Interferometric sounding using a Compressive Reflector Antenna

Abstract

This paper presents a novel interferometric system for sensing the physical temperature radiated from the Earth. The proposed system consists of a Compressive Reflector Antenna (CRA) using a Y-shaped receiving array. The Compressive Reflector Antenna creates a spatial codification in the far-field of the antenna; or, by using the reciprocity theorem, it creates spatial codes in the focal plane array region when it is operating in reception mode. The sensing matrix of the system is generated by using a high frequency method based on Physical Optics, and its inversion is performed using Compressive Sensing techniques. Numerical results demonstrate the effectiveness of the proposed system for reconstructing a typical map of the physical temperature of the Earth. The proposed CRA provides similar imaging performance as that of a current state of the art system GeoSTAR; however, the former only needs one half of the horns used by the latter.

Compressive Reflector Antenna Phased Array

“…A metamaterial absorber (MMA) [4,5,[13][14][15] , which was originally introduced by Landy et al [15], poses a unique behavior that can be exploited for sensing and imaging applications. Specifically, by using an array of MMAs, in which each element of the array presents a nearunity absorption at a specified frequency, one can produce codes that are changed with the instantaneous frequency of the radar chirp, as presented in Ref.…”

“…Recently, a new beamforming technique based on a compressive reflector antenna (CRA) was proposed [1][2][3][4][5][6] to improve the sensing capacity of an active sensing system. This improvement has enhanced the information transfer efficiency from the sensing system to the imaging domain and vice versa.…”

“…This unique feature of CRAs has triggered its use in a wide variety of applications, which include the following: (a) active imaging of metallic targets at mm-wave frequencies [1][2][3], (b) passive imaging of the physical temperature of the Earth at mm-wave frequencies [4,5], and (c) active imaging of red blood cells at optical frequencies [6].…”

Enhancing Millimeter-Wave Computational Interferometric Imaging

“…To overcome these limitations, computational techniques were implemented to reduce the number of active chains required for interferometric imaging systems by adding various types of components for encoding signals into the physical layer quoting code-modulated arrays [16], frequency dispersive reflectarray antennas [17], dynamic metasurfaces [18] and electrically large metallic multiplexing cavities [19]- [23]. The latter is based on the use of passive coding devices initially developed in the microwave domain and then adapted to the millimeter wave range [24]- [26].…”

A Gpu Implementation of the Inverse Fast Multipole Method for Multi-Bistatic Imaging Applications

“…Parallelization using GPUs is desired for the IFMM algorithm given that it can be used as an image reconstruction algorithm in a mm-wave concealed threat detection system. Solving this problem and generating real-time images is extremely important for a deployable system, including those operating in high-capacity mode [15][16][17][18][19][20]. The Department of Homeland Security (DHS), through its mission of preventing terrorism and enhancing security, requires a high throughput, non-invasive, accurate, and quick detection of person-borne threats in highly secure areas [1-3, 5, 6].…”