Waveguide device and related product

Abstract

A waveguide device and related products relate to the technical field of millimeter wave radars. The waveguide device comprises a first waveguide cavity, a first radiation port and a second radiation port, a signal in the first waveguide cavity is radiated through the first radiation port and the second radiation port; the distance between the radiation ends of the first radiation port and the second radiation port is smaller than the distance between the first radiation port and the connection end of the first waveguide cavity and the distance between the second radiation port and the connection end of the first waveguide cavity. According to the waveguide device, the series-fed waveguide with a simpler feed form is adopted, the complexity of a three-dimensional structure of the waveguide antenna can be reduced, the requirement for machining precision is lowered, the machining cost is lowered, and the advantages of the waveguide antenna in the aspect of radiation transmission efficiency can be guaranteed by lowering the side lobe level of the series-fed waveguide antenna.

Description

Waveguide devices and related products Technical Field

[0001] The present application relates to the field of millimeter wave radar technology, and in particular to a waveguide device and related products. Background Art

[0002] A waveguide is a structure used to guide electromagnetic waves in a certain direction. It is primarily used as a transmission line at microwave frequencies, connecting microwave transmitters and receivers to their antennas in microwave radio link equipment such as radar.

[0003] Compared to traditional printed circuit board (PCB) antennas, waveguide antennas offer significant advantages in radiation efficiency. Current radar implementations employ parallel-fed waveguide antennas, but these antennas have complex three-dimensional structures, require high machining precision, and incur high costs, making them less practical for engineering applications.

[0004] Summary of the Invention

[0005] The embodiments of the present application provide a waveguide device and related products, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0006] In a first aspect, an embodiment of the present application provides a waveguide device, the waveguide device comprising:

[0007] a first waveguide cavity, a first radiation port and a second radiation port;

[0008] The signal in the first waveguide cavity is radiated through the first radiation port and the second radiation port;

[0009] The distance between the radiation ends of the first radiation port and the second radiation port is smaller than the distance between the connection ends of the first radiation port and the second radiation port and the first waveguide cavity.

[0010] In an embodiment of the present application, the distance between the radiating end of the first radiation port and the radiating end of the second radiation port in the waveguide device is a first distance, and the distance between the connecting end of the first radiation port and the first waveguide cavity and the connecting end of the second radiation port and the first waveguide cavity is a second distance. By setting the first distance to be smaller than the second distance, the grating lobe of the waveguide antenna can be suppressed, thereby reducing the side lobe level of the waveguide antenna.

[0011] It can be understood that the distance between the first radiation port and the second radiation port in the embodiment of the present application gradually decreases in the direction in which the signal is radiated through the radiation port. The reduction in the distance between the radiation ports can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0012] The current parallel-fed waveguide antenna has a complex three-dimensional structure, high requirements for processing precision, and high processing costs. However, the embodiment of the present application can realize a series-fed waveguide antenna with low sidelobe level by setting the distance between the radiating ends of the two radiating ports to be smaller than the distance between the connecting ends of the two radiating ports and the waveguide cavity. Compared with the current parallel-fed waveguide antenna, the waveguide device in the embodiment of the present application adopts a series-fed waveguide with a simpler feeding form, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing precision, and reduce processing costs. In addition, by reducing the sidelobe level of the series-fed waveguide antenna, the advantages of the waveguide antenna in radiation transmission efficiency can be guaranteed.

[0013] In a possible implementation manner, the first radiation port includes a first sub-radiation segment and a second sub-radiation segment that are connected, and the second radiation port includes a third sub-radiation segment and a fourth sub-radiation segment that are connected;

[0014] The first sub-radiation segment and the third sub-radiation segment are radiation segments close to the first waveguide cavity, and the second sub-radiation segment and the fourth sub-radiation segment are radiation segments far from the first waveguide cavity;

[0015] The distance between the second sub-radiation section and the fourth sub-radiation section is smaller than the distance between the first sub-radiation section and the third sub-radiation section.

[0016] In an embodiment of the present application, a possible specific implementation of a first radiation port and a second radiation port is provided, specifically, the first radiation port includes a first sub-radiation segment and a second sub-radiation segment that are connected, and the second radiation port includes a third sub-radiation segment and a fourth sub-radiation segment that are connected, wherein the first sub-radiation segment and the third sub-radiation segment are radiation segments close to the first waveguide cavity, the second sub-radiation segment and the fourth sub-radiation segment are radiation segments away from the first waveguide cavity, and the spacing between the second sub-radiation segment and the fourth sub-radiation segment is smaller than the spacing between the first sub-radiation segment and the third sub-radiation segment.

[0017] It can be understood that the radiation port in the embodiment of the present application may include multiple (two or more) connected sub-radiation segments, and the multiple connected sub-radiation segments must meet the following conditions: the spacing between the sub-radiation segments of the two radiation ports away from the waveguide cavity is smaller than the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity.

[0018] Through the embodiments of the present application, the distance between the radiation ports is reduced in the direction of signal radiation, which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna, and realizing a series-fed waveguide antenna with a low side lobe level. It can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0019] In a possible implementation manner, the waveguide device further includes:

[0020] The third radiation port;

[0021] The first radiation port is located between the second radiation port and the third radiation port;

[0022] The signal in the first waveguide cavity is also radiated through the third radiation port;

[0023] The distance between the third radiation port and the radiation end of the first radiation port is less than or equal to the distance between the third radiation port and the connection end between the first radiation port and the first waveguide cavity; or

[0024] The distance between the third radiation port and the radiation end of the first radiation port is greater than the distance between the third radiation port and the connection end between the first radiation port and the first waveguide cavity.

[0025] In an embodiment of the present application, the waveguide device also includes a third radiation port, and the first radiation port is located between the second radiation port and the third radiation port. Compared with the third radiation port, the first radiation port and the second radiation port are distributed at a position closer to the center of the narrow side wall of the first waveguide cavity. The distance between the radiation end of the third radiation port and the radiation end of the first radiation port is a third distance, and the distance between the connection end of the third radiation port and the first waveguide cavity and the connection end of the first radiation port and the first waveguide cavity is a fourth distance. At this time, regardless of whether the third distance is less than, equal to, or greater than the fourth distance, the grating lobe of the waveguide antenna can be suppressed to a certain extent, thereby reducing the side lobe level of the waveguide antenna.

[0026] It can be understood that the distance between the third radiation port and the first radiation port in the embodiment of the present application, whether it gradually becomes smaller, remains unchanged, or increases in the direction of radiation of the signal through the radiation port, can to a certain extent suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0027] It can be understood that the effect of suppressing the waveguide antenna grating lobe corresponding to the third spacing being smaller than the fourth spacing is better than the effect of suppressing the waveguide antenna grating lobe corresponding to the third spacing being larger than the fourth spacing, thereby reducing the effect of the side lobe level of the waveguide antenna. That is, the effect of suppressing the waveguide antenna grating lobe that gradually becomes smaller in the direction in which the signal is radiated through the radiation port is better than the effect of suppressing the waveguide antenna grating lobe that gradually becomes larger in the direction in which the signal is radiated through the radiation port, thereby reducing the side lobe level of the waveguide antenna.

[0028] In a possible implementation manner, the third radiation port includes a fifth sub-radiation segment and a sixth sub-radiation segment that are connected;

[0029] The fifth sub-radiation segment is a radiation segment close to the first waveguide cavity, and the sixth sub-radiation segment is a radiation segment far from the first waveguide cavity;

[0030] The distance between the sixth sub-radiation section and the second sub-radiation section is less than or equal to the distance between the fifth sub-radiation section and the first sub-radiation section; or,

[0031] The distance between the sixth sub-radiation section and the second sub-radiation section is greater than the distance between the fifth sub-radiation section and the first sub-radiation section.

[0032] In an embodiment of the present application, a possible specific implementation of a third radiation port is provided, specifically, the third radiation port includes a connected fifth sub-radiation segment and a sixth sub-radiation segment, wherein the fifth sub-radiation segment is a radiation segment close to the first waveguide cavity, and the sixth sub-radiation segment is a radiation segment away from the first waveguide cavity, and the spacing between the sixth sub-radiation segment and the second sub-radiation segment can be less than or equal to or greater than the spacing between the fifth sub-radiation segment and the first sub-radiation segment, both of which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0033] It can be understood that the third radiation port and the first radiation port in the embodiment of the present application may include multiple (two or more) connected sub-radiation segments, and the multiple connected sub-radiation segments must meet the following conditions: the spacing between the sub-radiation segments of the third radiation port and the first radiation port away from the waveguide cavity can be less than or equal to the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity.

[0034] It can be understood that the effect of suppressing the waveguide antenna grating lobe corresponding to the spacing between the sub-radiation segments of the third radiation port and the first radiation port away from the waveguide cavity is smaller than the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity is better than the effect of suppressing the waveguide antenna grating lobe corresponding to the spacing between the sub-radiation segments of the third radiation port and the first radiation port away from the waveguide cavity is larger than the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity.

[0035] In a possible implementation manner, a distance between the second sub-radiation section and the fourth sub-radiation section is smaller than a distance between the second sub-radiation section and the sixth sub-radiation section.

[0036] In an embodiment of the present application, a possible specific implementation of the spacing relationship between the second sub-radiating segment, the fourth sub-radiating segment, and the sixth sub-radiating segment is provided, specifically, the spacing between the second sub-radiating segment and the fourth sub-radiating segment is smaller than the spacing between the second sub-radiating segment and the sixth sub-radiating segment. Because the first radiation port and the second radiation port are distributed on the narrow side wall of the first waveguide cavity, they are closer to the center of the narrow side wall of the first waveguide cavity than the location of the third radiation port on the narrow side wall of the first waveguide cavity. Therefore, in the embodiment of the present application, by setting the spacing between the second sub-radiating segment and the fourth sub-radiating segment to be smaller than the spacing between the second sub-radiating segment and the sixth sub-radiating segment, the grating lobe of the waveguide antenna can be suppressed, thereby reducing the sidelobe level of the waveguide antenna.

[0037] In a possible implementation manner, the interval s1 between the second sub-radiation segment and the fourth sub-radiation segment satisfies the following condition: 0.35λ0≤s1≤0.6λ0;

[0038] Here, λ0 represents the wavelength of electromagnetic waves in a vacuum.

[0039] In an embodiment of the present application, a possible specific implementation method of the spacing between the second sub-radiation segment and the fourth sub-radiation segment is provided. Specifically, the spacing s1 between the second sub-radiation segment and the fourth sub-radiation segment meets the above conditions, which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0040] In a possible implementation manner, the interval s2 between the first sub-radiation segment and the third sub-radiation segment satisfies the following condition: 0.4λ g ≤s2≤0.6λ g ;

[0041] Among them, the λ g Characterizes the wavelength of the electromagnetic wave transmitted in the first waveguide cavity.

[0042] In an embodiment of the present application, a possible specific implementation method of the spacing between the first sub-radiation segment and the third sub-radiation segment is provided. Specifically, the spacing s2 between the first sub-radiation segment and the third sub-radiation segment meets the above conditions, which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0043] In a possible implementation, the signal in the first waveguide cavity is radiated through the first radiation port and the second radiation port, including:

[0044] The signal in the first waveguide cavity is radiated from the first radiation port and the second radiation port along a first direction through the first surface of the first waveguide cavity;

[0045] The width of the first surface in the second direction is the same as the width of the radiation port, the length of the first surface in the third direction is the same as the length of the first waveguide cavity, and the first direction, the second direction and the third direction are perpendicular to each other.

[0046] In an embodiment of the present application, a possible specific embodiment of the positional relationship between the first waveguide cavity and the radiation port is provided, specifically, the first radiation port and the second radiation port are distributed at the position of the narrow side wall of the first waveguide cavity (i.e., the first surface of the first waveguide cavity), and the signal in the first waveguide cavity is radiated from the first radiation port and the second radiation port along the first direction through the first surface of the first waveguide cavity. In addition, the width of the first surface in the second direction is the same as the width of the radiation port, and the length of the first surface in the third direction is the same as the length of the first waveguide cavity. The first direction, the second direction, and the third direction are perpendicular to each other. It can be understood that the first direction, the second direction, and the third direction are mutually perpendicular to each other to form a three-dimensional space. Through the embodiment of the present application, the first radiation port and the second radiation port are distributed on the narrow side wall of the first waveguide cavity, and the signal in the first waveguide cavity is radiated from the first radiation port and the second radiation port along the first direction through the narrow side wall of the first waveguide cavity, which can improve the radiation efficiency of the signal.

