3D folded compact beam forming network using short wall couplers for automotive radars

Patent metadata

Field	Value
Publication number	US-10276944-B1
Application number	US-201514977957-A
Country	US
Kind code	B1
Filing date	Dec 22, 2015
Priority date	Dec 22, 2015
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

A radar system includes a plurality of radiating elements configured to radiate electromagnetic energy and a plurality of feed waveguides defining a common plane and configured to guide electromagnetic energy to the plurality of radiating elements. The radar system also includes a plurality of waveguides arranged as a dividing network, where the dividing network includes one or more coupling apertures located in the common plane. The dividing network is configured to receive electromagnetic energy from a source and split the electromagnetic energy among the plurality of feed waveguides, such that each feed waveguide receives a respective portion of the electromagnetic energy. The splitting and adjusting of the radar system are based in part on the one or more coupling apertures in the dividing network.

First claim

What is claimed is:

1. A radar system comprising:
a plurality of radiating elements, wherein the radiating elements:
are configured to radiate electromagnetic energy, and
each comprise an open-ended waveguide coupled to a feed waveguide;

a plurality of separate feed waveguides, wherein each feed waveguide is configured to guide electromagnetic energy to at least one of the plurality of radiating elements such that each radiating element corresponds to one of the plurality of feed waveguides, and wherein the plurality of feed waveguides is arranged such that centers of the heights of the feed waveguides are located in a common plane;
a split-block construction, wherein a seam of the split-block defines a common plane; and
a plurality of waveguides arranged as a dividing network, wherein the dividing network includes one or more coupling apertures between respective waveguides in the plurality of waveguides, wherein the dividing network of waveguides includes at least one waveguide having an edge located at a seam of the split-block, wherein the one or more coupling apertures are located in the common plane, wherein the dividing network:
receives electromagnetic energy from a source,
splits the electromagnetic energy from the source among the plurality of feed waveguides, such that each feed waveguide receives a respective portion of the electromagnetic energy from the source,
adjusts a phase of the electromagnetic energy received by each waveguide,
includes a ramp section that couples a section of waveguide that is not in the common plane of the feed waveguides into the common plane of the feed waveguides, and
wherein the splitting and adjusting are based in part on the one or more coupling apertures in the dividing network.

2. The radar system according to claim 1 , wherein the dividing network is coupled to at least one absorption load element.

3. The radar system according to claim 1 , wherein the at least one absorption load element is located on a circuit board.

4. The radar system according to claim 1 , wherein the seam of the split-block is at the center of the height of the feed waveguides.

5. The radar system according to claim 4 , wherein the split-block construction comprises a top half and a bottom half.

6. The radar system according to claim 5 , wherein the split-block construction comprises a top half and a bottom half, and wherein the dividing network of waveguides includes at least one waveguide having an edge located at the coupling aperture.

7. The radar system according to claim 5 , wherein the dividing network of waveguides includes at least two waveguides having an edge located at a seam of the split-block, wherein the edge of each respective waveguide is adjacent to the edge of the other waveguide.

8. The radar system according to claim 5 , wherein the dividing network of waveguides has a non-linear folded layout.

9. The radar system according to claim 7 , further comprising a transition in which at least two waveguides having an edge located at a seam of the split-block converge to a single waveguide centered at the seam.

10. The radar system according to claim 1 , wherein the plurality of feed waveguides has an associated taper profile.

11. The radar system according to claim 10 , wherein the dividing network is configured to split the electromagnetic energy from the source based on the taper profile.

12. A method of radiating a radar signal comprising:
receiving electromagnetic energy from a source;
splitting the electromagnetic energy from the source as a divided signal among a plurality of separate feed waveguides by a dividing network, such that each feed waveguide receives a respective portion of the electromagnetic energy from the source, wherein the dividing network of waveguides includes at least one waveguide having an edge located at a seam of the split-block, and wherein the at least one waveguide having an edge located at a seam of the split-block couples to the feed waveguide by a ramp section;
for each of the plurality of feed waveguides, adjusting a phase of the electromagnetic energy received by each feed waveguide by the dividing network;
for each of the plurality of feed waveguides, coupling electromagnetic energy to a plurality of radiating elements coupled to the feed waveguide; and
radiating electromagnetic energy by the plurality of radiating elements coupled to the plurality of feed waveguides, wherein each radiating element comprises an open-ended waveguide;
wherein the splitting and adjusting are based in part on the one or more coupling apertures in the dividing network, and
wherein the one or more coupling apertures are located in a common plane, wherein the common plane is defined by a seam of a split-block construction.

13. The method according to claim 12 , further comprising absorbing at least a portion of the electromagnetic energy that is not radiated by at least one absorption load element.

14. The method according to claim 12 , wherein the at least one absorption load element is disposed on a circuit board.

15. The method according to claim 12 , wherein the split-block construction comprises a top half and a bottom half, and wherein at least one waveguide has an edge located at a seam of the split-block.

16. The method according to claim 15 , further comprising wherein the dividing network of waveguides includes at least two waveguides having an edge located at a seam of the split-block, wherein the edge of each respective waveguide is adjacent to the edge of the other waveguide.

17. The method according to claim 15 , further comprising transitioning the at least two waveguides having an edge located at a seam of the split-block to a single waveguide centered at the seam.

18. A waveguide system comprising:
a plurality of separate feed waveguides having a center located in a common plane, each feed waveguide configured to conduct electromagnetic energy from an end of the feed waveguide to at least one radiating element coupled to the feed waveguide, wherein a seam of a split-block defines a common plane;
a waveguide source;
at least one coupling aperture located in the common plane, wherein each coupling aperture forms a portion of hybrid coupler;
a dividing network comprising a plurality of waveguides, wherein at least a portion of the dividing network is located in a plane other than the common plane, wherein the dividing network of waveguides includes at least one waveguide having an edge located at the seam of the split-block, wherein the dividing network is configured to:
receive electromagnetic energy from the source,
split the electromagnetic energy from the source among the plurality of feed waveguides, such that each feed waveguide receives an approximately equal respective portion of the electromagnetic energy from the source,
adjust a phase of the electromagnetic energy received by each feed waveguide, and
wherein the splitting and adjusting are based in part on one or more coupling apertures in the dividing network, located in the common plane; and
a ramp section that couples a section of waveguide that is not in the common plane of the feed waveguides into the common plane of the feed waveguides.

Assignees

• Waymo Llc

Inventors

• Izadian Jamal

Classifications

• H01Q21/0037 Primary

  linear waveguide fed arrays · CPC title

• H01Q21/068

  using parallel coplanar travelling wave or leaky wave aerial units (H01Q21/065 takes precedence) · CPC title

• H01Q1/3233

  particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems · CPC title