Ka-band monolithic InGaAs/InP HBT VCO's in CPW structure

Abstract

Two Ka-band monolithic voltage controlled oscillators (VCO's) designed in a coplanar waveguide (CPW) structure are described. Each VCO utilizes an InGaAs/InP heterojunction bipolar transistor (HBT) as the active device and an HBT base-collector junction as the tuning varactor. These two VCO's are biased at a very low voltage of V/sub CE/=1.5 V and the emitter current is less than 10 mA. Under this low dc power dissipation, the VCO's with center frequencies of 26.5 and 33.5 GHz show high dc-to-rf conversion efficiencies over 10% and 5% within the frequency tuning ranges of 1.6 and 1.2 GHz, respectively. The measured phase noise at 1 MHz offset frequency is -110 dBc/Hz.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>