[0047] In a possible implementation, the three-dimensional dimensions L1, a1, and b1 of the first waveguide cavity satisfy the following conditions: 0.85×(N×λ g / 2)≤L1≤1.15×(N×λ g / 2), 0 <a1≤0.5λ g , 0.5λ g ≤b1≤λ g ;

[0048] Among them, the λ g Characterizes the wavelength of the electromagnetic wave transmitted in the first waveguide cavity, where N is the number of radiation ports;

[0049] L1 is the length of the first waveguide cavity in the third direction, a1 is the width of the first waveguide cavity in the second direction, and b1 is the height of the first waveguide cavity in the first direction.

[0050] In an embodiment of the present application, a possible specific implementation of the three-dimensional dimensions of the first waveguide cavity is provided. Specifically, the length of the first waveguide cavity in the third direction is L1, the width of the first waveguide cavity in the second direction is a1, and the height of the first waveguide cavity in the first direction is b1. The three-dimensional dimensions L1, a1, and b1 of the first waveguide cavity meet the above conditions, which can achieve a steady-state field distribution in the first waveguide cavity and improve the transmission efficiency of the signal in the first waveguide cavity.

[0051] In a possible implementation manner, the distance d1 between the two first waveguide cavities in the waveguide device satisfies the following condition: 0.5λ0≤d1≤1.5λ0;

[0052] Here, λ0 represents the wavelength of electromagnetic waves in a vacuum.

[0053] In an embodiment of the present application, a possible specific implementation of the spacing between two first waveguide cavities in a waveguide device is provided. Specifically, the spacing d1 between two (or more) first waveguide cavities in the waveguide device satisfies the above conditions, which can simplify the feeding network, realize the small-pitch array of the waveguide antenna array, reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0054] In a possible implementation, the first waveguide cavity has a bending structure, and the bending structure is used to connect the first radiation port and the second radiation port.

[0055] In an embodiment of the present application, a possible specific embodiment of a first waveguide cavity is provided, specifically, the first waveguide cavity includes a bending structure, the bending structure is used to connect the first radiation port and the second radiation port, wherein the bending structure can be a straight bend or a curved bend (for example, including but not limited to a triangular waveform, a sine waveform, a cosine waveform, etc.), and the embodiment of the present application does not limit this. Through the embodiment of the present application, after the straight waveguide is transformed into a waveguide with a bending structure and the radiation port is designed on the narrow side wall, the spatial distance of the radiation port can be reduced within an entire waveguide wavelength, the grating lobe of the waveguide antenna is suppressed, thereby reducing the side lobe level of the waveguide antenna, and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0056] In a possible implementation, the cross-sectional dimensions x1 and y1 of the bending structure in the first direction satisfy the following conditions: 0.15λ g ≤x1≤0.35λ g , 0.65λ g ≤y1≤0.85λ g ;

[0057] Wherein, x1 is the length of the bending structure in the second direction, and y1 is the length of the bending structure in the third direction.

[0058] In an embodiment of the present application, a possible specific implementation of a bending structure is provided, specifically, the length of the bending structure in the second direction is x1, the length of the bending structure in the third direction is y1, and the cross-sectional dimensions x1 and y1 of the bending structure in the first direction meet the above conditions, which can achieve the reduction of the spatial distance of the radiation port within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna, and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0059] In a possible implementation, a sidelobe level of a directivity pattern corresponding to the waveguide device is less than a first threshold.

[0060] In an embodiment of the present application, by setting the spacing between the radiating ends of the two radiating ports to be smaller than the spacing between the connecting ends of the two radiating ports and the waveguide cavity, a series-fed waveguide antenna with a low sidelobe level can be realized, so that the sidelobe level of the radiation pattern corresponding to the waveguide device is smaller than the first threshold, thereby improving the anti-interference capability of the waveguide antenna. The use of a series-fed waveguide with a simpler feeding form can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs. By reducing the sidelobe level of the series-fed waveguide antenna, the advantages of the waveguide antenna in radiation transmission efficiency can be guaranteed.

[0061] It is understood that the first threshold value in the embodiments of the present application is not a fixed value and can be adjusted according to different application scenarios. For example, the waveguide device in the embodiments of the present application has a significant advantage in radiation efficiency compared to traditional PCB printed antennas. In this case, by adjusting the first threshold value, the sidelobe level of the radiation pattern corresponding to the waveguide device can be reduced to the sidelobe level of the radiation pattern corresponding to the traditional PCB printed antenna.

[0062] In a second aspect, an embodiment of the present application provides a waveguide device, the waveguide device comprising:

[0063] a second waveguide cavity, M radiation ports, where M is an integer greater than 1;

[0064] The signal in the second waveguide cavity is radiated through the M radiation ports;

[0065] The second waveguide cavity has a bending structure, and the bending structure is used to connect the M radiation ports.

[0066] In the embodiment of the present application, the second waveguide cavity in the waveguide device has a zigzag structure that connects M radiation ports, through which signals in the second waveguide cavity are radiated. The zigzag structure can be a straight or curved bend (e.g., including but not limited to a triangular waveform, a sine waveform, a cosine waveform, etc.), which is not limited in the embodiment of the present application.

[0067] It can be understood that the bending structure used to connect M radiation ports in the embodiment of the present application can reduce the spatial distance between the radiation ports within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, and thus reduce the side lobe level of the waveguide antenna.

[0068] The current parallel-fed waveguide antenna has a complex three-dimensional structure, high requirements for processing precision, and high processing costs. However, the embodiment of the present application, by transforming a straight waveguide into a waveguide with a bent structure and then designing a radiation port on the narrow side wall, can reduce the spatial distance of the radiation port within a whole waveguide wavelength, suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna, and ensuring the advantage of the waveguide antenna in radiation transmission efficiency, thereby realizing a series-fed waveguide antenna with a low side lobe level. Compared with the current parallel-fed waveguide antenna, the waveguide device in the embodiment of the present application adopts a series-fed waveguide with a simpler feeding form, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing precision, and reduce processing costs. In addition, by reducing the side lobe level of the series-fed waveguide antenna, the advantage of the waveguide antenna in radiation transmission efficiency can be ensured.

[0069] In a possible implementation manner, radiating the signal in the second waveguide cavity through the M radiation ports includes:

[0070] The signal in the second waveguide cavity is radiated from the M radiation ports along the first direction through the first surface of the second waveguide cavity;

[0071] The width of the first surface in the second direction is the same as the width of the radiation port, the length of the first surface in the third direction is the same as the length of the second waveguide cavity, and the first direction, the second direction and the third direction are perpendicular to each other.

[0072] In an embodiment of the present application, a possible specific embodiment of the positional relationship between the second waveguide cavity and the radiation port is provided. Specifically, M radiation ports are distributed on the narrow sidewall of the second waveguide cavity (i.e., the first surface of the second waveguide cavity). At this time, the signal in the second waveguide cavity is radiated from the M radiation ports along the first direction through the first surface of the second waveguide cavity. In addition, the width of the first surface in the second direction is the same as the width of the radiation port, and the length of the first surface in the third direction is the same as the length of the first waveguide cavity. The first direction, the second direction, and the third direction are mutually perpendicular. It can be understood that the first direction, the second direction, and the third direction are mutually perpendicular to each other to form a three-dimensional space. Through the embodiment of the present application, the M radiation ports are distributed on the narrow sidewall of the second waveguide cavity, and the signal in the second waveguide cavity is radiated from the M radiation ports along the first direction through the narrow sidewall of the second waveguide cavity, which can improve the radiation efficiency of the signal.

[0073] In a possible implementation, the cross-sectional dimensions x2 and y2 of the bending structure in the first direction satisfy the following conditions: 0.15λ g ≤x2≤0.35λ g , 0.65λ g ≤y2≤0.85λ g ;

[0074] Wherein, x2 is the length of the bending structure in the second direction, and y2 is the length of the bending structure in the third direction.

[0075] In an embodiment of the present application, a possible specific implementation of a bending structure is provided, specifically, the length of the bending structure in the second direction is x2, the length of the bending structure in the third direction is y2, and the cross-sectional dimensions x2 and y2 of the bending structure in the first direction meet the above conditions, which can achieve the reduction of the spatial distance of the radiation port within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna, and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0076] In a possible implementation, the three-dimensional dimensions L2, a2, and b2 of the second waveguide cavity satisfy the following conditions: 0.85×(M×λ g / 2)≤L2≤1.15×(M×λ g / 2), 0 <a2≤0.5λ g , 0.5λ g ≤b2≤λ g ;

[0077] Among them, the λ g Characterizing the wavelength of the electromagnetic wave transmitted in the second waveguide cavity;

[0078] L2 is the length of the second waveguide cavity in the third direction, a2 is the width of the second waveguide cavity in the second direction, and b2 is the height of the second waveguide cavity in the first direction.

[0079] In an embodiment of the present application, a possible specific implementation of the three-dimensional dimensions of the second waveguide cavity is provided. Specifically, the length of the second waveguide cavity in the third direction is L2, the width of the second waveguide cavity in the second direction is a2, and the height of the second waveguide cavity in the first direction is b2. The three-dimensional dimensions L2, a2, and b2 of the second waveguide cavity meet the above conditions, which can achieve a steady-state field distribution in the second waveguide cavity and improve the transmission efficiency of the signal in the second waveguide cavity.

[0080] In a possible implementation manner, the distance d2 between the two second waveguide cavities in the waveguide device satisfies the following condition: 0.5λ0≤d2≤1.5λ0;

[0081] Here, λ0 represents the wavelength of electromagnetic waves in a vacuum.

[0082] In an embodiment of the present application, a possible specific implementation of the spacing between two second waveguide cavities in a waveguide device is provided. Specifically, the spacing d2 between two (or more) second waveguide cavities in the waveguide device satisfies the above conditions, which can simplify the feeding network, realize the small-pitch array of the waveguide antenna array, reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0083] In a possible implementation manner, the spacing s3 between two adjacent radiation ports among the M radiation ports satisfies the following condition: 0.35λ0≤s3≤0.6λ0;

[0084] Here, λ0 represents the wavelength of electromagnetic waves in a vacuum.

[0085] In an embodiment of the present application, a possible specific implementation of the spacing between two adjacent radiation ports among M radiation ports is provided. Specifically, the spacing s3 between two adjacent radiation ports among M radiation ports meets the above conditions, which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0086] In a possible implementation manner, a sidelobe level of the directivity pattern corresponding to the waveguide device is less than a second threshold.

[0087] In the embodiment of the present application, a series-fed waveguide antenna with low sidelobe level can be realized by transforming a straight waveguide into a waveguide with a bending structure and then designing a radiation port on the narrow side wall, so that the sidelobe level of the radiation pattern corresponding to the waveguide device is less than the second threshold value, thereby improving the anti-interference ability of the waveguide antenna. The use of a series-fed waveguide with a simpler feeding form can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs. By reducing the sidelobe level of the series-fed waveguide antenna, the advantages of the waveguide antenna in radiation transmission efficiency can be guaranteed.

[0088] It is understood that the second threshold value in the embodiments of the present application is not a fixed value and can be adjusted according to different application scenarios. For example, the waveguide device in the embodiments of the present application has a significant advantage in radiation efficiency compared to traditional PCB printed antennas. In this case, by adjusting the second threshold value, the sidelobe level of the radiation pattern corresponding to the waveguide device can be reduced to the sidelobe level of the radiation pattern corresponding to the traditional PCB printed antenna.

[0089] In a third aspect, embodiments of the present application provide a radar or radar system, comprising the waveguide device described in the first aspect or any possible embodiment of the first aspect, or the waveguide device described in the second aspect or any possible embodiment of the second aspect. It should be noted that there may be smart sensors that integrate multiple sensors. If the smart sensor includes millimeter-wave detection capabilities, the smart sensor may also be referred to as a millimeter-wave radar or millimeter-wave radar system.

[0090] In a fourth aspect, an embodiment of the present application provides a terminal device, which includes the waveguide device described in the first aspect or any possible embodiment of the first aspect, or includes the waveguide device described in the second aspect or any possible embodiment of the second aspect, or includes the radar or radar system described in the third aspect.

