Improved Methods for Fourier-Based Microwave Imaging

Sensors (Basel). 2023 Nov 17;23(22):9250. doi: 10.3390/s23229250.

Abstract

Fourier-based imaging has been widely adopted for microwave imaging thanks to its efficiency in terms of computational complexity without compromising image resolution. Together with other backpropagation imaging algorithms like delay-and-sum (DAS), they are based on a far-field approach to the electromagnetic expression relating to fields and sources. To improve the accuracy of these techniques, this contribution presents a modified version of the well-known Fourier-based algorithm by taking into account the field radiated by the Tx/Rx antennas of the microwave imaging system. The impact on the imaged targets is discussed, providing a quantitative and qualitative analysis. The performance of the proposed method for subsampled microwave imaging scenarios is compared against other well-known aliasing mitigation methods.

Keywords: Fourier-based imaging; antenna measurement; delay-and-sum (DAS); microwave imaging; plane wave spectrum (PWS).