A 94 GHz imaging radar system

This report describes the 94 GHz imaging radar system that has been developed and used within the IR/mm project during the years 2001-2003. The new system, which is based on active gate mixers (GaAs MMIC), shows higher performance than an earlier used system, which was based on resistive mixers (InP HEMT). The conversion loss and pumping power requirement have both been reduced which has resulted in a significant improvement of the system sensitivity. A measured SNR of about 3 dB has been obtained (in average over 4x8 channels) for a 1 m2 target at a 500 m measurement distance.