A high speed SiGe VCO based on self injection locking scheme



This paper discusses the design and implementation of an inductorless differential VCO with a maximum oscillation frequency of 20 GHz, in a 47 GHz SiGe process technology. The VCO is based on afull-wave rectification frequency-doubling technique, applied to a half rate differential single-stage feedback oscillator. It also benefits from a new circuit phenomenon named hereinafter Self Injection Locking (SIL). The implemented VCO has an area of 0.5 mm2 and features a remarkably high ratio of VCO frequency to process fT. Based on measurement results, the VCO consumes a DC power of less than 165 mW and exhibits a phase noise of -96 dBc/Hz at 1 MHz offset