as Figure 2 As shown, the waveguide antenna comprises: at least one waveguide 1 below the antenna, and a radiating portion 2 ( Figure 2A schematic diagram of a waveguide 1 below an antenna is given as an example).

[0031] Each waveguide 1 below the antenna is spliced ​​by a first half waveguide 11 and a second half waveguide 12 to form a first splicing gap G1, and the first splicing gap G1 forms a center line of a wide side wall S1 of the waveguide 1 below the antenna.

[0032] Figure 2 In the figure, the waveguide 1 below the antenna is hollow inside, and the cross section of its side wall is rectangular, wherein the side wall where the wide side of the rectangle (length a) is located is called the "wide side wall", and the side wall where the narrow side of the rectangle (length b) is located is called the "narrow side wall". Figure 2 As shown, the waveguide 1 below the antenna has two wide side walls and two narrow side walls, wherein S1 is a wide side wall of the waveguide 1 below the antenna, and S2 is a narrow side wall of the waveguide 1 below the antenna.

[0033] The waveguide 1 below the antenna is divided into two parts by taking the center line of the two wide side walls of the waveguide 1 below the antenna as a dividing line, namely the first half waveguide 11 and the second half waveguide 12. In the process of processing the waveguide 1 below the antenna, the first half waveguide 11 and the second half waveguide 12 can be processed separately first, and then the two parts are spliced ​​along the above-mentioned dividing line to form a complete waveguide 1 below the antenna, and the first splicing gap G1 generated by the splicing forms the center line of the wide side wall S1 of the waveguide 1 below the antenna.

[0034] According to the surface current distribution of the air waveguide, the center line of the wide side wall of the waveguide 1 below the antenna along the extension direction of the waveguide is the direction of the surface current, that is, the cutting line of the first splicing gap G1 on the wide side wall is parallel to the surface current. Since the cutting line does not cut the surface current, the signal leakage at the splicing point can be effectively reduced; when the first half waveguide 11 and the second half waveguide 12 are processed, no special bonding operation is required, and only the fixing screws need to be placed to achieve splicing. The cutting method used in this embodiment is simple to implement and reduces the mechanical processing restrictions. The waveguide antenna formed can be applied to waveguide channels with small spacing.

[0035] In this embodiment, although the cross sections of the side wall of the waveguide 1 below the antenna are rectangular, its structure along the extension direction of the waveguide can be straight, curved or even bent multiple times, which is not limited in this embodiment.

[0036] The radiating portion 2 is arranged on the narrow side wall of the waveguide 1 below the antenna.

[0037] In order to ensure that the waveguide 1 below the antenna can be cut along the center line of the wide side wall, the radiating portion 2 needs to be arranged on the narrow side wall of the waveguide 1 below the antenna, similar to the arrangement of the slit 2. For example, the radiating portion 2 can be arranged on the narrow side wall (narrow side wall S2) of the waveguide 1 below the antenna located on the first half waveguide 11, and / or on the narrow side wall of the waveguide 1 below the antenna located on the second half waveguide 12. Since the surface current lines on the narrow side wall are parallel to the narrow side, the slit of the radiating portion 2 is arranged on the narrow side wall and perpendicular to the current lines, and an excitation electric field can be established in the slit area. Such a slit has radiation ability due to the excitation, and thus can complete the signal radiation well. In addition, the first splicing slit G1 is arranged on the wide side wall of the waveguide 1 below the antenna, and the radiating portion 2 is arranged on the narrow side wall of the waveguide 1 below the antenna, so that the splicing process and signal radiation do not affect each other.

[0038] In some embodiments, Figure 2 As shown, the radiation portion 2 may include at least two radiation slots 21 arranged along the extension direction, and the current directions in the at least two radiation slots 21 are the same.

[0039] Among them, the extension direction of each radiation slot 21 should be non-parallel to the narrow side of the waveguide 1 below the antenna. The preferred solution is to be perpendicular to the narrow side, that is, the radiation slot 21 is perpendicular to the current line on the side wall of the narrow side, so as to establish a maximum excitation electric field in the slot area. In this way, the radiation slot 21 has the radiation ability to radiate signals outward due to the excitation.

