US 12,216,199 B2 · De-aliased imaging for a synthetic aperture radar

Abstract

This document describes techniques for enabling de-aliased imaging for a synthetic aperture radar. Radar signals processed by a synthetic aperture radar (SAR) system may include false detections in the form of aliasing induced by grating lobes. The techniques described herein can reduce the adverse effects of grating lobes by obtaining an initial SAR image using a back-projection algorithm. Aliasing effects (e.g., false detections) in this initial image may be common due to the limitations of an SAR system moving at non-uniform speeds. A refined image is produced from the initial image by applying a de-aliasing filter to the initial image. The refined image may have reduced or eliminated false detections that attribute to aliasing effects, resulting in a better representation of the environment of the vehicle.

Claims17

Dependent claims

A method of de-aliased imaging for a synthetic aperture radar, the method comprising:

identifying, based on multiple frames of signals received by a plurality of receive channels of a radar system, range-Doppler detections corresponding to each receive channel of the plurality of receive channels;
applying a back-projection algorithm to the range-Doppler detections identified for each of the receive channels to determine a set of pixels for each respective receive channel, each pixel in each of the sets of pixels indicative of the range-Doppler detections identified at a position corresponding to that pixel;
deriving, from each set of pixels, initial images related to each receive channel;
applying a de-aliasing filter to the initial images derived from the back-projection algorithm to produce a refined image;
and
outputting, to a system for controlling a vehicle, the refined image produced by the de-aliasing filter applied to the initial images derived from the back-projection algorithm.

3 more elements

A computer-readable storage medium comprising instructions that, when executed, configure at least one processor to:

identify, based on multiple frames of signals received by a plurality of receive channels of a radar system, range-Doppler detections corresponding to each receive channel of the plurality of receive channels;
apply a back-projection algorithm to the range-Doppler detections identified for each of the receive channels to determine a set of pixels for each respective receive channel, each pixel in each of the sets of pixels indicative of the range-Doppler detections identified at a position corresponding to that pixel;
derive, from each set of pixels, initial images related to each receive channel;
apply a de-aliasing filter to the initial images derived from the back-projection algorithm to produce a refined image;
and
output, to a system for controlling a vehicle, the refined image produced by the de-aliasing filter applied to the initial images derived from the back-projection algorithm.

3 more elements

Dependencies are inferred from the claim text.

De-aliased imaging for a synthetic aperture radar

Life of this patent

De-aliased imaging for a synthetic aperture radar

Life of this patent

Abstract

Claims17