[0091] In the fifth aspect, an embodiment of the present application provides a vehicle end, which includes the waveguide device described in the first aspect or any possible embodiment of the first aspect, or includes the waveguide device described in the second aspect or any possible embodiment of the second aspect, or includes the radar or radar system described in the third aspect, or includes the terminal equipment described in the fourth aspect.

[0092] In the embodiment of the present application, a series-fed waveguide with a simpler feeding form is used, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs. In addition, by reducing the sidelobe level of the series-fed waveguide antenna, the advantages of the waveguide antenna in radiation transmission efficiency can be guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0094] FIG1 is a schematic diagram of a radar distribution according to an embodiment of the present application;

[0095] FIG2 is a schematic diagram of the architecture of a radar provided in an embodiment of the present application;

[0096] FIG3 is a schematic structural diagram of a waveguide antenna feeding network provided in an embodiment of the present application;

[0097] FIG4 is a schematic structural diagram of a waveguide antenna feeding network provided in an embodiment of the present application;

[0098] FIG5 is a schematic structural diagram of a waveguide device provided in an embodiment of the present application;

[0099] FIG6 is a plan view of a waveguide device provided in an embodiment of the present application;

[0100] FIG7 is a plan view of a waveguide device provided in an embodiment of the present application;

[0101] FIG8A is a plan view of a waveguide device provided in an embodiment of the present application;

[0102] FIG8B is a plan view of a waveguide device provided in an embodiment of the present application;

[0103] FIG8C is a plan view of a waveguide device provided in an embodiment of the present application;

[0104] FIG8D is a plan view of a waveguide device provided in an embodiment of the present application;

[0105] FIG9A is a plan view of a waveguide device provided in an embodiment of the present application;

[0106] FIG9B is a plan view of a waveguide device provided in an embodiment of the present application;

[0107] FIG10A is a schematic diagram of signal distribution of a waveguide device provided in an embodiment of the present application;

[0108] FIG10B is a schematic diagram showing the effect of a radiation pattern provided by an embodiment of the present application;

[0109] FIG11A is a schematic diagram of signal distribution of a waveguide device provided in an embodiment of the present application;

[0110] FIG11B is a schematic diagram showing the effect of a radiation pattern provided by an embodiment of the present application;

[0111] FIG12 is a schematic structural diagram of another waveguide device provided in an embodiment of the present application;

[0112] FIG13 is a plan view of a waveguide device provided in an embodiment of the present application;

[0113] FIG14A is a plan view of a waveguide device provided in an embodiment of the present application;

[0114] FIG14B is a plan view of a waveguide device provided in an embodiment of the present application;

[0115] FIG14C is a plan view of a waveguide device provided in an embodiment of the present application;

[0116] FIG14D is a plan view of a waveguide device provided in an embodiment of the present application;

[0117] FIG15A is a schematic diagram of signal distribution of a waveguide device provided in an embodiment of the present application;

[0118] FIG15B is a schematic diagram showing the effect of a radiation pattern provided by an embodiment of the present application;

[0119] FIG16 is a schematic diagram of a waveguide antenna feeding network provided in an embodiment of the present application;

[0120] FIG17A is a schematic diagram of a return loss effect provided by an embodiment of the present application;

[0121] FIG17B is a schematic diagram of the effect of transmission isolation provided in an embodiment of the present application. DETAILED DESCRIPTION

[0122] In order to make the purpose, technical solutions and advantages of this application clearer, the embodiments of this application will be described below in conjunction with the drawings in the embodiments of this application.

[0123] The terms "first" and "second" in the specification, claims, and drawings of this application are used to distinguish different objects, not to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to the process, method, product, or device.

[0124] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It will be understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0125] It should be understood that in the present application, "at least one (item)" refers to one or more, "more than one" refers to two or more, "at least two (items)" refers to two or three and more than three, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0126] As described in the background technology section, research is currently needed to address the complex three-dimensional structure and high processing costs of waveguide antennas. This application provides a waveguide device and related products related to the field of millimeter-wave radar technology. This device utilizes a simpler feeding method, such as a series-fed waveguide, to reduce the complexity of the waveguide antenna's three-dimensional structure, lower the requirements for processing accuracy, and reduce processing costs. Furthermore, by reducing the sidelobe level of the series-fed waveguide antenna, the waveguide antenna's advantages in radiation transmission efficiency can be maintained.

[0127] In order to more clearly describe the solution of this application, some knowledge related to radar is first introduced below.

[0128] The signal processing system provided in the embodiment of the present application is described below in conjunction with the drawings in the embodiment of the present application.

[0129] Radar is the transliteration of the English word Radar, which comes from the abbreviation of "radio detection and ranging", meaning "radio detection and ranging". It uses radio methods to detect targets and determine the spatial position of targets.

[0130] Radar uses electromagnetic waves as its detection medium, and it uses the transmission and reception of electromagnetic waves to detect targets, for example, to measure distance, speed, or azimuth. Radar can measure distance to a target based on the time of flight of electromagnetic waves, which is the time difference between the transmission and reception of electromagnetic waves. Radar transmits an electromagnetic wave signal and receives an echo signal. The distance to the target is determined based on the time difference between the received echo signal and the transmitted electromagnetic wave signal and the propagation speed of the electromagnetic wave. The distance between the radar and the target can be determined using the following formula: s = c * t / 2, where s is the distance to the target, t is the time of flight (the time from the radar transmitting the electromagnetic wave signal to the receipt of the echo signal), and c is the speed of light.

[0131] Radar uses the Doppler effect to measure target velocity. The Doppler effect works as follows: when a vibration source, such as sound, light, or radio waves, moves relative to an observer at a relative speed, the frequency of the vibration received by the observer differs from the frequency emitted by the source. When the electromagnetic waves emitted by the radar and the target are in relative motion, the frequency of the echo signal will differ from the frequency of the transmitted electromagnetic wave. When the target approaches the radar antenna, the frequency of the echo signal will be higher than the frequency of the transmitted electromagnetic wave; conversely, when the target moves away from the radar antenna, the frequency of the echo signal will be lower than the frequency of the transmitted electromagnetic wave. The frequency change caused by the Doppler effect is called the Doppler shift, which is proportional to the relative velocity and inversely proportional to the vibration frequency. Therefore, by detecting the frequency difference between the transmitted electromagnetic wave signal and the echo signal, the target's speed relative to the radar—that is, the relative speed between the target and the radar—can be measured.

[0132] Radar can use amplitude method, phase method and other methods to measure azimuth angle. The amplitude method uses the amplitude value of the echo signal received by the antenna to measure the angle. The change pattern of the amplitude value depends on the antenna radiation pattern and the antenna scanning method; the phase method uses the phase difference between the echo signals received by multiple antenna units to measure the angle. For example, the radar receives the echo signal reflected by the same target through the antenna array, and calculates the azimuth angle of the target based on the phase difference of the echo signal.

[0133] Millimeter-wave radar uses electromagnetic waves within a certain wavelength range, such as microwaves. Currently, millimeter waves and adjacent centimeter waves (e.g., centimeter waves in the 24 GHz band) are more commonly used. Millimeter waves have wavelengths of 1 to 10 millimeters (mm), with those in the 24 GHz band having wavelengths slightly larger than 10 mm. Because the wavelength of millimeter-wave radar's detection medium lies in the overlapping wavelength range of microwaves and far-infrared waves, it combines the characteristics of both spectrums. According to wave propagation theory, higher frequencies and shorter wavelengths yield higher resolution and greater penetration, but also greater propagation losses and shorter transmission distances. Conversely, lower frequencies and longer wavelengths yield greater diffraction resistance and longer transmission distances. Therefore, compared to microwaves, millimeter-wave radar's detection medium offers higher resolution, better directivity, stronger anti-interference capabilities, and superior detection performance. Compared to infrared, millimeter-wave radar experiences less atmospheric attenuation, has better penetration of smoke and dust, and is less affected by weather. Therefore, millimeter-wave radar has been increasingly widely used in many fields such as smart vehicles, drones, smart transportation, and industrial automation.

[0134] Radar can be categorized by detection range into long-range radar (LRR), mid-range radar (MRR), and short-range radar (SRR). LRR has higher detection range requirements but lower angular detection width requirements. SRR has lower detection range requirements but higher angular detection width requirements. MRR's detection range and angular detection width requirements can be understood as falling between those of LRR and SRR. For example, LRR's detection range can exceed 200 meters and its angular detection width can be ±15°; MRR's detection range is within 100 meters and its angular detection width can be ±45°; and SRR's detection range is within 60 meters and its angular detection width can be ±80°. Different types of radar can be installed in different locations on the vehicle body, depending on the autonomous driving functional requirements and the use of other sensors. The number and type of radars can be selected as needed.

[0135] Please refer to FIG1 , which is a schematic diagram of a radar distribution provided in an embodiment of the present application.

[0136] FIG1 shows possible installation locations of several types of radars. This is only an example. In actual use, a greater or lesser number of radars may be selected, and the types may also be adjusted.

[0137] As shown in Figure 1, the LRR can be installed in front of the vehicle as a forward-facing radar; the MRR can be installed in front of or behind the vehicle as a forward-facing radar and a rear-facing radar; and the SRR can be installed on the side or at the four corners of the vehicle as a side-facing radar and a corner radar. Furthermore, the MRR can also be installed on the side or at the four corners of the vehicle, and the SRR can also be installed in the front or rear of the vehicle.

[0138] Radars can be classified based on the modulation method (or radiation method) of their electromagnetic waves. Radar electromagnetic wave modulation methods include pulse and continuous wave, so radars can be divided into pulse radars and continuous wave radars. Continuous wave methods can be further divided into frequency shift keying (FSK), phase shift keying (PSK), constant frequency / single frequency continuous wave (CW), frequency modulated continuous wave (FMCW), multiple frequency shift keying (MFSK), and phase modulated continuous wave (PMCW). FMCW has become the mainstream radar modulation method due to its ability to detect multiple targets, high resolution, and low cost.

[0139] Please refer to FIG2 , which is a schematic diagram of the architecture of a radar provided in an embodiment of the present application.

[0140] As shown in Figure 2, the radar includes an MMIC, a microcontroller unit (MCU), and a power management integrated circuit (PMIC). The MMIC can integrate the functions of the radio frequency part, and the MCU can integrate the functions of the baseband part, such as the function of the integrated signal processor. In addition, it can also provide a communication interface with other on-board devices. The PMIC is the chip that powers the radar hardware system.

[0141] A waveguide is a structure used to guide electromagnetic waves in a certain direction. In electromagnetics and communications engineering, a waveguide refers to any linear structure that transmits electromagnetic waves between its endpoints. Waveguides are primarily used as transmission lines at microwave frequencies, connecting microwave transmitters and receivers to their antennas in radar, communications satellites, and microwave radio link equipment.

[0142] Currently, millimeter-wave automotive radar antennas are being developed to meet the evolving needs of system functionality, requiring them to achieve higher efficiency and wider bandwidth. Compared to traditional printed circuit board (PCB) antennas, waveguide antennas offer significant advantages in radiation transmission efficiency and broadband performance. However, the complex three-dimensional structure of waveguide antenna feed networks limits their application in millimeter-wave radar due to size and manufacturing costs. Therefore, significantly simplifying the waveguide antenna structure while maintaining performance could greatly enhance its application in millimeter-wave radar.

[0143] Please refer to FIG3 , which is a schematic structural diagram of a waveguide antenna feeding network provided in an embodiment of the present application.

[0144] As shown in Figure 3, a waveguide antenna feeding network is implemented using a multi-stage T-type power divider. Specifically, a multi-stage parallel two-stage HT power divider is used to achieve a one-to-eight power splitting feeding. In the final power divider, an offset feed design is used to achieve amplitude and phase weighting of the radiating port, thereby reducing the sidelobe level of the V-plane radiation pattern.

[0145] The processing technology for preparing the waveguide antenna feed network is to achieve processing through a four-layer cutting method. After cutting, each layer of structural parts is formed by plastic mold processing, and then the surface is metallized through a surface electroplating process. Finally, the structure of the waveguide antenna feed network is obtained through an interlayer brazing process.

