Radar Antenna Assembly and Radar System

Abstract

A radar antenna assembly for a vehicle includes a feed horn configured to transmit and/or receive radar signals and a metallic component of the vehicle. The metallic component of the vehicle includes a curved or faceted surface portion, and the feed horn is positioned such that the curved or faceted surface portion forms a reflector for the feed horn.

Claims

1. A radar antenna assembly for a vehicle, the radar antenna assembly comprising: a feed horn configured to at least one of transmit or receive radar signals; and a metallic component of the vehicle, the metallic component of the vehicle comprising a curved or faceted surface portion, the feed horn positioned such that the curved or faceted surface portion forms a reflector for the feed horn.

2. The radar antenna assembly of claim 1, wherein: the metallic component forms at least a part of a crash beam, a bumper, a pillar, or a door of the vehicle.

3. The radar antenna assembly of claim 1, wherein: the feed horn is fixed to the metallic component of the vehicle.

4. The radar antenna assembly of claim 1, wherein: in a mounted state of the metallic component of the vehicle, the curved or faceted surface portion faces away from a center of the vehicle.

5. The radar antenna assembly of claim 1, wherein: the curved or faceted surface portion is cylindrically or elliptically shaped.

6. The radar antenna assembly of claim 1, wherein: the feed horn comprises a waveguide member configured to connect the feed horn to a radar circuit; and the metallic component of the vehicle comprises a passage through which the waveguide member is guided.

7. The radar antenna assembly of claim 6, wherein: the passage is located in a central region of the curved or faceted surface portion.

8. The radar antenna assembly of claim 6, wherein: the passage is located outside the curved or faceted surface portion.

9. The radar antenna assembly of claim 6, wherein the feed horn comprises: a plurality of individual antenna elements; and a plurality of waveguide members for respective connections of the plurality of individual antenna elements to the radar circuit.

10. The radar antenna assembly of claim 9, wherein: each waveguide member of the plurality of waveguide members is arranged in a common conduit that is guided through the passage.

11. The radar antenna assembly of claim 9, wherein: at least two individual antenna elements of the plurality of individual antenna elements are connected to separate transmitters of the radar circuit.

12. The radar antenna assembly of claim 1, wherein: the metallic component of the vehicle has a recess and an insert member insertable into the recess; and the insert member comprises the curved or faceted surface portion.

13. A radar system for a vehicle, the radar system comprising: a radar antenna assembly comprising: a feed horn configured to at least one of transmit or receive radar signals; and a metallic plate member comprising a curved or faceted surface portion, the metallic plate member configured for an insertion in a recess of a metallic component of the vehicle, the feed horn fixed to the metallic plate member such that the curved or faceted surface portion forms a reflector for the feed horn.

14. The radar system of claim 13, further comprising: the metallic component of the vehicle, wherein the metallic plate member is inserted in the recess of the metallic component of the vehicle.

15. The radar system of claim 13, further comprising: a radar circuit configured to at least one of generate or process radar signals, the radar circuit connected to the radar antenna assembly, wherein the radar circuit is configured for at least one of a multiplex operation, a multiple input multiple output (MIMO) operation, or a frequency scan operation of the radar antenna assembly.

16. The radar system of claim 13, further comprising: a radar circuit, wherein: the feed horn comprises a waveguide member configured to connect the feed horn to the radar circuit; and at least one of the metallic plate member of the radar antenna assembly or the metallic component of the vehicle comprises a passage through which the waveguide member is guided.

17. The radar antenna assembly of claim 16, wherein the feed horn comprises: a plurality of individual antenna elements; and a plurality of waveguide members for respective connections of the plurality of individual antenna elements to the radar circuit.

18. A vehicle comprising: a chassis; a body; and a radar antenna assembly comprising: a feed horn configured to at least one of transmit or receive radar signals; and a metallic component comprising a curved or faceted surface portion, the feed horn positioned such that the curved or faceted surface portion forms a reflector for the feed horn, the metallic component comprising a portion of at least one of the chassis or the body.

19. The vehicle of claim 18, wherein: the metallic component comprises a metallic plate member including the curved or faceted surface portion, the metallic plate member inserted in a recess of the metallic component of the vehicle; and the feed horn is fixed to the metallic plate member such that the curved or faceted surface portion forms the reflector for the feed horn.

20. The vehicle of claim 18, wherein: the metallic component has a surface area of at least 400 square centimeters (cm.sup.2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Example embodiments and functions of the present disclosure are described herein in conjunction with the following drawings, showing schematically:

[0029] FIG. 1 is a motor vehicle equipped with a radar system.