[0040] When the waveguide 1 below the antenna is set as a conventional rectangular waveguide (refer to Figure 1 ), since the current on the narrow side wall of the waveguide 1 below the antenna is reversed every 0.5λ (λ is the working wavelength of the signal transmitted by the waveguide antenna), in order to ensure that the current directions of each radiation slot 21 are in phase, the spacing between adjacent radiation slots 21 should be taken as λ or an integer multiple of λ. Of course, in order to shorten the spacing between adjacent radiation slots 21, the extension path of the waveguide antenna can also be changed, such as changing from a traditional straight path to a curved path or a broken line path, so that the spacing between adjacent radiation slots 21 can be adjusted while ensuring that the current directions of each radiation slot 21 are in phase. This embodiment does not limit the form of the extension path of the waveguide antenna.

[0041] For example, in some embodiments, Figure 2 , Figure 3 As shown in , the narrow side wall (such as the narrow side wall S2) of the waveguide 1 below the antenna is bent back and forth multiple times along the plane where it is located, and the at least two radiation slots 21 can be respectively located at the bending positions of the narrow side wall.

[0042] like Figure 3In the figure, two narrow side walls S2 of the waveguide 1 under the two antennas are shown. The two narrow side walls S2 are on the plane where they are located and are bent back and forth many times on both sides of the extension direction of the waveguide antenna. The two radiation slots 21 arranged on the narrow side wall S2 on the left side can be located at the bending on the right side of the extension direction of the waveguide antenna; the two radiation slots 21 arranged on the narrow side wall S2 on the right side can be located at the bending on the left side of the extension direction of the waveguide antenna. In addition, at least two radiation slots 21 located on the narrow side wall S2 can also be located at the bending on the left side of the at least two radiation slots 21, and the radiation slots 21 can be located at the bending on the right side of the at least two radiation slots 21; each radiation slot 21 can be arranged continuously at the bending, or it can be arranged discontinuously with at least one bending interval. In this embodiment, the arrangement of each radiation slot 21 at the bending is not limited, as long as the current directions of each radiation slot 21 are in phase.

[0043] In some embodiments, the radiation slots 21 are preferably located at the bending positions of the narrow side walls that are bent in the same direction.

[0044] like Figure 3 As shown in the figure, on the narrow side wall S2 on the left side, the two radiation slots 21 are both located at the bending part on the right side of the extension direction of the waveguide antenna, and the bending direction can be regarded as facing the left side; on the narrow side wall S2 on the right side, the two radiation slots 21 are both located at the bending part on the left side of the extension direction of the waveguide antenna, and the bending direction can be regarded as facing the right side. By setting each radiation slot 21 at the bending part of the narrow side wall that bends in the same direction, the shape and size of the reciprocating bend of the narrow side wall can be set more regularly, so that each radiation slot 21 has the same state, thereby better ensuring that the current direction of each radiation slot 21 is in phase.

[0045] In some embodiments, the radiation slot 21 is arranged to protrude from the surface of the narrow side wall, and / or the edge of the radiation slot 21 is flush with the surface of the narrow side wall.

[0046] For example Figure 2 In the embodiment, for the convenience of process processing, the radiation slot 21 can be protruded from the outer surface of the narrow side wall S2; or, for the purpose of process flexibility, the radiation slot 21 can be flush with the outer surface of the narrow side wall S2; or, in order to take into account the convenience and flexibility of the process, all the radiation slots 21 can also be partially "protruding" and partially "flush", which is not limited in this embodiment.

[0047] In some embodiments, the distance between two adjacent radiation slots 21 is [0.5λ, 0.8λ], where λ is the working wavelength of the signal transmitted by the waveguide antenna.

