28 and 42 GHz narrow-band InP based phototransistor mixers for hybrid fibre radio distribution systems

The design and characteristics of narrow-band phototransistor mixers operating at 28 and 42 GHz, using an improved phototransistor with optical gain of 98 GHz, are described in this paper. The optoelectronic mixer circuits exhibit a record conversion gain of 12 dB and 9 dB at 28 GHz and 42 GHz, respectively.