[0030] FIG. 2 is a radar antenna assembly according to a first embodiment in a perspective view.

[0031] FIG. 3 is the radar antenna assembly according to FIG. 2 in a sectional side view.

[0032] FIG. 4 is a radar antenna assembly according to a second embodiment.

DETAILED DESCRIPTION

[0033] FIG. 1 schematically depicts a motor vehicle 11, also called a host vehicle, and a radar system 13 mounted to a front portion of the motor vehicle 11. The radar system 13 is connected to an electronic processing device 15, for example an advanced driver assistance system or an autonomous driving system. In operation, the motor vehicle 11 is moving in a driving direction 17 in a traffic space 19, for example a road. Objects 20, such as other vehicles, pedestrians, or stationary obstacles, may be located in the traffic space 19.

[0034] The radar system 13 is configured for transmitting at least one primary radar signal 21 into the traffic space 19 and for detecting objects 20 present in the traffic space 19 on the basis of at least one secondary radar signal 22 reflected by the objects 20, as is generally known in the art.

[0035] According to various embodiments, and with reference also to FIGS. 2 and 3, the radar system 13 comprises a radar antenna assembly 25 for transmitting primary radar signals 21 into the traffic space 19 and for receiving secondary radar signals 22 reflected by objects 20 present in the traffic space 19. The radar antenna assembly 25, which is schematically depicted in FIGS. 2 and 3, is integrated in a crash beam 27 of the vehicle 11 (FIG. 1). The crash beam 27, which may be made from steel or another metal, is fixedly connected to a frame or a body of the vehicle 11. For example, the crash beam 27 may be configured as a hollow profile. A front surface 29 of the crash beam 27 comprises a curved surface portion 31 in the form of a depression.

[0036] The radar antenna assembly 25 comprises a feed horn 33 and a reflector 35—i.e., the radar antenna assembly 25 is of the reflector type in some embodiments. As shown, the reflector 35 is formed by the curved surface portion 31 of the crash beam 27. Depending on the application, the curved surface portion 31 may be spherically, parabolically, cylindrically, or elliptically shaped. In the embodiment shown in FIGS. 2 and 3, the feed horn 33 enters the reflector 35 in a central region of the curved surface portion 31. As schematically shown in FIG. 3, the feed horn 33 comprises a plurality of antenna elements 37 pointing to the reflector 35. The antenna elements 37 may be configured as end portions of plastic waveguide members, not shown, which are received in a common conduit 39 and guided, via a passage 36 of the crash beam 27, through the curved surface portion 31. For some applications, a feed horn having a single antenna element 37 may be sufficient.

[0037] The waveguide members are connected to transmitters and/or receivers of a radar circuit (not shown) of the radar system 13. The radar circuit may be configured to generate and process radar signals, as is generally known. For example, the radar circuit may be configured as a monolithic microwave integrated circuit (MMIC). The radar circuit may be arranged in a cavity of the crash beam 27. Thus, only little installation space is required for the radar system 13.

[0038] The crash beam 27 may have a recess and an insert member comprising the curved surface portion 31, wherein the insert member is insertable into the recess. In other words, the reflector 35 may be configured as an insert member. A manufacturer of the radar system 13 may easily prefabricate a module comprising the reflector 35 and deliver the module to a manufacturer of the vehicle 11, who inserts the reflector 35 into the recess of the crash beam 27.

[0039] FIG. 4 shows a radar antenna assembly 25′ according to another embodiment. The depicted radar antenna assembly 25′ has an offset reflector configuration. As shown, the feed horn 33′ is located outside the curved surface portion 31. Due to the illumination of the reflector 35 from the side, the connection of the feed horn 33′ to the corresponding control board is simplified. The offset reflector configuration provides for an improved sidelobe suppression and for an increased polarization purity.

[0040] Apart from the configurations shown in FIGS. 2-4, the feed horn 33, 33′ may enter the reflector 35 at other positions to adapt the side lobe suppression and the polarization purity as desired. Moreover, instead of a curved surface portion 31 as shown in FIGS. 2-4, a faceted portion of the crash beam 27 may form the reflector 35.

[0041] The feed horn 33, 33′ may be operated in a frequency scanning mode to provide a large beam steering range with only one transmitter. Further beam steering capabilities may be achieved by operating a feed horn 33, 33′ comprising several transmitters in a phased array mode. A combination of a frequency scanning and a phased array scanning provides a particularly large beam steering range. The disclosed radar system 13 may exhibit an antenna gain value of approximately 40 decibels relative to an isotropic antenna (dBi). In combination with a circulator at the input port of the reflector 35, a signal to noise ratio of approximately 60 decibels (dB) may be achieved.