[0048] When the waveguide 1 below the antenna is set as a conventional rectangular waveguide (refer to Figure 1), since the current on the narrow side wall of the waveguide 1 below the antenna is reversed every 0.5λ (the working wavelength of the signal transmitted by the waveguide antenna), in order to ensure that the current directions of the radiation slots 21 are in phase, the spacing between adjacent radiation slots 21 should be taken as λ or an integer multiple of λ, at this time, grating lobes will appear in the slot array. By modifying the extension path of the waveguide 1 below the antenna, such as setting the waveguide 1 below the antenna as follows Figure 3 The reciprocating bending structure shown, as well as the use of high-order modes, can reduce the distance between two adjacent radiation slots 21. It is only necessary to ensure that the spacing of the same-phase currents in two adjacent radiation slots 21 is within the range of [0.5λ, 0.8λ] to achieve a wide-beam low-grating-lobe slot array.

[0049] The above is an explanation of the related structures of the waveguide 1 under each antenna and the radiating portion 2 arranged thereon included in the waveguide antenna in this embodiment. Based on any of the above embodiments, the waveguide antenna in this embodiment may further include a feeder waveguide, or a combined structure of a feeder waveguide and a power divider. The following describes these two supplementary waveguide antenna structures in detail.

[0050] In some embodiments, Figure 4 As shown, the above-mentioned waveguide antenna may further include at least one feeder waveguide 3, wherein the feeder waveguide 3 is respectively connected to the corresponding waveguide 1 below the antenna.

[0051] like Figure 5 In the figure, one end of each waveguide 1 under the antenna is connected to a corresponding feeder waveguide 3. The feeder waveguide 3 is hollow inside, and the cross section of the side wall of the feeder waveguide 3 is a rectangle. The size of the rectangle is the same as the size of the rectangle of the cross section of the side wall of the waveguide 1 under the antenna, that is, the length of the wide side of the rectangle is a, and the length of the narrow side is b. In this way, when the feeder waveguide 3 is connected to the waveguide 1 under the antenna, the size of the connected waveguide opening can be consistent, thereby forming a tightly connected signal transmission path. The length of the feeder waveguide 3 is longer than that of the waveguide 1 under the antenna, and the extension path can be extended along a straight line, a curve or a bend line. It mainly feeds the radio frequency signal generated in the radar chip into the waveguide 1 under the antenna, and then radiates it through the radiating part 2, or transmits the signal received by the radiating part 2 back to the radar chip through the signal transmission path formed with the waveguide 1 under the antenna for signal processing.

[0052] During the process of processing, the feeder waveguide 3 and the waveguide 1 under the antenna can be integrally formed to avoid signal leakage caused by a gap when the feeder waveguide 3 is connected to the waveguide 1 under the antenna. At the same time, the processing technology can be simplified. The feeder waveguide and the waveguide under the antenna can be processed separately and then connected. The connection methods include but are not limited to bonding, screw fixing, etc.

[0053] In some embodiments, the feeder waveguide 3 is spliced ​​by the third half waveguide 31 and the fourth half waveguide 32 to form a second splicing gap G2, and the second splicing gap G2 forms the center line of the wide side wall of the feeder waveguide 3; the third half waveguide 31 is connected to the first half waveguide 11, and the fourth half waveguide 32 is connected to the second half waveguide 12.

[0054] Figure 5 In the figure, the two wide side walls and the two narrow side walls of the waveguide 1 below the antenna are respectively connected to the two wide side walls and the two narrow side walls of the feeder waveguide 3, wherein S3 is a wide side wall of the feeder waveguide 3, and S4 is a narrow side wall of the feeder waveguide 3. The feeder waveguide 3 is divided into two parts, namely the third half waveguide 31 and the fourth half waveguide 32, by taking the midline of the two wide side walls of the feeder waveguide 3 as the dividing line, wherein the first half waveguide 11 is connected to the third half waveguide 31, and the second half waveguide 12 is connected to the fourth half waveguide 32. In the process of processing the feeder waveguide 3, since the waveguide 1 below the antenna needs to be connected to the feeder waveguide 3, the one-piece structure of the first half waveguide 11 and the third half waveguide 31, and the one-piece structure of the second half waveguide 12 and the fourth half waveguide 32 can be processed separately first, and then the two parts of the structure are spliced ​​from the dividing line to form the feeder waveguide 3 while forming the waveguide 1 below the antenna, and the second splicing gap G2 generated by the splicing forms the center dividing line of the feeder waveguide 3.

