Fundamental low phase noise InP-based DHBT VCOs with high output power operating up to 75 GHz

Fundamental low phase noise MMIC VCOs with high output power using InP/InGaAs double heterostructure bipolar transistors (DHBTs) are reported. A first VCO with output buffer has been designed for +70 GHz operation and exhibits oscillation frequencies ranging from 70.9 GHz to 75 GHz. At 74 GHz, the VCO features a minimum phase noise of -97 dBc/Hz at 1 MHz offset frequency. Within the tuning range, a single ended output power up to 8 dBm was measured, resulting in a total signal power of 11 dBm. The second VCO version without output buffer was targeted for the 44 GHz range. The achieved operation frequencies range from 43.4 GHz to 48 GHz, with up to 2 dBm single-ended output power. At 48 GHz, a minimum phase noise of -102 dBc/Hz at 1 MHz offset frequency is achieved.