[0146] As can be seen from Figure 3, the three-dimensional structure of the waveguide antenna feed network is complex, requiring high machining precision and resulting in high machining costs. Furthermore, the present embodiment uses only eight radiating ports as an example. As the number of radiating ports increases, the waveguide antenna feed network requires more stages of T-type power splitters, resulting in a higher cross-sectional height of the waveguide antenna feed network. This results in a complex three-dimensional structure, high machining precision requirements for multi-layer processing, poor tolerance tolerance, high machining costs, and low practical engineering value.

[0147] Please refer to FIG4 , which is a schematic structural diagram of a waveguide antenna feeding network provided in an embodiment of the present application.

[0148] As shown in FIG4 , a waveguide antenna feeding network is implemented using a series-fed waveguide antenna with a simpler feeding form. Compared with the parallel-fed waveguide antenna shown in FIG3 , the series-fed waveguide antenna in the embodiment of the present application can greatly simplify the complexity of the three-dimensional structure of the waveguide antenna feeding network, reduce the requirements for processing accuracy, and reduce processing costs.

[0149] However, given that the sidelobe level of the series-fed waveguide antenna with a simpler feeding form is higher, its signal radiation transmission efficiency is lower and its value in practical engineering applications is also lower.

[0150] In response to the problems that the three-dimensional structure of the above-mentioned waveguide antenna feeding network is complex, resulting in high processing costs, and the high sidelobe level leads to low radiation transmission efficiency of its signal, the embodiment of the present application designs a radar waveguide antenna feeding network that can operate in the millimeter wave frequency band of 76 to 78 GHz, so that it can not only ensure the advantages of the waveguide antenna in radiation transmission efficiency, but also solve the problems of complex three-dimensional structure and high processing cost of the current parallel-fed waveguide antenna.

[0151] The waveguide device provided in the embodiment of the present application is described below in conjunction with the drawings in the embodiment of the present application.

[0152] Please refer to FIG5 , which is a schematic structural diagram of a waveguide device provided in an embodiment of the present application.

[0153] As shown in FIG5 , the waveguide device includes:

[0154] A first waveguide cavity, a first radiation port P1 and a second radiation port P2;

[0155] The signal in the first waveguide cavity is radiated through the first radiation port P1 and the second radiation port P2;

[0156] The distance between the radiation ends of the first radiation port P1 and the second radiation port P2 is smaller than the distance between the connection ends of the first radiation port P1 and the second radiation port P2 and the first waveguide cavity.

[0157] It should be understood that the waveguide device shown in FIG5 includes four radiation ports, which is merely an exemplary embodiment. The waveguide device may also include more or fewer radiation ports, and this embodiment of the present application is not limited thereto. For greater simplicity and convenience, this embodiment of the present application uses the first radiation port P1 and the second radiation port P2 as an example for explanation, and this should not constitute a limitation on this embodiment of the present application.

[0158] Among them, the distance between the radiating end of the first radiation port P1 and the radiating end of the second radiation port P2 in the waveguide device is a first distance, and the distance between the connection end of the first radiation port P1 and the first waveguide cavity and the connection end of the second radiation port P2 and the first waveguide cavity is a second distance. By setting the first distance to be smaller than the second distance, the grating lobe of the waveguide antenna can be suppressed, thereby reducing the side lobe level of the waveguide antenna.

[0159] It can be understood that the above-mentioned radiation end and connection end refer to different parts into which the radiation port is divided according to the relative distance relationship with the first waveguide cavity. Specifically, the radiation end may refer to the end of the radiation port relatively far away from the first waveguide cavity, and the connection end may refer to the end of the radiation port relatively close to the first waveguide cavity. Exemplarily, for the first radiation port P1 in Figure 5, the end of the radiation port relatively far away from the first waveguide cavity is port P11, that is, the radiation end of the first radiation port P1 is port P11, and the end of the radiation port relatively far away from the first waveguide cavity is port P12, that is, the connection end of the first radiation port P1 is port P12. Exemplarily, for the second radiation port P2 in Figure 5, the end of the radiation port relatively far away from the first waveguide cavity is port P21, that is, the radiation end of the second radiation port P2 is port P21, and the end of the radiation port relatively far away from the first waveguide cavity is port P22, that is, the connection end of the second radiation port P2 is port P22. In an actual product structure, since the radiation port and the first waveguide cavity can be integrally formed, the connection end refers to the connection between the radiation portion and the first waveguide cavity.

[0160] It can be understood that the distance between the first radiation port and the second radiation port in the embodiment of the present application gradually decreases in the direction in which the signal is radiated through the radiation port, that is, the first direction (z direction) in Figure 5. The reduction in the distance between the radiation ports can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0161] It can be understood that the first direction (z-direction), the second direction (x-direction), and the third direction (y-direction) in Figure 5 are mutually perpendicular to each other, forming a three-dimensional space. In this case, the first direction (z-direction) is the direction in which the signal is radiated through the radiation port, the second direction (x-direction) is perpendicular to the wide sidewall of the first waveguide cavity, and the third direction (y-direction) is parallel to the wide sidewall of the first waveguide cavity.

[0162] Optionally, the waveguide device may further include an input waveguide for inputting a signal into the first waveguide cavity. Optionally, the input waveguide may also be another form of feeding structure for feeding a signal into the first waveguide cavity, which is not limited in this embodiment of the present application.

[0163] Current parallel-fed waveguide antennas (as shown in Figure 3 above) have complex three-dimensional structures, require high machining precision, and incur high costs. However, by setting the spacing between the radiating ends of the two radiating ports to be smaller than the spacing between the two ports and the connection ends of the waveguide cavity, the present embodiment achieves a series-fed waveguide antenna with low sidelobe levels.

[0164] Compared with the current parallel-fed waveguide antenna, the waveguide device in the embodiment of the present application adopts a series-fed waveguide with a simpler feeding form, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs. In addition, by setting the distance between the radiating ends of the two radiating ports to be smaller than the distance between the connecting ends of the two radiating ports and the waveguide cavity, the sidelobe level of the series-fed waveguide antenna can be reduced, which can ensure the advantages of the waveguide antenna in radiation transmission efficiency.

[0165] Optionally, the effect of achieving low sidelobe levels for a series-fed waveguide antenna by reducing the spatial distance between radiating ports can be explained by combining the antenna array element spacing and sidelobe level principles, as follows:

[0166] Arrange N radiation sources in a straight line along the Z axis. Assume that each unit has the same amplitude and the previous unit leads the next unit by a phase value of β (an array in which the amplitude and phase of each unit are equal is called a uniform array).

[0167] According to the antenna array pattern product theorem (total pattern = element factor × array factor), when all elements in the array are identical, the elements can be treated as point sources to calculate the array factor. From the first element onward, the phase of each element arriving at the observation point lags behind the phase by kd cosθ + β, resulting in an array factor of:

[0168] Among them, the above formula is a geometric sequence. According to the summation formula of geometric sequence, we can get:

[0169] Assuming the center of the array is the origin, the above formula can be simplified to:

[0170] When ψ approaches 0, we can use L'Hôpital's rule to find the limit of the above formula and get:

[0171] That is, the maximum value of AF is approximately N, and the normalized array factor is:

[0172] When ψ is small, or N is large enough, the above formula can be simplified to:

[0173] According to ψ=kd cosθ+β, different values ​​of kd and β can realize different types of array patterns:

[0174] (1) Side-firing array: The maximum radiation direction is perpendicular to the array axis (the axis of the array arrangement), θ m =90deg;

[0175] (2) End-fire array: The maximum radiation direction is perpendicular to the array axis, θ m=0 / 180deg;

[0176] (3) Phased array: The maximum radiation direction changes with time.

[0177] The one-dimensional antenna array in the embodiment of the present application is a broadside array, and the array factor expression shows that the main lobe of the array always appears at kd cosθ+β=0;

[0178] For a side-shooting array, θ m =90deg, we can get:

[0179] β=-kd cosθ m =0

[0180] From the above formula, we can see that the phase difference of each array element is 0, that is, an equal amplitude and in-phase array. The array spacing d can be any distance that is not an integer multiple of the wavelength. Because when d = nλ, ψ = kd cosθ = ±2nπcosθ. This makes AF n When θ = 0° or 180°, there is also a maximum value, namely the grating lobe (the grating lobe is one of the side lobes). These grating lobe channels should be avoided, so it is usually necessary to make the maximum spacing d max Less than a wavelength.

[0181] Therefore, by reducing the spatial distance between the radiation ports, the sidelobe level of the series-fed waveguide antenna can be reduced.

[0182] Please refer to Figure 6, which is a plan view of a waveguide device provided in an embodiment of the present application. It is understood that the waveguide device shown in Figure 6 can be implemented as a separate embodiment; alternatively, the waveguide device shown in Figure 6 can be understood as a variation or supplement to the waveguide device shown in Figure 5. In this case, Figure 6 can be understood as a plan view of the waveguide device shown in Figure 5 in the second direction (x direction).

[0183] As shown in FIG6 , the waveguide device includes:

[0184] A first waveguide cavity, a first radiation port P1 and a second radiation port P2;

[0185] The signal in the first waveguide cavity is radiated through the first radiation port P1 and the second radiation port P2;

[0186] The distance between the radiation ends of the first radiation port P1 and the second radiation port P2 is smaller than the distance between the connection ends of the first radiation port P1 and the second radiation port P2 and the first waveguide cavity.

[0187] It should be understood that the waveguide device shown in FIG5 includes four radiation ports, which is merely an exemplary embodiment. The waveguide device may also include more or fewer radiation ports, and this embodiment of the present application is not limited thereto. For greater simplicity and convenience, this embodiment of the present application uses the first radiation port P1 and the second radiation port P2 as an example for explanation, and this should not constitute a limitation on this embodiment of the present application.

[0188] The first radiation port P1 includes a first sub-radiation segment q1 and a second sub-radiation segment q2 that are connected, and the second radiation port P2 includes a third sub-radiation segment q3 and a fourth sub-radiation segment q4 that are connected;

[0189] The first sub-radiation segment q1 and the third sub-radiation segment q3 are radiation segments close to the first waveguide cavity, and the second sub-radiation segment q2 and the fourth sub-radiation segment q4 are radiation segments far away from the first waveguide cavity;

[0190] The distance between the second sub-radiation section q2 and the fourth sub-radiation section q4 is smaller than the distance between the first sub-radiation section q1 and the third sub-radiation section q3.

[0191] The aforementioned sub-radiation segments refer to different sections of the radiation port divided based on their relative proximity to the first waveguide cavity. Specifically, the first sub-radiation segment q1 and the third sub-radiation segment q3 may refer to radiation segments close to the first waveguide cavity, while the second sub-radiation segment q2 and the fourth sub-radiation segment q4 may refer to radiation segments farther from the first waveguide cavity. Furthermore, the spacing between the second sub-radiation segment q2 and the fourth sub-radiation segment q4 (i.e., spacing s1) is smaller than the spacing between the first sub-radiation segment q1 and the third sub-radiation segment q3 (i.e., spacing s2).

[0192] It can be understood that the radiation port in the embodiment of the present application may include multiple (two or more) connected sub-radiation segments, and the multiple connected sub-radiation segments must meet the following conditions: the spacing between the sub-radiation segments of the two radiation ports away from the waveguide cavity is smaller than the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity.

[0193] It can be understood that the spacing between the sub-radiating segments of the two radiation ports in the embodiment of the present application gradually decreases in the direction in which the signal is radiated through the radiation port, that is, the first direction (z direction). The reduction in the spacing between the radiation ports can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0194] It can be understood that the first direction (z-direction) and the third direction (y-direction) in Figure 6 are perpendicular to each other, and the plane formed by the first direction (z-direction) and the third direction (y-direction) is perpendicular to the second direction (x-direction). In this case, the first direction (z-direction) is the direction in which the signal is radiated through the radiation port, the second direction (x-direction) is perpendicular to the wide sidewall of the first waveguide cavity, and the third direction (y-direction) is parallel to the wide sidewall of the first waveguide cavity.

[0195] Optionally, the waveguide device may further include an input waveguide for inputting a signal into the first waveguide cavity. Optionally, the input waveguide may also be another form of feeding structure for feeding a signal into the first waveguide cavity, which is not limited in this embodiment of the present application.

[0196] Through the embodiments of the present application, the distance between the radiation ports is reduced in the direction of signal radiation, which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna, and realizing a series-fed waveguide antenna with a low side lobe level. It can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0197] In a possible embodiment, the waveguide device shown in FIG. 5 or FIG. 6 further includes a third radiation port.