[0055] According to the surface current distribution of the air waveguide, the bisecting line of the wide side wall of the feeder waveguide 3 along the waveguide extension direction is the direction of the surface current, that is, the cutting line of the second splicing gap G2 on the wide side wall is parallel to the surface current. Since the cutting line does not cut the surface current, the signal leakage at the splicing point can be effectively reduced; when the third half waveguide 31 and the fourth half waveguide 32 are processed, no special bonding operation is required, and only the fixing screws need to be placed to achieve splicing. The cutting method used in this embodiment is simple to implement, reduces the mechanical processing restrictions, and the formed waveguide antenna can be applied to waveguide channels with small spacing.

[0056] Compared to Figure 4 , Figure 5 In addition to the solution shown in the figure where the waveguide 1 under each antenna is directly connected to the feeder waveguide 3, the present application also proposes a solution whereby the waveguides 1 under two antennas are connected to one feeder waveguide 3 by introducing a power divider.

[0057] In some embodiments, Figure 6 The waveguide antenna includes at least two waveguides 1 below the antenna. The waveguide antenna also includes a power divider 4 and a feeder waveguide 3. At least two waveguides 1 below the antenna are connected to the power divider 4, and the power divider 4 is connected to the feeder waveguide 3.

[0058] like Figure 6In the embodiment, the power divider 4 may include but is not limited to two waveguide ports, one of which is connected to the feeder waveguide 3, and each of the remaining waveguide ports is connected to a waveguide 1 below the antenna, wherein the structure of the feeder waveguide 3 has been described in the above embodiment and will not be described in detail here. Figure 7 As shown, the power divider 4 is hollow inside, and the cross section of each waveguide opening of the power divider 4 is a rectangle. The size of the rectangle is the same as the size of the rectangle of the cross section of the side wall of the waveguide 1 below the antenna and the feeder waveguide 3, that is, the length of the wide side of the rectangle is a, and the length of the narrow side is b. In this way, when the power divider 4 is connected to the waveguide 1 below the antenna and the feeder waveguide 3 respectively, the sizes of the connected waveguide openings can be consistent, thereby forming a tightly connected signal transmission path. The length of the path extending from the end of the power divider 4 connected to the feeder waveguide 3 to each waveguide 1 below the antenna is different, such as Figure 6 As shown in the figure, after the power divider 4 is led out from one end of the feeder waveguide 3, it is connected to the two waveguides 1 under the antenna through two branch waveguide paths, wherein the length of the branch waveguide path on the right is greater than the length of the branch waveguide path on the left. This arrangement allows the current directions of the two parallel waveguides 1 under the antenna to be different on the same cross section. The length of each branch waveguide path can be flexibly set, and the path can extend along a straight line, a curve or a meander line. Its function is to split the signal in the feeder waveguide 3 into two signals with the same power ratio and transmit them to the two waveguides 1 under the antenna respectively, or to combine the two signals in the waveguide 1 under the antenna and transmit them back to the feeder waveguide 3.

[0059] During the process of processing, the feeder waveguide 3, the power divider 4 and the waveguide 1 below the antenna can be integrally formed to avoid signal leakage caused by gaps when connecting the feeder waveguide 3, the power divider 4 and the waveguide 1 below the antenna, and the processing technology can also be simplified.

[0060] In some embodiments, Figure 7 As shown, the power divider 4 is spliced ​​by the fifth half waveguide 41 and the sixth half waveguide 42 to form a third splicing gap G3. The power divider 4 includes three waveguide ports, and the third splicing gap G3 forms the center line of the wide side wall of the power divider 4. The two half waveguide ports in the fifth half waveguide 41 are respectively connected to the first half waveguide 11 of the waveguide 1 under the two antennas, and the two half waveguide ports in the sixth half waveguide 42 are respectively connected to the second half waveguide 12 of the waveguide under the two antennas.

