Terahertz imaging radar with aperture synthetic techniques for object detection

Terahertz imaging is considered as a promising detection and imaging method with wide application prospect in security inspection and counter-terrorism. In this paper, we present a frequency-modulated continuous-wave (FMCW) imaging radar with phase coherent reception. The proposed radar scheme works at 240GHz with a bandwidth of 4.8GHz. The basic functionality of the radar has been verified experimentally and the results demonstrate that the effective range resolution is better than 4cm, in the condition without the compensation of chirp nonlinearity of the transmitted wave. In addition, to verify the imaging performance of THz radar, an ISAR experiment is performed and the imaging result shows that the imaging radar can achieve high resolution in the range and azimuth dimension.

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