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EP-4274027-B1 - WAVEGUIDE WITH SLOT ANTENNAS AND REFLECTORS

EP4274027B1EP 4274027 B1EP4274027 B1EP 4274027B1EP-4274027-B1

Inventors

  • Gupta, Biswadeep Das
  • SAQUEB, SYED AN NAZMUS
  • BRANDENBURG, SCOTT D.
  • ZIMMERMAN, DAVID WAYNE
  • WHITHAUS, WARREN

Dates

Publication Date
20260513
Application Date
20230228

Claims (11)

  1. A system (102) comprising: an antenna element; a device configured to transmit or receive electromagnetic signals via the antenna element (204), the device comprising: a plurality of waveguide channels (112), each waveguide channel including a hollow channel for a dielectric, the hollow channel including a plurality of slot antennas (114), each of the slot antennas (114) comprising an opening through a surface of the waveguide channel (112) that defines the hollow channel, each of the slot antennas (114) being operably connected with the dielectric; and a plurality of reflectors (116), the plurality of reflectors being positioned adjacent to and offset from each longitudinal side of each waveguide channel (112), the plurality of reflectors (116) and the plurality of waveguide channels (112) being arranged to produce a particular radiation pattern for the antenna element (204) that is electrically coupled to the dielectric from a floor of the hollow channel of each waveguide channel (112), characterized in that the plurality of reflectors (116) consists of a first single structure (906); and the plurality of waveguide channels (112) consists of a second single structure (908).
  2. The system of claim 1, wherein the plurality of reflectors (116) are not part of a ground plane of the waveguide channel (112).
  3. The system of claim 1 or 2, wherein the plurality of reflectors (116) are offset an equal distance from each longitudinal side of the waveguide channel (112).
  4. The system of claim 1 or 2, wherein: a first reflector of the plurality of reflectors (116) is offset a first distance from a first longitudinal side of the waveguide channel (112); and a second reflector of the plurality of reflectors (116) is offset a second distance from a second longitudinal side of the waveguide channel (112), the second distance not being equal to the first distance.
  5. The system of claim 4, wherein the second distance is at least three times larger than the first distance.
  6. The system of any one of the preceding claims, wherein the reflectors (116) each have a height that is greater than a height of the waveguide channel (112).
  7. The system of any one of the preceding claims, wherein: the hollow channel forms an approximately rectangular shape along a longitudinal direction (208) of the waveguide channel (112); each slot antenna (114) of the plurality of slot antennas is offset a non-uniform distance from a centerline of the hollow channel, the centerline being parallel with the longitudinal direction (208) of the waveguide channel (112); and the plurality of slot antennas (114) is evenly distributed along the longitudinal direction (208).
  8. The system of any one of the preceding claims, wherein a floor of the hollow channel is formed by a printed circuit board, PCB.
  9. The system of any one of the preceding claims, wherein the reflectors (116) have an approximately rectangular shape.
  10. A method comprising: forming a plurality of waveguide channels (112), each waveguide channel including a hollow channel for a dielectric, the hollow channel including a plurality of slot antennas (114), each of the slot antennas comprising an opening through a surface of the waveguide channel (112) that defines the hollow channel, each of the slot antennas (114) being operably connected with the dielectric; forming a plurality of reflectors (116); and assembling the plurality of waveguide channels (112) and the plurality of reflectors (116) onto a printed circuit board, PCB, to form a device configured to transmit or receive electromagnetic signals via an antenna element, the plurality of reflectors (116) being positioned adjacent to and offset from each longitudinal side of each waveguide channel (112), the plurality of reflectors (116) and the plurality of waveguide channels (112) being arranged to produce a particular radiation pattern for the antenna element that is electrically coupled to the dielectric from a floor of the hollow channel of each waveguide channel (112), wherein: each waveguide channel (112) is formed by stamping a metal sheet and assembled onto the PCB using solder; and the plurality of reflectors (116) consists of a single structure (706, 906) that is attached or held in place to the PCB using at least one of screws, adhesive, or a radome structure, the single structure comprising a molded or three-dimensionally printed material, the material comprising at least one of aluminum, plated plastic, or conductive plastic.
  11. The method of claim 10, wherein: the plurality of waveguide channels (112) comprises a first single structure (908) the single structure of the plurality of reflectors is a second single structure (906); and the first single structure (908) and the second single structure (906) comprise hydroformed metal plates.