[0061] Figure 7In the figure, the two wide side walls and the two narrow side walls of the waveguide 1 below each antenna are respectively connected to the two wide side walls and the two narrow side walls of the corresponding waveguide opening in the power divider 4, and the two wide side walls and the two narrow side walls of the feeder waveguide 3 are respectively connected to the two wide side walls and the two narrow side walls of the remaining waveguide opening in the power divider 4. The power divider 4 is divided into two parts, namely the fifth half waveguide 41 and the sixth half waveguide 42, by taking the midline of the two wide side walls where each waveguide opening of the power divider 4 is located as the dividing line, wherein the two half waveguide openings in the fifth half waveguide 41 are respectively connected to the first half waveguide 11 of the waveguides 1 below the two antennas, and the two half waveguide openings in the sixth half waveguide 42 are respectively connected to the second half waveguide 12 of the waveguides below the two antennas. In the process of processing the power divider 4, since the waveguide 1 below the antenna needs to be connected to the power divider 4, the one-piece structure of the first half waveguide 11 and the fifth half waveguide 41, and the one-piece structure of the second half waveguide 12 and the sixth half waveguide 42 can be processed separately first, and then the two parts of the structure are spliced ​​from the dividing line to form the waveguide 1 below the antenna and the power divider 4 at the same time, and the third splicing gap G3 forms the center dividing line of the power divider 4.

[0062] According to the surface current distribution of the air waveguide, the dividing line of the wide side wall where the three waveguide ports of the power divider 4 are located along the waveguide extension direction is the direction of the surface current, that is, the cutting line of the third splicing gap G3 on the wide side wall is parallel to the surface current. Since the cutting line does not cut the surface current, the signal leakage at the splicing point can be effectively reduced; when the fifth half waveguide 41 and the sixth half waveguide 42 are processed, no special bonding operation is required, and only the fixing screws need to be placed to achieve splicing. The cutting method used in this embodiment is simple to implement, reduces the mechanical processing restrictions, and the formed waveguide antenna can be applied to waveguide channels with small spacing.

[0063] The feeder waveguide 3 in this embodiment is formed by splicing the third half waveguide 31 and the fourth half waveguide 32 to form a second splicing gap G2, and the second splicing gap G2 forms the center line of the wide side wall of the feeder waveguide 3; the third half waveguide 31 is connected to the remaining half waveguide port of the fifth half waveguide 41, and the fourth half waveguide 32 is connected to the remaining half waveguide port of the sixth half waveguide 42.

[0064] Among them, the relevant description that the feed waveguide 3 is formed by splicing the third half waveguide 31 and the fourth half waveguide 32 can be found in the above embodiment, which will not be repeated here. It should be noted that the feed waveguide 3 in this embodiment is connected to the power divider 4. In the process of processing the feed waveguide 3, since the waveguide 1 below the antenna, the power divider 4, and the feed waveguide 3 need to be connected in sequence, the one-piece structure of the first half waveguide 11, the third half waveguide 31 and the fifth half waveguide 41, and the one-piece structure of the second half waveguide 12, the fourth half waveguide 32 and the sixth half waveguide 42 can be processed separately first, and then these two parts of the structure are spliced ​​from the dividing line to simultaneously form the waveguide 1 below the antenna, the power divider 4 and the feed waveguide 3, and the second splicing gap G2 forms the center dividing line of the feed waveguide 3. At the same time, the first splicing gap G1, the third splicing gap G3 and the second splicing gap G2 are interconnected in sequence to form a gap. During the splicing process, no special bonding operation is required, and splicing can be achieved by simply placing fixing screws. The cutting method used in this embodiment is simple to implement and reduces mechanical processing restrictions. The formed waveguide antenna can be applied to waveguide channels with small spacing.

[0065] In some embodiments, in at least two waveguides 1 below the antenna connected to the same power divider 4, the at least two waveguides 1 below the antenna are arranged in parallel along the transmission direction of the waveguide 1 below the antenna, and the current directions of two adjacent waveguides 1 below the antenna are opposite in the same cross-section.

