The study and application of D-band radiometer front-end

A D-band(110~170 GHz) direct detection radiometer front-end which consists of detector module, low noise amplifier module and standard gain horn antenna. The D-band detector is designed and fabricated based on zero-bias Schottky barrier diode HSCH-9161 and the measurement shows that the voltage sensitivity is larger than 400 mV/mW between 110~140 GHz, larger than 120 mV/mW in D-band and the maximal value reaches about 1 600 mV/mW@110 GHz. The D-band LNA module is packaged with self-designed MMIC and the module measurement shows the peak gain is 10.8 dB@139 GHz, the gain higher than 7.8 dB from 137 GHz to 144 GHz, the measured input return loss (S11) and output return loss (S22) are better than -5 dB and 8.5 dB in operating frequencies, respectively. Finally, the imaging experiments based on this front-end are carried out.