An experimental 225 GHz pulsed coherent radar

An experimental coherent pulsed radar operating at 225 GHz is described. The system uses a pulsed, phase-locked extended interaction oscillator transmitter and frequency divided by 4 subharmonic mixer pumped by a phase-locked Gunn oscillator as the receiver. A quasi-optical circular polarization duplexer combines transmitter and receiver signals into the same antenna. Results presented include the detection of targets out to ranges of 3.5 km and observations of Doppler spectra of trucks and tracked vehicles which show contributions from both body and tracks.<
>