[0066] For example Figure 6 As shown in , two waveguides 1 under the antenna are arranged in parallel along the transmission direction of the waveguide 1 under the antenna. Due to the introduction of the power divider 4, the lengths of the branch waveguide paths from the bifurcation position of the power divider 4 to the two waveguides 1 under the antenna are different, so that the path lengths of the feeder waveguide 3 to the two waveguides 1 under the antenna are different. By reasonably setting the lengths of the two branch waveguide paths, a 180° phase change can be achieved on the narrow side walls of the two waveguides 1 under the antenna at the same cross section, that is, after passing through the power divider 4, the currents of the two parallel waveguides 1 under the antenna on the same horizontal line are in anti-phase. Therefore, the radiation slots 21 can be placed at intervals of about 0.5λ, thereby realizing an in-phase slot radiation array.

[0067] In some embodiments, in at least two waveguides 1 below the antenna connected to the same power divider 4 , the at least two waveguides 1 below the antenna are arranged in parallel.

[0068] In summary, the waveguide antenna in this embodiment has the following technical effects:

[0069] Since the waveguide 1 below the antenna, the feeder waveguide 3 and the power divider 4 can be divided from the center line of their respective wide side walls to form two sets of integrated half-waveguide structures, when the two sets of half-waveguide structures are spliced ​​along the dividing line, it can be ensured that the signal leakage at the splicing gap is small;

[0070] When two sets of half-waveguide structures are spliced ​​along the dividing line, no special bonding operation is required, and splicing can be achieved by simply placing fixing screws. The cutting method adopted is simple to implement and reduces mechanical processing restrictions. The formed waveguide antenna can be applied to waveguide channels with small spacing.

[0071] The power divider 4 can make the currents in the waveguides 1 below the two parallel antennas on the same horizontal line be in opposite phases, thereby realizing a small-pitch in-phase slot radiation array.

[0072] Another embodiment of the present application further provides a radio frequency device, including: a waveguide antenna as described in any of the above embodiments.

[0073] Another embodiment of the present application further provides a radar, including: the radio frequency device as described in the above embodiment.

[0074] The radar is used to transmit a frequency modulated continuous wave signal based on a reference frequency through a transmitting antenna, and to receive an echo formed by reflection from a target object using a receiving antenna, and to perform down-conversion processing based on the transmitted radio frequency signal to generate and output an intermediate frequency signal. The radar is also used to convert the intermediate frequency signal into a digital signal and then perform signal processing.

[0075] Optionally, in some embodiments, the frequency modulated continuous wave signal is a millimeter wave signal, so that the electronic device equipped with the radar can be applied to the fields of autonomous driving, industrial automation, smart home appliances, and security inspection. The radar can be an AiP millimeter wave radar chip with an integrated antenna.

[0076] For example, the radar generates a chirp signal according to a preset continuous frequency modulation mode; obtains a radio frequency transmission signal through frequency multiplication processing, and feeds it to the transmitting antenna to transmit the 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 the receiving antenna. The radar uses the radio frequency transmission signal to down-convert, filter and other processes the radio frequency receiving signal, and then performs analog-to-digital conversion processing to output a baseband digital signal representing the difference frequency between the detection signal wave and the echo signal wave. Then, measurement information is extracted from the baseband digital signal through signal processing, and measurement data is output. Among them, the signal processing includes performing digital signal processing calculations such as phase, frequency, and time domain on at least one signal to be processed provided by at least one receiving antenna. 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.

[0077] In some embodiments, the present embodiment also provides an electronic device including the aforementioned radar.

[0078] In some embodiments, the electronic device includes: a device body; and electronic devices such as radars in the above embodiments arranged on the device body. The device body is a structure that carries a radio device and is connected to the radio device signal. The radio device transmits and / or receives a radio signal that has been phase-shifted by a phase shifter to achieve functions such as target detection and / or communication within the range of beam scanning, so as to provide the device body with detection target information and / or communication information, thereby assisting or even controlling the operation of the device body.

