Frequency dependent noise in millimeter-wave Schottky barrier diode mixers

The excess noise generated in pumped gallium arsenide Schottky barrier diode mixers has been measured between 40 and 170 GHz, and has been found to increase monotonically with frequency and with L0 power, to values well in excess of T
o
. This noise may be explained by a coherent shot-noise model, although avalanche and intervalley-scattering might contribute a minimal additional noise component.