Design of a coherent polarimetric 1.56 THz receiver for three-dimensional radar imaging of scaled model targets.

摘要

This dissertation describes the modification of an existing V-polarization (V-pol) coherent transmit/receive submillimeter-wave laser radar transceiver to allow the reception of the H-polarization state in addition to the existing V-pol capability. This frequency agile polarimetric superheterodyne (i.e. phase sensitive) system operates by scanning a small focused beam of radiation across a target to resolve target scattering centers. The resulting locations of scattering centers are presented in three dimensions. Targets are scaled in size relative to the wavelength of the transmitted radiation to provide the RCS of a full-size target at millimeter wavelengths. Since the 3DI system operates in the submillimeter wavelength regime, the related system design incorporates both optical and microwave design techniques. Amplitude, polarization, and phase calibration routines are also applied to this system. Upon examining the results of a number of actual data runs the H-pol receiver channel is found to operate within predicted specifications.