Imaging using frequency-scanned radar

Abstract

Antennas oriented at a first orientation toward an area of interest can transform radar signals through a first transformation that physically maps the plurality of radar signals with a plurality of unique beam angles corresponding to a plurality of unique frequencies. Antennas oriented at a second orientation toward the area of interest can transform radar signals through a second transformation completing the first transformation. A frequency scan can be performed on a first plurality of responses to first radar signals to identify first spatial data along a first dimension. Second spatial data at second spatial location along a second dimension can be created from a second plurality of responses corresponding to the second transformation. An image can be generated using the first spatial data and the second spatial data while a range value of the area of interest can be determined using the first plurality of responses.

1 . A radar imaging system comprising:
 an antenna comprising a plurality of antenna elements oriented through a channel toward an area of interest wherein the plurality of antenna elements are configured to transform a representation of one or more radar signals;   one or more signal processing modules operative to use the transformation of the representation of the one or more radar signals to generate one or more measurements for the area of interest;   an image formation module operative to form a plurality of voxels of the area of interest using the one or more measurements and to generate images of the field of view using the plurality of voxels, thereby imaging the field of interest using the one or more radar signals.   
     
     
         2 . The radar imaging system of  claim 1 , wherein the antenna elements comprise a plurality of Multiple Input Multiple Output (MIMO) antenna elements. 
     
     
         3 . The radar imaging system of  claim 1 , wherein:
 the antenna elements comprise a plurality of Multiple Input Multiple Output (MIMO) antenna elements;   the MIMO antenna elements are operative to form a virtual array supporting a plurality of spatial channels, wherein the virtual array comprises an element for each of the plurality of spatial channels.   
     
     
         4 . The radar imaging system of  claim 1 , wherein:
 the antenna elements comprise a plurality of Multiple Input Multiple Output (MIMO) antenna elements;   the MIMO antenna elements are operative to form a virtual array supporting a plurality of spatial channels, wherein the virtual array comprises an element for each of the plurality of spatial channels, wherein the image formation module is operative to image one or more moving targets within the field of view.   
     
     
         5 . The radar imaging system of  claim 1 , wherein the radar imaging system is mounted on a moving platform. 
     
     
         6 . The radar imaging system of  claim 1 , wherein the radar imaging system is mounted on a ground vehicle or an airborne vehicle. 
     
     
         7 . The radar imaging system of  claim 1 , wherein the radar imaging system is operative to image one or more moving targets within the field of view. 
     
     
         8 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the one or more measurements comprise first measurement parameters for the area of interest in a downrange direction using the phase information, second measurement parameters for the area of interest in a first cross-range direction orthogonal to the downrange direction using the phase information, third measurement parameters for the area of interest in a second cross-range direction orthogonal to the first cross-range direction and the downrange direction using the transmitted bandwidth information, or some combination thereof.   
     
     
         9 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the one or more measurements have one or more measurement resolutions for the field of view.   
     
     
         10 . The radar imaging system of  claim 1 , wherein the plurality of antenna elements are oriented in the downrange direction. 
     
     
         11 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the transmitted bandwidth information corresponds to a bandwidth associated with a narrow band frequency range.   
     
     
         12 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the transmitted bandwidth information corresponds to a bandwidth associated with a narrow band frequency range;   the narrow band frequency range comprises an applicable frequency range for transmitting the one or more radar signals while reducing one or more effects of smearing or beam degradation.   
     
     
         13 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the transmitted bandwidth information corresponds to a bandwidth to increase resolution of the one or more voxels.   
     
     
         14 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the transmitted bandwidth information corresponds to one or more wide-bandwidth signals.   
     
     
         15 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information;   the transmitted bandwidth information corresponds to one or more wide-bandwidth signals; and   the one or more wide-bandwidth signals comprise one or more chirps, one or more digitally modulated signals, one or more amplitude modulated signals, or some combination thereof.   
     
     
         16 . The radar imaging system of  claim 1 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the transmitted bandwidth information corresponds to a bandwidth to reduce measurement uncertainty of the third measurement parameters.   
     
