A low noise wideband mixer for 3MM band

A 3mm band cooled low-noise mixer was designed and fabricated for the millimeter wave receiver of the first radioastronomical telescope in China. The mixer noise figure of 3.7 dB, and a conversion loss of 6.4 dB at room temperature is reported. The noise temperature of the mixer at 20K is T/sub M(DSB)/ - 150K; the total noise temperature of the receiver system is T/sub sys(DSB)/ - 232K.