Ultra‐wideband imaging with an improved backward projection algorithm for far‐field applications

Abstract

Ultra‐wideband (UWB) radar imaging is widely used in penetration detection, target location and detection, and vital monitoring because of its high interference immunity and excellent target recognition with high resolution. In this paper, we report the design of a UWB stepper radar imaging system by using a vector network analyzer and a specially designed novel Vivaldi antenna for far‐field imaging applications. An anti‐attenuation backward projection (AA‐BP) algorithm is proposed to alleviate the attenuation impact of electromagnetic wave propagation. The AA‐BP algorithm and the specially designed Vivaldi antenna are jointly applied in our experiments on multiple targets through wall imaging in both free space and multiple‐path propagation environments. The experimental results show that our reported imaging system achieves desirable performances of far‐field imaging.

Inline Inspection of Packaged Food Using Microwave/Terahertz Sensing—An Overview with Focus on Confectionery Products

“…While the near-field imaging allows a high angular resolution for multistatic radar sensing by using the spatial diversity of the transmit and receive antennas, far-field imaging sets challenging requirements, especially for the hardware design, mainly due to the diffraction limit [12][13][14]. This also applies to the transmit power, too, which decreases with the square of the distance, and also requires lens with case-specific properties, which are required to influence the radiation pattern in order to establish focused propagating waves for sensitivity.…”