A low noise heterodyne receiver for astronomical observations operating around 0.63 mm wavelength

A heterodyne receiver is described in which an InSb hot electron bolometer is used as a mixer. The local oscillator power is obtained by doubling the frequency of a backward wave oscillator. The receiver operates between 460 and 500 GHz (0.65–0.6 mm). Noise temperatures amount typically to 1000 K.