[0079] In some embodiments, the electronic device including the device body and the aforementioned at least one radio device may be a component or product used in fields such as smart housing, transportation, smart home, consumer electronics, monitoring, industrial automation, in-cabin detection, and health care. For example, the device body may be intelligent transportation equipment (such as automobiles, bicycles, motorcycles, ships, subways, trains, etc.), security equipment (such as cameras), liquid level / flow rate detection equipment, intelligent wearable devices (such as bracelets, glasses, etc.), smart home equipment (such as sweeping robots, door locks, televisions, air conditioners, smart lights, etc.), various communication devices (such as mobile phones, tablet computers, etc.), and gates, intelligent traffic lights, intelligent signs, traffic cameras, and various industrialized mechanical arms (or robots), etc. It may also be various instruments for detecting life characteristic parameters and various equipment equipped with the instruments, such as in-cabin detection of automobiles, indoor personnel monitoring, intelligent medical equipment, consumer electronic equipment, etc.

[0080] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present application, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. A waveguide antenna, characterized in that: include: at least one waveguide below the antenna, and a radiating portion located on each waveguide below the antenna; The waveguide below the antenna is spliced ​​by a first half waveguide and a second half waveguide to form a first splicing gap, and the first splicing gap forms a center line of the wide side wall of the waveguide below the antenna; The radiating portion is arranged on the narrow side wall of the waveguide below the antenna.

2. The waveguide antenna according to claim 1, characterized in that: The radiation portion includes at least two radiation slots arranged along the extension direction, and the current directions in the at least two radiation slots are the same.

3. The waveguide antenna according to claim 2, characterized in that: The narrow side wall of the waveguide below the antenna is bent back and forth multiple times along the plane where it is located, and the at least two radiation slots are respectively located at the bending positions of the narrow side wall.

4. The waveguide antenna according to claim 3, characterized in that: The radiation slots are located at the bending positions of the narrow side walls that are bent in the same direction.

5. The waveguide antenna according to claim 3, characterized in that: The radiation slot is arranged to protrude from the surface of the narrow side wall, and / or the edge of the radiation slot is flush with the surface of the narrow side wall.

6. The waveguide antenna according to claim 2, characterized in that: The distance between two adjacent radiation slots is [0.5λ, 0.8λ], where λ is the working wavelength of the signal transmitted by the waveguide antenna.

7. The waveguide antenna according to any one of claims 1 to 6, characterized in that: The waveguide antenna further includes at least one feeder waveguide, wherein the feeder waveguides are respectively connected to corresponding waveguides below the antenna.

8. The waveguide antenna according to claim 7, characterized in that: The feeder waveguide is formed by splicing the third half waveguide and the fourth half waveguide to form a second splicing gap, and the second splicing gap forms a center line of the wide side wall of the feeder waveguide; The third half waveguide is connected to the first half waveguide, and the fourth half waveguide is connected to the second half waveguide.

9. The waveguide antenna according to any one of claims 1 to 6, characterized in that: The waveguide antenna includes at least two waveguides below the antenna, and the waveguide antenna also includes a power divider and a feeder waveguide, at least two waveguides below the antenna are connected to the power divider, and the power divider is connected to the feeder waveguide.

10. The waveguide antenna according to claim 9, characterized in that: The power divider is formed by splicing a fifth half waveguide and a sixth half waveguide to form a third splicing gap, the power divider includes three waveguide ports, and the third splicing gap forms a midline of a wide side wall of the power divider, two half waveguide ports in the fifth half waveguide are respectively connected to the first half waveguide of the two waveguides below the antenna, and two half waveguide ports in the sixth half waveguide are respectively connected to the second half waveguide of the two waveguides below the antenna; The feeder waveguide is formed by splicing the third half waveguide and the fourth half waveguide to form a second splicing gap, and the second splicing gap forms the center line of the wide side wall of the feeder waveguide; the third half waveguide is connected to the remaining half waveguide port of the fifth half waveguide, and the fourth half waveguide is connected to the remaining half waveguide port of the sixth half waveguide.

11. The waveguide antenna according to claim 10, characterized in that: At least two waveguides below the antenna are arranged in parallel along the transmission direction of the waveguide below the antenna, and the current directions of two adjacent waveguides below the antenna in the same cross section are opposite.

12. The waveguide antenna according to claim 9, characterized in that: At least two waveguides below the antenna are arranged in parallel.

13. A radio frequency device, characterized in that: include: A waveguide antenna as claimed in any one of claims 1 to 12.

14. A radar, characterized in that: include: The radio frequency device as claimed in claim 13.

Images