A 37/spl sim/50 GHz InP HBT VCO IC for OC-768 fiber optic communication applications

This paper reports a 50 GHz voltage-controlled-oscillator (VCO) integrated circuit (IC) designed for OC-768 fiber optic communication applications. Implemented with a 140 GHz f/sub t/ InP HBT technology, the VCO IC is designed based on a modified Colpitts configuration with a unique resonator to maximize the tuning range. Tuned by a single-ended voltage, the VCO exhibits 37/spl sim/50 GHz (30%) tuning range over a tuning voltage range of 1.2 V.