[0042] Instead of the curved surface portion 31 of the crash beam 27, a curved surface portion of another existing body or frame structure of the vehicle 11 may be used as a reflector 35. Thus, the curved surface portion 31 may be, for example, a portion of an A-pillar, a bumper, or a door of the vehicle 11.

[0043] The use of an existing metallic structure of a vehicle 11 as a reflector 35 of a radar antenna assembly 25, 25′ is possible in connection with a wide variety of antenna types, for example bistatic, grouped, and multiple input multiple output antennas.

Example Implementations

[0044] Example 1: Radar antenna assembly for a vehicle, the radar antenna assembly comprising: a feed horn configured to transmit and/or receive radar signals; and a metallic component of the vehicle, wherein the metallic component of the vehicle comprises a curved or faceted surface portion, and the feed horn is positioned such that the curved or faceted surface portion forms a reflector for the feed horn.

[0045] Example 2: The radar antenna assembly of example 1, wherein the metallic component forms at least a part of a crash beam, a bumper, a pillar, or a door of the vehicle.

[0046] Example 3: The radar antenna assembly of example 1 or example 2, wherein the feed horn is fixed to the metallic component of the vehicle.

[0047] Example 4: The radar antenna assembly of at least any one of examples 1 to 3, wherein, in a mounted state of the metallic component of the vehicle, the curved or faceted surface portion faces away from a center of the vehicle.

[0048] Example 5: The radar antenna assembly of at least any one of examples 1 to 4, wherein the curved or faceted surface portion is cylindrically or elliptically shaped.

[0049] Example 6: The radar antenna assembly of at least any one of examples 1 to 5, wherein the feed horn comprises a waveguide member for a connection of the feed horn to a radar circuit, and wherein the metallic component comprises a passage through which the waveguide member is guided.

[0050] Example 7: The radar antenna assembly of example 6, wherein the passage is located in a central region of the curved or faceted surface portion.

[0051] Example 8: The radar antenna assembly of example 6, wherein the passage is located outside the curved or faceted surface portion.

[0052] Example 9: The radar antenna assembly of at least any one of examples 6 to 8, wherein the feed horn comprises a plurality of individual antenna elements and a plurality of waveguide members for respective connections of the antenna elements to the radar circuit.

[0053] Example 10: The radar antenna assembly of example 9, wherein the waveguide members are arranged in a common conduit which is guided through the passage.

[0054] Example 11: The radar antenna assembly of at least one of examples 9 to 10, wherein at least two of the individual antenna elements are connected to separate transmitters of a radar circuit.

[0055] Example 12: The radar antenna assembly of at least any one of examples 1 to 11, wherein the metallic component has a recess and an insert member insertable into the recess, and wherein the insert member comprises the curved or faceted surface portion.

[0056] Example 13: Radar antenna assembly for a vehicle, the radar antenna assembly comprising: a feed horn configured to transmit and/or receive radar signals; and a metallic plate member, wherein the metallic plate member comprises a curved or faceted surface portion, wherein the feed horn is fixed to the metallic plate member such that the curved or faceted surface portion forms a reflector for the feed horn, and wherein the metallic plate member is configured for an insertion in a recess of a metallic component of the vehicle.

[0057] Example 14: Radar system for a vehicle, the radar system comprising the radar antenna assembly of at least any one of examples 1 to 13 and a radar circuit for generating and/or processing radar signals, wherein the radar circuit is configured for a multiplex operation, a multiple input multiple output (MIMO) operation, and/or a frequency scan operation of the radar antenna assembly.

[0058] Example 15: Vehicle comprising a chassis, a body, and a radar system comprising the radar antenna assembly of at least any one of examples 1 to 13, wherein the metallic component is a portion of the chassis or the body.

LIST OF REFERENCE CHARACTERS FOR THE ELEMENTS IN THE DRAWINGS

[0059] The following is a list of certain items in the drawings, in numerical order. Items not listed in the list may nonetheless be part of a given embodiment. For better legibility of the text, a given reference character may be recited near some, but not all, recitations of the referenced item in the text. Further, the same reference number may be used with reference to different examples or different instances of a given item. [0060] 11 vehicle [0061] 13 radar system [0062] 15 electronic processing device [0063] 17 driving direction [0064] 19 traffic space [0065] 20 object [0066] 21 primary radar signal [0067] 22 secondary radar signal [0068] 25, 25′ radar antenna assembly [0069] 27 crash beam [0070] 29 front surface [0071] 31 curved surface portion [0072] 33, 33′ feed horn [0073] 35 reflector [0074] 36 passage [0075] 37 antenna element [0076] 39 conduit