29 GHz E-plane biphase modulator

A biphase PSK modulator for use in 29 GHz radio equipment has been developed that gives state-of-the-art performance (less than 3 dB insertion loss across 7% bandwidth, including transition losses, and 70/100 Mbit/s data rate using PIN diodes as the switching elements). A drive amplifier has been developed for use with the modulator that allows beam lead PIN diodes with a long minority carrier lifetime to be used in the circuit up to 70 Mbit/s.