Avalanche diode harmonic optoelectronic mixer

The paper describes the use of an avalanche diode to provide the combined functions of optical detection and harmonic electrical mixing. A simple analytic theory of avalanche optoelectronic mixer operation is presented and used to evaluate the conversion loss and noise performance of the mixer. The theoretical predictions are compared with experimental measurements of harmonic optoelectronic mixing up to the fifth harmonic. Measured conversion losses relative to direct optical detection ranged from 3 dB for fundamental mixing to IS dB for fifth-harmonic mixing. Frequency response limitations are briefly discussed.