Description

BACKGROUND Some devices (e.g., radar systems) use electromagnetic signals to detect and track objects. The electromagnetic signals are transmitted and received using one or more antennas. The radiation pattern of an antenna may be characterized by gain or beamwidth, which indicates gain as a function of direction. Precisely controlling the radiation pattern can improve the application of a radar system. For example, many automotive applications require radar systems that provide a wide beamwidth to detect objects within a particular field of view (e.g., in a travel path of the vehicle). Other automotive applications require an asymmetrical beamwidth to detect objects within a different field of view. A waveguide may be used to improve and control the radiation pattern of either type of device. Such waveguides can include perforations or radiating slots to guide radiation near the antenna due to their ease of design and relatively wide field of view. These slot antennas often require large ground plans to achieve a wide field of view. In the absence of a large ground plane, slot antennas can have a smaller field of view with ripples in the radiation pattern. In addition, arrays of slot antennas are susceptible to coupling among adjacent antenna elements and edge firing that negatively impacts phase monotonicity. AULIA DEWANTARI ET AL: "Flared SIW antenna design and transceiving experiments for W-band SAR", INTL JOURNAL OF RF AND MICROW. CAE, WILEY, vol. 28, no. 9, 9 May 2018, pp. 1-9, XP072009558, ISSN: 1096-4290, DOI: 10.1002/MMCE.21416 discloses a system according to the preamble of claim 1. EP 0 174 579 A2 discloses a shaped beam antenna. SUMMARY The invention is defined by the independent claims. This document describes techniques, apparatuses, and systems for a waveguide with slot antennas and reflectors. An apparatus includes a waveguide channel that includes a hollow channel containing a dielectric and an array of slot antennas through a surface that is operably connected with the dielectric. The apparatus also includes reflectors positioned adjacent to and offset from each longitudinal side of the waveguide channel. The reflectors and the waveguide channel are positioned to generate a particular radiation pattern for an antenna element electrically coupled to the dielectric. In this way, the described waveguide with slot antennas and reflectors can adjust the positioning of the reflectors to provide a radiation pattern with a wide or asymmetric beamwidth. This document also describes methods performed by the above-summarized techniques, apparatuses, and systems, and other methods set forth herein, as well as means for performing these methods. This Summary introduces simplified concepts related to a waveguide with slot antennas and reflectors, further described in the Detailed Description and Drawings. This Summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS The details of one or more aspects of a waveguide with slot antennas and reflectors are described in this document with reference to the following figures. The same numbers are often used throughout the drawings to reference like features and components: FIG. 1 illustrates an example environment in which a radar system with a waveguide with slot antennas and reflectors assembly is used on a vehicle;FIG. 2 illustrates a top view of a waveguide with slot antennas and reflectors;FIG. 3 illustrates a side view of a waveguide with slot antennas and reflectors;FIG. 4 illustrates example radiation patterns associated with a waveguide without and with reflectors;FIGs. 5 and 6 illustrate a top view and side view of a waveguide with slot antennas and asymmetrically spaced reflectors;FIGs. 7A and 7B illustrate a perspective view and an exploded view of an example array of waveguides with slot antennas and reflectors;FIG. 8 illustrates example radiation patterns associated with an example array of waveguides with slot antennas and reflectors;FIGs. 9A and 9B illustrate a perspective view and an exploded view of another example array of waveguides with slot antennas and reflectors; andFIG. 10 illustrates an example method for manufacturing a waveguide with slot antennas and reflectors following techniques, apparatuses, and systems of this disclosure. DETAILED DESCRIPTION OVERVIEW Radar systems are a sensing technology that some automotive systems rely on to acquire information about the surrounding environment. Radar systems generally use an antenna to direct electromagnetic energy or signals being transmitted or received. Such radar systems can use multiple antenna elements (e.g., slot antennas) in an array to provide increased gain and directivity in comparison to the radiation pattern achievable with a single antenna element. Signals from the multiple antenna elements are combined with appropriate phases and