Synthetic Aperture Terahertz Imaging with an Optoelectronic FMCW Radar

We demonstrate synthetic aperture terahertz imaging with an optoelectronic system based on continuous-wave lasers. A frequency-swept optical beat signal generates the terahertz field, which is then coherently detected by photomixing. The system is setup in a monostatic transceiver configuration in connection with a X-Y scanning stage. While the transceiver provides frequency tunability to up to 4 THz, it is operated with a frequency modulation bandwidth of 600 GHz within the lower terahertz regime (< 1 THz) in order to achieve a reasonable dynamic range at high measurement rates, allowing to do imaging with synthetic apertures and in the future real time measurements with MIMO systems