[0198] For details, please refer to Figure 7, which is a plan view of a waveguide device provided in an embodiment of the present application. It is understood that the waveguide device shown in Figure 7 can be implemented as a separate embodiment; alternatively, the waveguide device shown in Figure 7 can be understood as a variation or supplement to the waveguide device shown in Figures 5 or 6 above. In this case, Figure 7 can be understood as a plan view of the waveguide device shown in Figure 5 above in the second direction (x direction).

[0199] As shown in FIG7 , the waveguide device further includes:

[0200] The third radiation port P3;

[0201] The first radiation port P1 is located between the second radiation port P2 and the third radiation port P3;

[0202] The signal in the first waveguide cavity is also radiated through the third radiation port P3;

[0203] The distance between the third radiation port P3 and the radiation end of the first radiation port P1 is less than or equal to the distance between the third radiation port P3 and the connection end of the first radiation port P1 and the first waveguide cavity; or,

[0204] The distance between the third radiation port P3 and the radiation end of the first radiation port P1 is greater than the distance between the third radiation port P3 and the connection end of the first radiation port P1 and the first waveguide cavity.

[0205] It should be understood that the waveguide device shown in FIG7 includes four radiation ports, which is merely an exemplary embodiment. The waveguide device may also include more or fewer radiation ports, and the present embodiment is not limited to this. For greater simplicity and convenience, the present embodiment uses the first radiation port P1, the second radiation port P2, and the third radiation port P3 as examples for explanation, and should not be construed as limiting the present embodiment.

[0206] Compared to the third radiation port P3, the first radiation port P1 and the second radiation port P2 are located closer to the center of the narrow sidewall of the first waveguide cavity. The distance between the radiating end of the third radiation port P3 and the radiating end of the first radiation port P1 is a third distance (i.e., s3), and the distance between the connection end of the third radiation port P3 and the first waveguide cavity and the connection end of the first radiation port P1 and the first waveguide cavity is a fourth distance (i.e., s4). In this case, regardless of whether the third distance (s3) is less than, equal to, or greater than the fourth distance (s4), the grating lobe of the waveguide antenna can be suppressed to a certain extent, thereby reducing the sidelobe level of the waveguide antenna.

[0207] It can be understood that the above-mentioned radiation end and connection end refer to different parts into which the radiation port is divided according to the relative distance relationship with the first waveguide cavity. Specifically, the radiation end can refer to an end of the radiation port that is relatively far away from the first waveguide cavity, and the connection end can refer to an end of the radiation port that is relatively close to the first waveguide cavity.

[0208] It can be understood that the distance between the third radiation port P3 and the first radiation port P1 in the embodiment of the present application, whether it gradually becomes smaller, remains unchanged, or increases in the direction of radiation of the signal through the radiation port, can to a certain extent suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0209] It can be understood that the effect of suppressing the waveguide antenna grating lobe corresponding to the third spacing (s3) being smaller than the fourth spacing (s4) is better than the effect of suppressing the waveguide antenna grating lobe corresponding to the third spacing (s3) being larger than the fourth spacing (s4), thereby reducing the effect of the side lobe level of the waveguide antenna. That is, the effect of suppressing the waveguide antenna grating lobe that gradually becomes smaller in the direction in which the signal is radiated through the radiation port is better than the effect of suppressing the waveguide antenna grating lobe that gradually becomes larger in the direction in which the signal is radiated through the radiation port, thereby reducing the side lobe level of the waveguide antenna.

[0210] It is understood that the first direction (z-direction) and the third direction (y-direction) in Figure 7 are perpendicular to each other, and the plane formed by the first direction (z-direction) and the third direction (y-direction) is perpendicular to the second direction (x-direction). In this case, the first direction (z-direction) is the direction in which the signal is radiated through the radiation port, the second direction (x-direction) is perpendicular to the wide sidewall of the first waveguide cavity, and the third direction (y-direction) is parallel to the wide sidewall of the first waveguide cavity.

[0211] Optionally, the waveguide device may further include an input waveguide for inputting a signal into the first waveguide cavity. Optionally, the input waveguide may also be another form of feeding structure for feeding a signal into the first waveguide cavity, which is not limited in this embodiment of the present application.

[0212] Furthermore, the third radiation port P3 includes a fifth sub-radiation section q5 and a sixth sub-radiation section q6 that are connected;

[0213] The fifth sub-radiation segment q5 is a radiation segment close to the first waveguide cavity, and the sixth sub-radiation segment q6 is a radiation segment far away from the first waveguide cavity;

[0214] The distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 is less than or equal to the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1; or,

[0215] The distance between the sixth sub-radiation section q6 and the second sub-radiation section q2 is greater than the distance between the fifth sub-radiation section q5 and the first sub-radiation section q1.

[0216] The aforementioned sub-radiation segments refer to different sections of the radiation port divided by their relative proximity to the first waveguide cavity. Specifically, the fifth sub-radiation segment q5 may refer to the radiation segment closest to the first waveguide cavity, and the sixth sub-radiation segment q6 may refer to the radiation segment farther from the first waveguide cavity. Furthermore, the spacing between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 (i.e., spacing s3) is less than, equal to, or greater than the spacing between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 (i.e., spacing s4).

[0217] It can be understood that the third radiation port P3 and the first radiation port P1 in the embodiment of the present application can include multiple (two or more) connected sub-radiation segments, and the multiple connected sub-radiation segments must meet the following conditions: the spacing between the sub-radiation segments of the third radiation port P3 and the first radiation port P1 away from the waveguide cavity can be less than or equal to the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity.

[0218] It can be understood that the effect of suppressing the waveguide antenna grating lobe corresponding to the spacing between the sub-radiation segments of the third radiation port P3 and the first radiation port P1 away from the waveguide cavity is smaller than the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity is better than the effect of suppressing the waveguide antenna grating lobe corresponding to the spacing between the sub-radiation segments of the third radiation port P3 and the first radiation port P1 away from the waveguide cavity is larger than the spacing between the sub-radiation segments of the two radiation ports close to the waveguide cavity.

[0219] Optionally, the distance between the second sub-radiation section q2 and the fourth sub-radiation section q4 is smaller than the distance between the second sub-radiation section q2 and the sixth sub-radiation section q6.

[0220] Since the first radiation port and the second radiation port are distributed on the narrow side wall of the first waveguide cavity, they are closer to the center of the narrow side wall of the first waveguide cavity than the third radiation port is distributed on the narrow side wall of the first waveguide cavity. Therefore, in the embodiment of the present application, by setting the spacing between the second sub-radiation segment and the fourth sub-radiation segment to be smaller than the spacing between the second sub-radiation segment and the sixth sub-radiation segment, the grating lobe of the waveguide antenna can be suppressed, thereby reducing the side lobe level of the waveguide antenna.

[0221] In addition, the following will also describe the situations where the distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 is less than, equal to, or greater than the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 in conjunction with Figures 8A to 8D.

[0222] Please refer to Figures 8A to 8D, which are schematic plan views of a waveguide device according to an embodiment of the present application. It is understood that the waveguide device shown in Figures 8A to 8D can be implemented as a separate embodiment; alternatively, the waveguide device shown in Figures 8A to 8D can be understood as a variation or supplement to the waveguide device shown in Figures 5, 6, or 7. In this case, Figures 8A to 8D can be understood as plan views of the waveguide device shown in Figure 4 in the second direction (x direction).

[0223] As shown in FIG8A to FIG8D , the distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 and the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 are as follows:

[0224] Case 1:

[0225] As shown in Figure 8A, multiple radiation ports are evenly distributed on the narrow side wall of the first waveguide cavity, including but not limited to the first radiation port P1, the second radiation port P2, and the third radiation port P3. Compared with the third radiation port P3, the first radiation port P1 and the second radiation port P2 are distributed closer to the center of the narrow side wall of the first waveguide cavity.

[0226] The first sub-radiation segment q1 in the first radiation port P1, the third sub-radiation segment q3 in the second radiation port P2, and the fifth sub-radiation segment q5 in the third radiation port P3 remain in position unchanged, the fourth sub-radiation segment q4 in the second radiation port P2 is offset to the left by a certain distance in the third direction (y direction), the second sub-radiation segment q2 in the first radiation port P1 is offset to the right by a distance i1 in the third direction (y direction), and the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the right by a distance i2 in the third direction (y direction).

[0227] When i1 is smaller than i2, the distance that the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the right in the third direction (y direction) is greater than the distance that the second sub-radiation segment q2 in the first radiation port P1 is offset to the right in the third direction (y direction), so that the distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 (i.e., distance s3) is smaller than the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 (i.e., distance s4), which can suppress the grating lobe of the waveguide antenna and thus reduce the side lobe level of the waveguide antenna.

[0228] Case 2:

[0229] As shown in Figure 8B, multiple radiation ports are evenly distributed on the narrow side wall of the first waveguide cavity, including but not limited to the first radiation port P1, the second radiation port P2, and the third radiation port P3. Compared with the third radiation port P3, the first radiation port P1 and the second radiation port P2 are distributed closer to the center of the narrow side wall of the first waveguide cavity.

[0230] The first sub-radiation segment q1 in the first radiation port P1, the third sub-radiation segment q3 in the second radiation port P2, and the fifth sub-radiation segment q5 in the third radiation port P3 remain in position unchanged, the fourth sub-radiation segment q4 in the second radiation port P2 is offset to the left by a certain distance in the third direction (y direction), the second sub-radiation segment q2 in the first radiation port P1 is offset to the right by a distance i1 in the third direction (y direction), and the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the right by a distance i2 in the third direction (y direction), and i1 is smaller than i2.

[0231] When i1 is equal to i2, the distance that the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the right in the third direction (y direction) is equal to the distance that the second sub-radiation segment q2 in the first radiation port P1 is offset to the right in the third direction (y direction), so that the distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 (i.e., distance s3) is equal to the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 (i.e., distance s4).

[0232] At this time, since the distance between the first radiation port P1 and the second radiation port P2 distributed closer to the center of the narrow side wall of the first waveguide cavity becomes smaller in the first direction (z direction), the grating lobe of the waveguide antenna can still be suppressed to a certain extent, thereby reducing the side lobe level of the waveguide antenna.

[0233] Case 3:

[0234] As shown in Figure 8C, multiple radiation ports are evenly distributed on the narrow side wall of the first waveguide cavity, including but not limited to the first radiation port P1, the second radiation port P2, and the third radiation port P3. Compared with the third radiation port P3, the first radiation port P1 and the second radiation port P2 are distributed closer to the center of the narrow side wall of the first waveguide cavity.

[0235] The first sub-radiation segment q1 in the first radiation port P1, the third sub-radiation segment q3 in the second radiation port P2, and the fifth sub-radiation segment q5 in the third radiation port P3 remain in position unchanged, the fourth sub-radiation segment q4 in the second radiation port P2 is offset to the left by a certain distance in the third direction (y direction), the second sub-radiation segment q2 in the first radiation port P1 is offset to the right by a distance i1 in the third direction (y direction), and the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the right by a distance i2 in the third direction (y direction), and i1 is smaller than i2.

[0236] When i1 is greater than i2, the distance that the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the right in the third direction (y direction) is smaller than the distance that the second sub-radiation segment q2 in the first radiation port P1 is offset to the right in the third direction (y direction), so that the distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 (i.e., distance s3) is greater than the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 (i.e., distance s4).

[0237] In particular, when i1 is greater than i2 and i2 is 0, the sixth sub-radiation segment q6 in the third radiation port P3 does not shift, and the distance between the sixth sub-radiation segment q6 and the second sub-radiation segment q2 (i.e., distance s3) is also greater than the distance between the fifth sub-radiation segment q5 and the first sub-radiation segment q1 (i.e., distance s4).

[0238] At this time, since the distance between the first radiation port P1 and the second radiation port P2 distributed closer to the center of the narrow side wall of the first waveguide cavity becomes smaller in the first direction (z direction), the grating lobe of the waveguide antenna can still be suppressed to a certain extent, thereby reducing the side lobe level of the waveguide antenna.

[0239] Case 4:

[0240] As shown in Figure 8D, multiple radiation ports are evenly distributed on the narrow side wall of the first waveguide cavity, including but not limited to the first radiation port P1, the second radiation port P2, and the third radiation port P3. Compared with the third radiation port P3, the first radiation port P1 and the second radiation port P2 are distributed closer to the center of the narrow side wall of the first waveguide cavity.

