Imaging Systems and Associated Methods

Patent metadata

Field	Value
Publication number	US-2024118411-A1
Application number	US-202217959890-A
Country	US
Kind code	A1
Filing date	Oct 4, 2022
Priority date	Oct 4, 2022
Publication date	Apr 11, 2024
Grant date	—

Abstract

Imaging systems and associated methods are described. According to one aspect, an imaging system includes an antenna array having transmit and receive antennas, the transmit antennas emit electromagnetic energy from a plurality of different positions about a target imaging volume and the receive antennas receive reflections of the electromagnetic energy at the different positions, a transceiver configured to control the emission of the electromagnetic energy and to generate radar data that is indicative of the reflections of the electromagnetic energy received via the receive antennas; and processing circuitry configured to focus the radar data to provide first focused data in a first dimension, to focus the radar data in a second dimension to provide second focused data, and use the second focused data to focus the radar data in a third dimension to provide third focused data comprising an image of the target imaging volume.

First claim

What is claimed is:

1 . An imaging system comprising:
an antenna array comprising a plurality of transmit antennas and a plurality of receive antennas that are arranged along an at least substantially straight axis; wherein the transmit antennas are configured to emit electromagnetic towards a target imaging volume and the receive antennas are configured to receive reflections of the electromagnetic energy from the target imaging volume; wherein the transmit antennas and the receive antennas are located at a plurality of different positions along a scan path at different moments in time during the emission and reception of the electromagnetic energy; a transceiver coupled with the antenna array, wherein the transceiver is configured to control the emission of the electromagnetic energy from the transmit antennas and to generate radar data that is indicative of the reflections of the electromagnetic energy received via the receive antennas; and processing circuitry configured to:
focus the radar data to provide first focused data in a first dimension of the target imaging volume;
use the first focused data to focus the radar data in a second dimension of the target imaging volume to provide second focused data; and
use the second focused data to focus the radar data in a third dimension of the target imaging volume to provide third focused data comprising an image of the target imaging volume.

2 . The system of claim 1 wherein the first dimension is a range dimension of the target imaging volume.

3 . The system of claim 2 wherein the at least substantially straight axis of the antenna array defines a first dimension of an imaging aperture, the different positions of the transmit and receive antennas define a second dimension of the imaging aperture, a plurality of pairs of transmit and receive antennas define a plurality of different aperture positions of the imaging aperture along the at least substantially straight axis and at the different positions of the transmit and receive antennas, and the processing circuitry is configured to provide the first focused data for each of the aperture positions of the imaging aperture.

4 . The system of claim 1 wherein the second dimension is a vertical dimension of the target imaging volume.

5 . The system of claim 4 wherein the processing circuitry is configured to provide the second focused data comprising a plurality of intermediate response values for a plurality of locations of the target imaging volume.

6 . The system of claim 5 wherein the locations of the target imaging volume correspond to locations of different cylindrical radii and different cylindrical elevations at the different positions of the transmit and receive antennas.

7 . The system of claim 1 wherein the third dimension is a lateral dimension of the target imaging volume.

8 . The system of claim 7 wherein the processing circuitry is configured to provide the third focused data comprising a plurality of final response values for a plurality of voxels of the target imaging volume.

9 . The system of claim 1 further comprising storage circuitry configured to store the second focused data comprising intermediate response values in a plurality of look up tables corresponding to the different positions of the transmit and receive antennas, wherein the processing circuitry is configured to provide the third focused data comprising a plurality of final response values for a plurality of voxels of the target imaging volume and wherein the processing circuitry is configured to use one of the intermediate response values from each of the look up tables to provide one of the final response values.

10 . The system of claim 9 wherein the processing circuitry is configured to, for each of the voxels, identify a plurality of cylindrical radii and a plurality of cylindrical elevations, and to use the cylindrical radii and the cylindrical elevations to identify the intermediate response values from the look up tables.

11 . The system of claim 1 further comprising a user interface configured to display images, and wherein the processing circuitry is configured to use the third focused data to display an image of the target imaging volume.

12 . The system of claim 1 wherein the processing circuitry is configured to demodulate the first focused data to remove fast phase variations prior to focusing of the radar data in the second dimension.

13 . The system of claim 1 wherein the processing circuitry is configured to demodulate the second focused data to remove fast phase variations prior to the focusing of the radar data in the third dimension.

14 . The system of claim 1 wherein the antenna array is configured to move to provide the transmit and receive antennas at the different positions.

15 . The system of claim 1 wherein the antenna array comprises a plurality of antenna sub-arrays comprising the transmit and receive antennas at the different positions.

16 . An imaging system comprising:
an antenna array comprising a plurality of transmit antennas and a plurality of receive antennas that are arranged along an at least substantially straight axis; wherein the transmit antennas are configured to emit electromagnetic towards a target imaging volume and the receive antennas are configured to receive reflections of the electromagnetic energy from the target imaging volume; wherein the transmit antennas and the receive antennas are located at a plurality of different positions along a scan path at different moments in time during the emission and reception of the electromagnetic energy; a transceiver coupled with the antenna array, wherein the transceiver is configured to control the emission of the electromagnetic energy from the transmit antennas and to generate radar data that is indicative of the reflections of the electromagnetic energy received via the receive antennas; and processing circuitry configured to:
convert frequency data within the radar data to range data;
for each of the different positions of the transmit and receive antennas, use the range data to determine a plurality of intermediate response values for a plurality of locations of the target imaging volume; and
for each of a plurality of voxels of the target imaging volume, use a location of the respective voxel to identify one of the intermediate response values for each of the different positions of the transmit and receive antennas and use the identified response values to determine a final response value for the respective voxel; and
wherein the final response values for the voxels comprise an image of the target imaging volume.

17 . The system of claim 16 wherein the at least substantially straight axis of the antenna array defines a first dimension of an imaging aperture, the different positions of the transmit and receive antennas define a second dimension of the imaging aperture, a plurality of pairs of transmit and receive antennas define a plurality of different aperture positions of the imaging aperture along the at least substantially straight axis and at the different positions of the transmit and receive antennas, and the processing circuitry is configured to provide the range data for each of the aperture positions of the imaging aperture.

18 . The system of claim 16 wherein the use of the range data to determine the intermediate response values focuses the radar data in a vertical dimension of the target imaging volume.

19 . The system of claim 16 wherein the locations of the target imaging volume cor

Assignees

• Battelle Memorial Institute

Inventors

• Sheen David M
• Clark Richard Trevor

Classifications

• G01S13/887 Primary

  for detection of concealed objects, e.g. contraband or weapons · CPC title

• G01S7/043

  Synchronising the display device with the scanning of the antenna · CPC title

• G01S7/06

  Cathode-ray tube displays {or other two dimensional or three-dimensional displays} · CPC title

• G01S13/9019

  Auto-focussing of the SAR signals · CPC title

• G01V3/12 Primary

  operating with electromagnetic waves {(operating with millimetre waves G01V8/005)} · CPC title