Noise analysis of a VCO with automatic amplitude control

The noise analysis of a VCO with automatic amplitude control presented in this paper is intended to identify the most important noise sources in the circuit. The goal of this analysis is to find the optimum trade-off between noise performance and power consumption. The implemented VCO operates in the 300 MHz to 1.2 GHz frequency range using different external resonators. The measured VCO phase noise level is -106 dBc/Hz at 100 kHz offset from an 800 MHz carrier and it consumes 1.6 mA from a 2.7 V power supply.