Compact Tuning Circuit for Enhanced Linearity in a Ku-Band MMIC VCO

This work describes a compact, tunable linearization circuit able to provide enhanced linearity characteristics and low sensitivity of the VCO output signal, also regarding temperature variation between -30°C and +70°C. The proposed solution is applied to the design of a Ku-Band MMIC voltage-controlled oscillator in push-push configuration. The chip has been realized by UMS Foundry in HBT technology with the HB20M process. The measured oscillation bandwidth spans from 10.52 to 12.53 GHz with a tuning range of about the 16%; sensitivity has an average value of 200 MHz/V, while the phase noise at 100 kHz of frequency offset from the carrier at 11.7 GHz is -98.5 dBc/Hz.