Generation of millimetre and sub-millimetre waves by photomixing in 1.55 [micro sign]m wavelength photodiode

A 70 GHz bandwidth commercial photodiode has been used to create a photomixer source of radiation at frequencies from 70 GHz to above 600 GHz. The waveguide source is driven by two 1.55 /spl mu/m lasers and delivers a peak, nonsaturated, power of -7.5 dBm at 110 GHz with a power conversion efficiency above 1%. Detected power decreases approximately as 1/(frequency)/sup 4/ above 150 GHz.