[0241] The first sub-radiation segment q1 in the first radiation port P1, the third sub-radiation segment q3 in the second radiation port P2, and the fifth sub-radiation segment q5 in the third radiation port P3 remain in position unchanged, the fourth sub-radiation segment q4 in the second radiation port P2 is offset to the left by a certain distance in the third direction (y direction), the second sub-radiation segment q2 in the first radiation port P1 is offset to the right by a distance i1 in the third direction (y direction), and the sixth sub-radiation segment q6 in the third radiation port P3 is offset to the left by a distance i2 in the third direction (y direction).

[0242] When i2 is greater than 0, the distance between the sixth sub-radiation section q6 and the second sub-radiation section q2 (ie, distance s3) is greater than the distance between the fifth sub-radiation section q5 and the first sub-radiation section q1 (ie, distance s4).

[0243] At this time, since the distance between the first radiation port P1 and the second radiation port P2 distributed closer to the center of the narrow side wall of the first waveguide cavity becomes smaller in the first direction (z direction), the grating lobe of the waveguide antenna can still be suppressed to a certain extent, thereby reducing the side lobe level of the waveguide antenna.

[0244] It can be understood that the effects of the above-mentioned situations 1 to 4 on suppressing the grating lobes of the waveguide antenna and reducing the side lobe levels of the waveguide antenna are weakened successively, but they can all suppress the grating lobes of the waveguide antenna and reduce the side lobe levels of the waveguide antenna to a certain extent.

[0245] It can be understood that the above four situations are only a few possible illustrative descriptions and should not be used to limit the embodiments of the present application. The embodiments obtained based on the supplement or reasonable deformation of the above exemplary situations all fall within the scope of protection of the embodiments of the present application.

[0246] In a possible embodiment, in FIG. 6 , FIG. 7 , and FIG. 8A to FIG. 8D , the interval s1 between the second sub-radiation segment q2 and the fourth sub-radiation segment q4 satisfies the following condition: 0.35λ0≤s1≤0.6λ0;

[0247] Among them, λ0 represents the wavelength of electromagnetic waves in vacuum.

[0248] 6, 7, 8A to 8D, the spacing s1 between the second sub-radiation segment q2 and the fourth sub-radiation segment q4 meets the above conditions, which can suppress the grating lobe of the waveguide antenna, thereby reducing the sidelobe level of the waveguide antenna.

[0249] In a possible embodiment, in FIG. 6 , FIG. 7 , and FIG. 8A to FIG. 8D , the interval s2 between the first sub-radiation section q1 and the third sub-radiation section q3 satisfies the following condition: 0.4λ g ≤s2≤0.6λ g ;

[0250] Among them, λ g Characterizes the wavelength of the electromagnetic wave transmitted in the first waveguide cavity.

[0251] 6, 7, 8A to 8D, the spacing s2 between the first sub-radiation segment q1 and the third sub-radiation segment q3 meets the above conditions, which can suppress the grating lobe of the waveguide antenna, thereby reducing the sidelobe level of the waveguide antenna.

[0252] In a possible embodiment, in FIG. 5 , the signal in the first waveguide cavity is radiated from the first radiation port P1 and the second radiation port P2 along the first direction through the first surface of the first waveguide cavity.

[0253] The width of the first surface in the second direction (x direction) is the same as the width of the radiation port, the length of the first surface in the third direction (y direction) is the same as the length of the first waveguide cavity, and the first direction (z direction), the second direction (x direction) and the third direction (y direction) are perpendicular to each other.

[0254] Specifically, referring to Figure 5 , the first radiation port P1 and the second radiation port P2 are located on the narrow sidewall of the first waveguide cavity (i.e., the first surface of the first waveguide cavity). Signals within the first waveguide cavity are radiated from the first radiation port P1 and the second radiation port P2 along a first direction (z-direction) through the first surface of the first waveguide cavity. It will be appreciated that the first direction (z-direction), the second direction (x-direction), and the third direction (y-direction) are mutually perpendicular, forming a three-dimensional space.

[0255] Through the embodiments of the present application, the first radiation port P1 and the second radiation port P2 are distributed on the narrow side wall of the first waveguide cavity. The signal in the first waveguide cavity is radiated from the first radiation port P1 and the second radiation port P2 along the first direction (z direction) through the narrow side wall of the first waveguide cavity, which can improve the radiation efficiency of the signal.

[0256] In a possible embodiment, in the above-mentioned Figures 5 to 7 and 8A to 8D, the three-dimensional dimensions L1, a1, and b1 of the first waveguide cavity satisfy the following conditions: 0.85×(N×λ g / 2)≤L1≤1.15×(N×λ g / 2), 0 <a1≤0.5λ g , 0.5λ g ≤b1≤λ g ;

[0257] Among them, λ g Characterizes the wavelength of the electromagnetic wave transmitted in the first waveguide cavity, and N is the number of radiation ports.

[0258] For details, see Figures 5 to 7 and 8A to 8D. L1 represents the length of the first waveguide cavity in the third direction (y-direction), a1 represents the width of the first waveguide cavity in the second direction (x-direction), and b1 represents the height of the first waveguide cavity in the first direction (z-direction). The three-dimensional dimensions L1, a1, and b1 of the first waveguide cavity satisfying these conditions can achieve a steady-state field distribution within the first waveguide cavity, thereby improving signal transmission efficiency within the first waveguide cavity.

[0259] Optionally, the following describes the conditions satisfied by the dimensions a1, b1, and L1 of the first waveguide cavity in combination with the steady-state field distribution principle of the first waveguide cavity, as follows:

[0260] The right-angle components of the electromagnetic field of the electromagnetic wave in the first waveguide cavity all satisfy the Helmholtz equation: u(x,y,z)=X(x)Y(y)Z(z)

[0261] From the metal boundary conditions, we can get: E x =A1cos k x x sin k y y sin k z z E y =A2cos k y y sin k x x sin k z z E z =A3cos k z z sin k y y sin k x x

[0262] According to the boundary conditions of the first waveguide cavity dimensions a1, b1, and L1, K×(a1, b1, L1) must be an integer multiple of π, so:

[0263] Where m, n, p = 0, 1, 2, 3, ...; Substitute it into The resonant frequency can be obtained as:

[0264] Among them, ω mnn is the local oscillator frequency of the first waveguide cavity, p mnp is the resonant frequency of the first waveguide cavity.

[0265] When the lowest resonant frequency of the first waveguide cavity is m,n,p=1,1,0, we have:

[0266] The corresponding wavelength is:

[0267] In the embodiment of the present application, assuming that the resonant frequency is 76.5 GHz, m,n,p=1,2*N-1,0, where N is the number of radiation ports, the length L1 of the first waveguide cavity in the third direction (y direction) can be obtained by reverse calculation.

[0268] In a possible embodiment, in FIG. 5 to FIG. 7 and FIG. 8A to FIG. 8D , the distance d1 between the two first waveguide cavities in the waveguide device satisfies the following conditions: 0.5λ0≤d1≤1.5λ0;

[0269] Among them, λ0 represents the wavelength of electromagnetic waves in vacuum.

[0270] Through the embodiments of the present application, the spacing d1 between two (or more) first waveguide cavities in the waveguide device meets the above conditions, which can simplify the feeding network, realize the small-pitch array of the waveguide antenna array, reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0271] In a possible embodiment, in the above-mentioned Figures 5 to 7, 8A to 8D, and 9A to 9B, the first waveguide cavity has a bending structure, and the bending structure is used to connect the first radiation port and the second radiation port.

[0272] The bending structure may be a straight bending or a curved bending (for example, including but not limited to a triangular waveform, a sine waveform, a cosine waveform, etc.), and the embodiment of the present application does not limit this.

[0273] Through the embodiments of the present application, a straight waveguide is transformed into a waveguide with a bent structure and a radiation port is designed on the narrow side wall. This can reduce the spatial distance of the radiation port within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0274] Furthermore, the cross-sectional dimensions x1 and y1 of the bending structure in the first direction (z direction) satisfy the following conditions: 0.15λ g ≤x1≤0.35λ g , 0.65λ g ≤y1≤0.85λ g ;

[0275] Wherein, x1 is the length of the bending structure in the second direction (x direction), and y1 is the length of the bending structure in the third direction (y direction).

[0276] Through the embodiments of the present application, the cross-sectional dimensions x1 and y1 of the bending structure in the first direction (z direction) meet the above conditions, which can reduce the spatial distance of the radiation port within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0277] Optionally, in order to achieve the reduction in the distance between the radiation ports in the waveguide devices shown in Figures 5 to 7 and Figures 8A to 8D in the direction of signal radiation, the embodiments of the present application also provide several waveguide devices including radiation ports of other structural forms.

[0278] For details, please refer to Figures 9A and 9B, which are schematic plan views of a waveguide device according to an embodiment of the present application. It is understood that the waveguide device shown in Figures 9A and 9B can be implemented as a separate embodiment; alternatively, the waveguide device shown in Figures 9A and 9B can be understood as a variation or supplement to the waveguide device shown in Figures 5 to 7 and 8A to 8D. In this case, Figures 9A and 9B can be understood as a plan view of the waveguide device shown in Figure 4 in the second direction (x direction) after a reasonable deformation.

[0279] As shown in FIG9A , the distance between the radiation ports in the waveguide device becomes smaller in the direction of signal radiation, which can suppress the grating lobe of the waveguide antenna and reduce the side lobe level of the waveguide antenna.

[0280] It can be understood that, unlike the morphological structure of the radiation port of the waveguide device in Figures 5 to 7 and Figures 8A to 8D above, the radiation port of the waveguide device in the embodiment of the present application has a sub-radiation segment close to the first waveguide cavity and a length in the third direction (y direction) that is greater than the length of the sub-radiation segment away from the first waveguide cavity in the third direction (y direction).

[0281] As shown in FIG9B , the distance between the radiation ports in the waveguide device becomes smaller in the direction of signal radiation, which can suppress the grating lobe of the waveguide antenna and reduce the side lobe level of the waveguide antenna.

[0282] It can be understood that, unlike the morphological structure of the radiation port of the waveguide device in Figures 5 to 7, 8A to 8D, and 9A above, the surface of the radiation port of the waveguide device in the embodiment of the present application is smooth, and can be regarded as differentiating the radiation port into multiple connected sub-radiation segments, and these sub-radiation segments are smoothly connected to form an inclined radiation port.

[0283] In a possible embodiment, in the above-mentioned Figures 5 to 7, 8A to 8D, and 9A to 9B, the side lobe level of the directivity pattern corresponding to the waveguide device is less than the first threshold.

[0284] The first threshold value in the embodiments of the present application is not a fixed value and can be adjusted according to different application scenarios. For example, the waveguide device in the embodiments of the present application has a significant advantage in radiation efficiency compared to a traditional PCB printed antenna. In this case, by adjusting the first threshold value, the sidelobe level of the radiation pattern corresponding to the waveguide device can be reduced to a level lower than that of the radiation pattern corresponding to the traditional PCB printed antenna.

[0285] For details, please refer to Figures 10A, 10B, 11A and 11B. Figures 10A and 11A are schematic diagrams of signal distribution of the waveguide device provided in an embodiment of the present application, and Figures 10B and 11B are schematic diagrams of the effect of the radiation pattern provided in an embodiment of the present application.

[0286] As shown in FIG. 10A and FIG. 11A , it can be seen that FIG. 10A is the signal distribution corresponding to the waveguide device shown in FIG. 4 , and FIG. 11A is the signal distribution corresponding to the waveguide device shown in FIG. 5 .

[0287] By comparing Figure 10A and Figure 11A, it can be seen that by setting the distance between the radiating ends of the two radiating ports to be smaller than the distance between the connecting ends of the two radiating ports and the waveguide cavity, the sidelobe level of the series-fed waveguide antenna can be reduced, and the advantage of the waveguide antenna in radiation transmission efficiency can be guaranteed.

[0288] As shown in FIG. 10B and FIG. 11B , it can be seen that FIG. 10B is a radiation pattern corresponding to the waveguide device shown in FIG. 4 , and FIG. 11B is a radiation pattern corresponding to the waveguide device shown in FIG. 5 .

