Voltage-Controlled Oscillator at 6 GHz for Doppler Radar in Heart Sensing Applications*

In this paper, the design of a low noise voltage controlled oscillator (VCO) for heart sensing applications is presented. It is designed using Ansoft Designer software to have a low level of phase noise, therefore a bipolar transistor is chosen. Many effects such as the behavior of large signals, the parasitic effects of packages, etc., are taken into account. Hence, through a nonlinear analysis, quite accurate simulation results are provided.