     
         17 . The radar imaging system of  claim 1 , wherein the images comprise three-dimensional (3D) images of the field of view formed from the one or more voxels. 
     
     
         18 . The radar imaging system of  claim 1 , wherein the image formation module is operative to create a three-dimensional (3D) point cloud of the area of interest of an imaged volume using the one or more voxels. 
     
     
         19 . The radar imaging system of  claim 1 , wherein the image formation module is operative to:
 use first measurement parameters, the second measurement parameters, and the third measurement parameters to estimate properties of the channel; and   produce one or more images of the field of view using estimated properties of the channel.   
     
     
         20 . The radar imaging system of  claim 1 , wherein the image formation module is operative to:
 use first measurement parameters, the second measurement parameters, and the third measurement parameters to estimate properties of the channel; and   produce one or more images of the field of view using estimated properties of the channel.   
     
     
         21 . A method comprising:
 transforming a representation of one or more radar signals using an antenna comprising a plurality of antenna elements oriented toward an area of interest;   using the transformation of the representation of the one or more radar signals to generate one or more measurements for the area of interest; and   forming a plurality of voxels of the area of interest using the one or more measurements and to generate images of the field of view using the plurality of voxels, thereby imaging the field of interest using the one or more radar signals.   
     
     
         22 . The method of  claim 21 , wherein the antenna elements comprise a plurality of Multiple Input Multiple Output (MIMO) antenna elements and the method further comprises using the MIMO antenna elements to form a virtual array supporting a plurality of spatial channels, wherein the virtual array comprises an element for each of the plurality of spatial channels. 
     
     
         23 . The method of  claim 21 , wherein the antenna elements comprise a plurality of Multiple Input Multiple Output (MIMO) antenna elements and the method further comprises:
 using the MIMO antenna elements to form a virtual array supporting a plurality of spatial channels, wherein the virtual array comprises an element for each of the plurality of spatial channels, and   imaging one or more moving targets within the field of view.   
     
     
         24 . The method of  claim 21 , wherein:
 the one or radar signals have phase information and transmitted bandwidth information; and   the one or more measurements comprise first measurement parameters for the area of interest in a downrange direction using the phase information, second measurement parameters for the area of interest in a first cross-range direction orthogonal to the downrange direction using the phase information, third measurement parameters for the area of interest in a second cross-range direction orthogonal to the first cross-range direction and the downrange direction using the transmitted bandwidth information, or some combination thereof.   
     
     
         25 . A radar imaging system comprising:
 an antenna comprising a plurality of Multiple Input Multiple Output (MIMO) antenna elements oriented through a channel toward an area of interest wherein the plurality of MIMO antenna elements are configured to transform a representation of one or more radar signals and are operative to form a virtual array supporting a plurality of spatial channels, wherein the virtual array comprises an element for each of the plurality of spatial channels;   one or more signal processing modules operative to use the transformation of the representation of the one or more radar signals to generate one or more measurements for the area of interest;   an image formation module operative to form a plurality of voxels of the area of interest using the one or more measurements and to generate images of the field of view using the plurality of voxels, wherein the image formation module is operative to image one or more moving targets within the field of view and to image the one or more moving targets within the field of view using the one or more radar signals.   
     
     
         26 . A radar imaging system comprising:
 an antenna comprising a plurality of Multiple Input Multiple Output (MIMO) antenna elements oriented through a channel toward an area of interest wherein the plurality of MIMO antenna elements are configured to transform a representation of one or more radar signals;   
       memory;
 one or more processors coupled to the memory and configured to perform a computer-implemented method comprising: 
 using the MIMO antenna elements to form a virtual array supporting a plurality of spatial channels, wherein the virtual array comprises an element for each of the plurality of spatial channels 
 using the transformation of the representation of the one or more radar signals to generate one or more measurements for the area of interest; and 
 forming a plurality of voxels of the area of interest using the one or more measurements and to generate images of the field of view using the plurality of voxels, wherein the image formation module is operative to image one or more moving targets within the field of view and to image the one or more moving targets within the field of view using the one or more radar signals.