[0289] By comparing Figure 10B and Figure 11B, it can be seen that by setting the distance between the radiating ends of the two radiating ports to be smaller than the distance between the connecting ends of the two radiating ports and the waveguide cavity, the normal gain of the antenna is basically unchanged, but the sidelobe level of the V-plane radiation pattern is improved from -10dB to -14dB, which can reduce the sidelobe level of the series-fed waveguide antenna and ensure the advantage of the waveguide antenna in radiation transmission efficiency.

[0290] Please refer to FIG. 12 , which is a schematic structural diagram of a waveguide device provided in an embodiment of the present application.

[0291] As shown in FIG12 , the waveguide device includes:

[0292] A second waveguide cavity, M radiation ports, where M is an integer greater than 1;

[0293] The signal in the second waveguide cavity is radiated through M radiation ports;

[0294] The second waveguide cavity has a bending structure, and the bending structure is used to connect M radiation ports.

[0295] The bending structure may be a straight bending or a curved bending (for example, including but not limited to a triangular waveform, a sine waveform, a cosine waveform, etc.), and the embodiment of the present application does not limit this.

[0296] It can be understood that the waveguide device shown in Figure 12 includes four radiation ports, which is only used as a possible exemplary illustration. The waveguide device can also include more or fewer radiation ports, and the embodiments of the present application do not limit this.

[0297] It can be understood that the bending structure used to connect M radiation ports in the embodiment of the present application can reduce the spatial distance between the radiation ports within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, and thus reduce the side lobe level of the waveguide antenna.

[0298] It can be understood that the first direction (z-direction), the second direction (x-direction), and the third direction (y-direction) in FIG12 are mutually perpendicular to each other to form a three-dimensional space. In this case, the first direction (z-direction) is the direction in which the signal is radiated through the radiation port, the second direction (x-direction) is perpendicular to the wide sidewall of the second waveguide cavity, and the third direction (y-direction) is parallel to the wide sidewall of the second waveguide cavity.

[0299] Optionally, the waveguide device may further include an input waveguide for inputting a signal into the first waveguide cavity. Optionally, the input waveguide may also be another form of feeding structure for feeding a signal into the first waveguide cavity, which is not limited in this embodiment of the present application.

[0300] The current parallel-fed waveguide antenna (as shown in Figure 3) has a complex three-dimensional structure, high machining precision requirements, and high machining costs. However, the present embodiment transforms a straight waveguide into a waveguide with a curved structure and then designs a radiation port on the narrow sidewall. This can reduce the spatial distance of the radiation port within the entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, and thus reduce the sidelobe level of the waveguide antenna, thereby maintaining the waveguide antenna's advantage in radiation transmission efficiency, thereby realizing a series-fed waveguide antenna with low sidelobe level.

[0301] Compared with the current parallel-fed waveguide antenna, the waveguide device in the embodiment of the present application adopts a series-fed waveguide with a simpler feeding form, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs. In addition, by reducing the sidelobe level of the series-fed waveguide antenna, the advantages of the waveguide antenna in radiation transmission efficiency can be guaranteed.

[0302] Optionally, in combination with the antenna array element spacing and sidelobe level principles, the effect of achieving a low sidelobe level of a series-fed waveguide antenna by reducing the spatial distance of the radiation port is explained. Please refer to the introduction to the antenna array element spacing and sidelobe level principles of the waveguide device in Figure 5 above, which will not be repeated here.

[0303] For details, please refer to Figure 13, which is a plan view of a waveguide device provided in an embodiment of the present application. It is understood that the waveguide device shown in Figure 13 can be implemented as a separate embodiment; alternatively, the waveguide device shown in Figure 13 can be understood as a variation or supplement to the waveguide device shown in Figure 12 above. In this case, Figure 13 can be understood as a top view of the waveguide device shown in Figure 12 above in the first direction (z direction).

[0304] As shown in FIG13 , the waveguide device includes:

[0305] A second waveguide cavity, M radiation ports, where M is an integer greater than 1;

[0306] The signal in the second waveguide cavity is radiated through M radiation ports;

[0307] The second waveguide cavity has a bending structure, and the bending structure is used to connect M radiation ports.

[0308] The bending structure may be a straight bending or a curved bending (for example, including but not limited to a triangular waveform, a sine waveform, a cosine waveform, etc.), which is not limited in the embodiment of the present application.

[0309] It can be understood that the waveguide device shown in Figure 13 includes four radiation ports, which is only a possible exemplary illustration. The waveguide device can also include more or fewer radiation ports, and the embodiments of the present application do not limit this.

[0310] It can be understood that the bending structure used to connect M radiation ports in the embodiment of the present application can reduce the spatial distance between the radiation ports within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, and thus reduce the side lobe level of the waveguide antenna.

[0311] In a possible embodiment, in FIG. 12 and FIG. 13 , the signal in the second waveguide cavity is radiated from the M radiation ports along the first direction through the first surface of the second waveguide cavity.

[0312] The width of the first surface in the second direction (x direction) is the same as the width of the radiation port, the length of the first surface in the third direction (y direction) is the same as the length of the second waveguide cavity, and the first direction (z direction), the second direction (x direction) and the third direction (y direction) are perpendicular to each other.

[0313] Specifically, referring to Figures 12 and 13 , M radiation ports are distributed along the narrow sidewall of the second waveguide cavity (i.e., the first surface of the second waveguide cavity). Signals within the second waveguide cavity are radiated from the M radiation ports along a first direction (z-direction) through the first surface of the second waveguide cavity. It will be appreciated that the first (z-direction), the second (x-direction), and the third (y-direction) are mutually perpendicular, forming a three-dimensional space.

[0314] According to the embodiment of the present application, M radiation ports are distributed on the narrow sidewall of the second waveguide cavity, and the signal in the second waveguide cavity is radiated from the M radiation ports along the first direction through the narrow sidewall of the second waveguide cavity, thereby improving the radiation efficiency of the signal.

[0315] In a possible embodiment, in FIG. 12 and FIG. 13 , the cross-sectional dimensions x2 and y2 of the bending structure in the first direction (z direction) satisfy the following conditions: 0.15λ g ≤x2≤0.35λ g , 0.65λ g ≤y2≤0.85λ g ;

[0316] 13 , x2 is the length of the bending structure in the second direction (x direction), and y2 is the length of the bending structure in the third direction (y direction).

[0317] Through the embodiments of the present application, the cross-sectional dimensions x2 and y2 of the bending structure in the first direction (z direction) meet the above conditions, which can reduce the spatial distance of the radiation port within an entire waveguide wavelength, suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0318] In a possible embodiment, in FIG. 12 and FIG. 13 , the three-dimensional dimensions L2, a2, and b2 of the second waveguide cavity satisfy the following conditions: 0.85×(M×λ g / 2)≤L2≤1.15×(M×λ g / 2,0 <a2≤0.5λ g , 0.5λ g ≤b2≤λ g ;

[0319] Among them, λ g Characterizing the wavelength of the electromagnetic wave transmitted in the second waveguide cavity;

[0320] For details, see Figures 12 and 13 . L2 represents the length of the second waveguide cavity in the third direction (y-direction), a2 represents the width of the second waveguide cavity in the second direction (x-direction), and b2 represents the height of the second waveguide cavity in the first direction (z-direction). The three-dimensional dimensions L2, a2, and b2 of the second waveguide cavity satisfying the aforementioned conditions can achieve a steady-state field distribution within the second waveguide cavity, thereby improving signal transmission efficiency within the second waveguide cavity.

[0321] Optionally, the conditions satisfied by the dimensions a2, b2, and L2 of the second waveguide cavity are described in combination with the steady-state field distribution principle of the second waveguide cavity. Please refer to the introduction of the steady-state field distribution principle of the first waveguide cavity above, which will not be repeated here.

[0322] In a possible embodiment, in FIG. 12 and FIG. 13 , the spacing s3 between two adjacent radiation ports among the M radiation ports satisfies the following condition: 0.35λ0≤s3≤0.6λ0;

[0323] Among them, λ0 represents the wavelength of electromagnetic waves in vacuum.

[0324] Through the embodiment of the present application, the spacing s3 between two adjacent radiation ports among the M radiation ports meets the above conditions, which can suppress the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna.

[0325] Optionally, in order to reduce the spatial distance of the radiation ports within an entire waveguide wavelength in the waveguide devices shown in FIG. 12 and FIG. 13 , the embodiments of the present application also provide several waveguide devices including waveguide cavities with other structural forms.

[0326] For details, please refer to Figures 14A to 14D (i.e., Figures 14A, 14B, 14C, and 14D), which are plan views of a waveguide device according to an embodiment of the present application. It is understood that the waveguide device shown in Figures 14A to 14D can be implemented as a separate embodiment; alternatively, the waveguide device shown in Figures 14A to 14D can be understood as a variation or supplement to the waveguide device shown in Figures 12 and 13 . In this case, Figures 14A to 14D can be understood as a top view of the waveguide device shown in Figure 12 in the first direction (z direction) after a suitable deformation.

[0327] As shown in Figures 14A to 14D, the bending structure used to connect multiple radiation ports can reduce the spatial distance between the radiation ports within an entire waveguide wavelength, suppress the grating lobes of the waveguide antenna, thereby reducing the sidelobe level of the waveguide antenna and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0328] It can be understood that, unlike the morphological structure of the waveguide cavity of the waveguide device in Figures 12 and 13 above, the waveguide cavity of the waveguide device in the embodiment of the present application reduces the spatial distance of the radiation port within an entire waveguide wavelength by including multiple bending structures. The bending structure can be a straight bend or a curved bend (for example, including but not limited to a triangular waveform, a sine waveform, a cosine waveform, etc.), and the embodiment of the present application does not limit this.

[0329] In a possible embodiment, in the above-mentioned Figures 12 to 13 and Figures 14A to 14D, the side lobe level of the directivity pattern corresponding to the waveguide device is less than the second threshold.

[0330] The second threshold value in the embodiments of the present application is not a fixed value and can be adjusted according to different application scenarios. For example, the waveguide device in the embodiments of the present application has a significant advantage in radiation efficiency compared to a traditional PCB printed antenna. In this case, the second threshold value can be adjusted to make the sidelobe level of the radiation pattern corresponding to the waveguide device lower than the sidelobe level of the radiation pattern corresponding to the traditional PCB printed antenna.

[0331] For details, please refer to Figures 15A and 15B. Figure 15A is a schematic diagram of the signal distribution of the waveguide device provided in an embodiment of the present application, and Figure 15B is a schematic diagram of the effect of the radiation pattern provided in an embodiment of the present application.

[0332] As shown in FIG. 15A , it can be seen that FIG. 15A shows the signal distribution corresponding to the waveguide device shown in FIG. 12 .

[0333] By comparing FIG15A with FIG10A above, it can be seen that by transforming the straight waveguide into a waveguide with a bent structure and then designing a radiation port on the narrow side wall, the spatial distance of the radiation port can be reduced within an entire waveguide wavelength, suppressing the grating lobe of the waveguide antenna, thereby reducing the side lobe level of the waveguide antenna and ensuring the advantage of the waveguide antenna in radiation transmission efficiency.

[0334] As shown in FIG. 15B , it can be seen that FIG. 15B is the radiation pattern corresponding to the waveguide device shown in FIG. 12 .

[0335] By comparing FIG15B with FIG10B above, it can be seen that by transforming the straight waveguide into a waveguide with a bent structure and then designing a radiation port on the narrow side wall, the spatial distance of the radiation port can be reduced within an entire waveguide wavelength. The normal gain of the antenna remains basically unchanged, and the sidelobe level of the V-plane radiation pattern is improved from -10dB to -19dB, an improvement of 9dB. This can reduce the sidelobe level of the waveguide antenna and ensure the advantage of the waveguide antenna in radiation transmission efficiency.

[0336] In a possible embodiment, in FIG. 12 to FIG. 13 and FIG. 14A to FIG. 14D , the spacing d2 between the two second waveguide cavities in the waveguide device satisfies the following conditions: 0.5λ0≤d2≤1.5λ0;

[0337] Among them, λ0 represents the wavelength of electromagnetic waves in vacuum.

[0338] For details, please refer to Figure 16, which is a schematic diagram of a waveguide antenna feeding network provided in an embodiment of the present application.

