A Microwave Holographic Imaging Method by Photo-induced Plasma Scanning

Based on the newly developed photo-induced plasma-assisted electromagnetic field distribution measurement technique, we present an efficient target imaging method. In our experiments, the transmitter/receiver antenna of the system operates in continuous wave mode under the condition of a single station. The target was placed in front of the antenna and covered by the antenna beam. A silicon wafer was used as an electric field detector, which was placed behind the object. By scanning on the surface of the silicon wafer with a laser, the photoinduced plasma was generated and scattered the electromagnetic wave at different positions on the wafer in turn. The electric field distribution at the silicon wafer position was mapped by recording scattered signals. The holographic images can be obtained by calculating the inverse propagation of the scattered electric field back to the position of the target. The proposed method is efficient and convenient, which can be a new method for microwave detection.