In this thesis, various kinds of theory to account for injection locking and pulling in the literature are studied and compared. On this basis, this thesis derives a generalized locking equation when injection signal is modulated signal. In applications, a novel RF sensing circuit for cognitive radio system is proposed using injection locking and frequency demodulation. Detailed circuit architecture and sensing principle are also described in the thesis. In implementation, a hybrid VCO and a CMOS VCO have been separately used with the other components to establish the RF sensing circuit. The simulation relies on a discrete-time numerical method. Comparison between measurement and simulation shows very good agreement. This RF sensing circuit can simultaneously sense frequency and power with a sensing speed up to 400 MHz/ms and a sensing sensitivity as low as -80 dBm, showing that the presented prototype can fast and reliably sense frequency and power for analog and digital modulation signals.

This thesis is composed of three parts. In the first part, various kinds of theory to account for injection locking and pulling in the available literature are studied and compared. In the second part, this thesis proposes an experimental setup with self-made hybrid VCO and commercially available equipments and components to measure the characteristics of injection locking and pulling. This thesis also performs simulation to verify the measured results. The simulation mainly relies on the circuit envelope technique that has been developed in our laboratory. Comparison between measurement and simulation shows good agreement in the injection-locking characteristic curves and the injection-pulling spectrum characteristics. In the third part, this thesis carries out an RFIC design for a fractional-N frequency synthesizer with special features on quantization-noise cancellation and PLL nonlinearity reduction using TSMC 0.13£gm CMOS process.