Adaptively Phase-Shift Controlled Self-Injection Locked VCO


IEICE TRANSACTIONS on Electronics   Vol.E98-C   No.7   pp.677-684
Publication Date: 2015/07/01
Online ISSN: 1745-1353
DOI: 10.1587/transele.E98.C.677
Type of Manuscript: Special Section PAPER (Special Section on Microwave and Millimeter-Wave Technology)
Category: Active Circuits/Devices/Monolithic Microwave Integrated Circuits
self-injection locked oscillator,  phase noise,  delay lines,  phase-shift control,  

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An adaptively phase-shift controlled self-injection locked VCO is described. A self-injection locking technique is effective to reduce phase noise. However, a conventional self-injection locked VCO has drawbacks of discontinuous frequency sweep which means narrow bandwidth, and large variation of phase noise. Our proposed adaptively phase-shift controlled self-injection locked VCO overcomes these drawbacks by detecting phase-shift of the self-injection feedback and controlling the phase-shift depending on sweep of the oscillation frequency. This paper describes analysis of relationships between the discontinuity and feedback phase-shift of the self-injection locked VCO. In addition, a VCO-IC which includes a Ka-band VCO and a phase detector is designed and fabricated in 0.18um SiGe BiCMOS technology. Measurement results of the proposed self-injection locked VCO using the fabricated IC show the improvement to the drawbacks. In the proposed self-injection locked VCO, the oscillation frequency sweep is continuous and the phase noise variation is less than 5 dB.