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arXiv · 2605.03875

Phase-Corrected Near-Field Microwave Imaging via Inverse Source Reconstruction with Modulated Signals

Quanfeng Wang·Alexander H. Paulus·Thomas F. Eibert
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Abstract

An inverse source reconstruction (ISR) based 3-D near-field (NF) passive radar microwave imaging method utilizing modulated signals is presented. The modulated signals from a non-cooperative transmitter are scattered by the targets of interest and captured by a fixed reference antenna together with an NF scanning probe at different positions. By normalizing with the reference signals, spatial coherence of the NF observations is obtained, and a single-frequency inverse source solver is subsequently utilized for ISR and image generation. A corresponding phase correction method is proposed for the coherent superposition of multi-frequency images and verified through simulations. In addition, it is shown that for realistic narrowband signals, an incoherent imaging approach is sufficient. The presented technical scheme is validated using a planar scanning system in a typical office room, where software-defined radios are employed for the transmitting and receiving of narrowband orthogonal frequency-division multiplexing signals at Wi-Fi operating frequencies. With the aid of background subtraction and reference signals, images of a mannequin placed in the office room are successfully obtained.

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Quanfeng Wang, Alexander H. Paulus, Thomas F. Eibert. 2026-05-05. Phase-Corrected Near-Field Microwave Imaging via Inverse Source Reconstruction with Modulated Signals. https://doi.org/10.23919/eucap68105.2026.11612585

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