[0339] As shown in FIG16 , the waveguide device includes four second waveguide cavities, and the spacing between two adjacent second waveguide cavities in the four second waveguide cavities meets the above-mentioned condition d2, which can simplify the feeding network and realize the small-pitch arrangement of the waveguide antenna array.

[0340] For example, when d2 = 0.5λ0, the return loss and transmission isolation of the waveguide antenna feed network can be seen in Figures 17A and 17B. Figure 17A is a schematic diagram of the effect of return loss provided by an embodiment of the present application, and Figure 17B is a schematic diagram of the effect of transmission isolation provided by an embodiment of the present application.

[0341] As shown in FIG17A , the return loss SLL of the waveguide antenna feeding network is ≤ 15 dB;

[0342] As can be seen from FIG17B , the transmission isolation of the waveguide antenna feeding network is lso≤16dB.

[0343] Therefore, the extremely simple direct series feeding method makes it possible to arrange antenna units with a wavelength of 0.5λ0, and obtain the required impedance bandwidth and transmission isolation under the antenna array.

[0344] Through the embodiments of the present application, the spacing d2 between two (or more) second waveguide cavities in the waveguide device meets the above conditions, which can simplify the feeding network, realize the small-pitch array of the waveguide antenna array, reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs.

[0345] In addition, in a possible embodiment, a method for preparing a waveguide device is also provided. The specific process of the preparation method is as follows:

[0346] Method 1: A plastic layered mold can be formed to obtain a first waveguide cavity, a first radiation port, and a second radiation port. Electroplating is then performed on the surfaces of each mold, and finally, layer brazing is performed to obtain a waveguide device including the first waveguide cavity, the first radiation port, and the second radiation port. Alternatively, a plastic layered mold can be formed to obtain a second waveguide cavity and M radiation ports. Electroplating is then performed on the surfaces of each mold, and finally, layer brazing is performed to obtain a waveguide device including the second waveguide cavity and M radiation ports.

[0347] Among them, the process of plastic layered mold opening is as follows: the plastic is first heated and melted in the bottom of the injection molding machine, and then, pushed by the screw of the injection molding machine, enters the mold cavity through the injection molding machine nozzle and the mold pouring system. The plastic cools and hardens into shape, and the product is demolded to obtain the product.

[0348] Plastic electroplating is to cover the plastic surface with a metal layer to give it metallic properties. The specific process is: surface cleaning, solvent treatment, conditioning treatment, and sensitization.

[0349] Brazing refers to a method of joining metals by simultaneously heating a filler metal (a material below the melting point of the workpiece) and the workpiece to the filler metal's melting point. Liquid filler metal then fills the gap between the solid workpieces, creating a metallic connection. During brazing, the oxide film and oil stains on the contact surface of the parent metal must be removed to facilitate capillary action after the filler metal melts, increasing the filler metal's wettability and capillary flow.

[0350] Method 2: Alternatively, a first waveguide cavity, a first radiation port, and a second radiation port may be machined in layers, and then welded together to form a waveguide device. Alternatively, a second waveguide cavity and M radiation ports may be machined in layers, and then welded together to form a waveguide device.

[0351] The waveguide device obtained by the above preparation method adopts a series-fed waveguide with a simpler feeding form, which can reduce the complexity of the three-dimensional structure of the waveguide antenna, reduce the requirements for processing accuracy, and reduce processing costs. In addition, by reducing the sidelobe level of the series-fed waveguide antenna, the advantages of the waveguide antenna in radiation transmission efficiency can be guaranteed.

[0352] Illustratively, through the above-mentioned method for preparing the waveguide device, a waveguide device as shown in any one of Figures 5 to 7, 8A and 8D, 9A to 9B, 12 to 13, 14A to 14D, and 16 can be obtained. The structural characteristics and functional characteristics of the waveguide device can be found in the description of Figures 5 to 7, 8A and 8D, 9A to 9B, 12 to 13, 14A to 14D, and 16, and will not be repeated here.

[0353] The present application provides a radar or radar system including the waveguide device provided in the present application. It should be noted that there may be smart sensors that integrate multiple sensors. If the smart sensor includes millimeter wave detection capabilities, the smart sensor may also be referred to as a millimeter wave radar or millimeter wave radar system.

[0354] This application provides a terminal device that includes the waveguide device provided herein. For example, the terminal device can be a transportation vehicle, such as a car, truck, aircraft, drone, slow-moving transport vehicle, spacecraft, or ship, or any other vehicle used in any possible scenario. It can also be any device capable of carrying a millimeter wave detection device, such as surveying and mapping equipment. One or more waveguide devices provided herein are deployed on the terminal device.

[0355] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A waveguide device, characterized in that: include: a first waveguide cavity, a first radiation port and a second radiation port; The signal in the first waveguide cavity is radiated through the first radiation port and the second radiation port; The distance between the radiation ends of the first radiation port and the second radiation port is smaller than the distance between the connection ends of the first radiation port and the second radiation port and the first waveguide cavity.

2. The waveguide device according to claim 1, characterized in that The first radiation port includes a first sub-radiation segment and a second sub-radiation segment connected to each other, and the second radiation port includes a third sub-radiation segment and a fourth sub-radiation segment connected to each other; The first sub-radiation segment and the third sub-radiation segment are radiation segments close to the first waveguide cavity, and the second sub-radiation segment and the fourth sub-radiation segment are radiation segments far from the first waveguide cavity; The distance between the second sub-radiation segment and the fourth sub-radiation segment is smaller than the distance between the first sub-radiation segment and the third sub-radiation segment.

3. The waveguide device according to claim 1 or 2, characterized in that: The waveguide device further comprises: The third radiation port; The first radiation port is located between the second radiation port and the third radiation port; The signal in the first waveguide cavity is also radiated through the third radiation port; The distance between the third radiation port and the radiation end of the first radiation port is less than or equal to the distance between the third radiation port and the connection end of the first radiation port and the first waveguide cavity; or, The distance between the third radiation port and a radiation end of the first radiation port is greater than the distance between the third radiation port and a connection end of the first radiation port and the first waveguide cavity.

4. The waveguide device according to claim 3, characterized in that The third radiation port includes a fifth sub-radiation segment and a sixth sub-radiation segment connected to each other; The fifth sub-radiation segment is a radiation segment close to the first waveguide cavity, and the sixth sub-radiation segment is a radiation segment far from the first waveguide cavity; The distance between the sixth sub-radiation segment and the second sub-radiation segment is less than or equal to the distance between the fifth sub-radiation segment and the first sub-radiation segment; or, The distance between the sixth sub-radiation segment and the second sub-radiation segment is greater than the distance between the fifth sub-radiation segment and the first sub-radiation segment.

5. The waveguide device according to claim 4, characterized in that A distance between the second sub-radiation segment and the fourth sub-radiation segment is smaller than a distance between the second sub-radiation segment and the sixth sub-radiation segment.

6. The waveguide device according to any one of claims 2 to 5, characterized in that The interval s1 between the second sub-radiation segment and the fourth sub-radiation segment satisfies the following condition: 0.35λ0≤s1≤0.6λ0; Wherein, the λ0 represents the wavelength of the electromagnetic wave in a vacuum.

7. The waveguide device according to any one of claims 2 to 6, characterized in that The interval s2 between the first sub-radiation segment and the third sub-radiation segment satisfies the following condition: 0.4l g ≤s2≤0.6λ g ; Among them, the λ g Characterizes the wavelength of the electromagnetic wave transmitted in the first waveguide cavity.

8. The waveguide device according to any one of claims 1 to 7, characterized in that The signal in the first waveguide cavity is radiated through the first radiation port and the second radiation port, including: The signal in the first waveguide cavity is radiated from the first radiation port and the second radiation port along a first direction through the first surface of the first waveguide cavity; The width of the first surface in the second direction is the same as the width of the radiation port, the length of the first surface in the third direction is the same as the length of the first waveguide cavity, and the first direction, the second direction and the third direction are perpendicular to each other.

9. The waveguide device according to claim 8, characterized in that The three-dimensional dimensions L1, a1, and b1 of the first waveguide cavity satisfy the following conditions: 0.85×(N×λ g / 2)≤L1≤1.15×(N×λ g / 2),0 <a1≤0.5λ g ,0.5l g ≤b1≤λ g ; Among them, the λ g Characterizes the wavelength of the electromagnetic wave transmitted in the first waveguide cavity, and N is the number of radiation ports; The L1 is the length of the first waveguide cavity in the third direction, the a1 is the width of the first waveguide cavity in the second direction, and the b1 is the height of the first waveguide cavity in the first direction.

10. The waveguide device according to any one of claims 1 to 9, characterized in that The distance d1 between the two first waveguide cavities in the waveguide device satisfies the following condition: 0.5λ0≤d1≤1.5λ0; Wherein, the λ0 represents the wavelength of the electromagnetic wave in a vacuum.

11. The waveguide device according to any one of claims 1 to 10, characterized in that The first waveguide cavity has a bending structure, and the bending structure is used to connect the first radiation port and the second radiation port.

12. The waveguide device according to claim 11, characterized in that The cross-sectional dimensions x1 and y1 of the bending structure in the first direction satisfy the following conditions: 0.15 min g ≤x1≤0.35λ g ,0.65l g ≤y1≤0.85λ g ; Wherein, the x1 is the length of the bending structure in the second direction, and the y1 is the length of the bending structure in the third direction.

13. The waveguide device according to any one of claims 1 to 12, characterized in that The side lobe level of the directivity pattern corresponding to the waveguide device is less than a first threshold.

14. A waveguide device, characterized in that: include: A second waveguide cavity, M radiation ports, where M is an integer greater than 1; The signal in the second waveguide cavity is radiated through the M radiation ports; The second waveguide cavity has a bending structure, and the bending structure is used to connect the M radiation ports.

15. The waveguide device according to claim 14, characterized in that The signal in the second waveguide cavity is radiated through the M radiation ports, including: The signal in the second waveguide cavity is radiated from the M radiation ports along a first direction through the first surface of the second waveguide cavity; The width of the first surface in the second direction is the same as the width of the radiation port, the length of the first surface in the third direction is the same as the length of the second waveguide cavity, and the first direction, the second direction and the third direction are perpendicular to each other.

16. The waveguide device according to claim 15, characterized in that The cross-sectional dimensions x2 and y2 of the bending structure in the first direction satisfy the following conditions: 0.15 min g ≤x2≤0.35λ g ,0.65l g ≤y2≤0.85λ g ; Wherein, x2 is the length of the bending structure in the second direction, and y2 is the length of the bending structure in the third direction.

17. The waveguide device according to claim 15 or 16, characterized in that The three-dimensional dimensions L2, a2, and b2 of the second waveguide cavity satisfy the following conditions: 0.85×(M×λ g / 2)≤L2≤1.15×(M×λ g / 2),0 <a2≤0.5λ g ,0.5l g ≤b2≤λ g ; Among them, the λ g Characterizing the wavelength of the electromagnetic wave transmitted in the second waveguide cavity; The L2 is the length of the second waveguide cavity in the third direction, the a2 is the width of the second waveguide cavity in the second direction, and the b2 is the height of the second waveguide cavity in the first direction.

18. The waveguide device according to any one of claims 14 to 17, characterized in that The distance d2 between the two second waveguide cavities in the waveguide device satisfies the following condition: 0.5λ0≤d2≤1.5λ0; Wherein, the λ0 represents the wavelength of the electromagnetic wave in a vacuum.

19. The waveguide device according to any one of claims 14 to 18, characterized in that The spacing s3 between two adjacent radiation ports among the M radiation ports satisfies the following condition: 0.35λ0≤s3≤0.6λ0; Wherein, the λ0 represents the wavelength of the electromagnetic wave in a vacuum.

20. The waveguide device according to any one of claims 14 to 19, characterized in that The side lobe level of the directivity pattern corresponding to the waveguide device is less than a second threshold.

21. A radar, characterized in that: The radar comprises the waveguide device according to any one of claims 1 to 13, or the waveguide device according to any one of claims 14 to 20.

22. A terminal device, characterized in that: The terminal device comprises the waveguide device according to any one of claims 1 to 13, or the waveguide device according to any one of claims 14 to 20, or the radar according to claim 21.

23. A vehicle end, characterized in that: The vehicle end includes the waveguide device described in any one of claims 1 to 13, or the waveguide device described in any one of claims 14 to 20, or the radar described in claim 21, or the terminal equipment described in claim 22.

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