Microwave Imaging Using Focused Array Antenna

A novel phased-array solution to two-dimensional microwave imaging is proposed in this paper. Four microstrip antennas are used as transmitters, whereas a near-field focused array antenna is used to harvest the scattered energy by the object under test (OUT), and the image of the OUT can be reconstructed by a combination of SAR algorithm and frequency scan. The proposed setting of the imaging system has two superiorities. First, the beam is focused in the near-field, with low near-field sidelobes, which reduces interruptions. Second, the use of frequency-scanned linear subarrays reduces the cost caused by complex beam-forming network or switching system.

I. Introduction

Microwave imaging is widely used in multiple applications recently, such as breast cancer detection, concealed weapon detection and non-destructive testing. During the years, researchers have explored different solutions to realize qualified imaging reconstruction, among which, the state-of-the-art one is based on synthesized-aperture radar (SAR) algorithm.