Design of a 1.29-1.61 GHz LC-VCO with Improved Phase Noise and Figure-of-Merit (FoM(T)) for GPS and Satellite Navigation

This paper demonstrates a low-phase noise and high FoM T differential CMOS LC-VCO working at 1.29-1.61 GHz. An RC filter tail current source is used in this design to reduce the second-harmonic oscillation phase noise. The VCO is implemented in 180 nm process technology. The post-layout simulation results indicate that this proposed VCO operates faithfully in the 1.29-1.61 GHz band with a frequency tuning range (FTR) of 320 MHz. By using inversion mode N-MOSFET varactor, the designed VCO obtains 22.06% FTR. The phase noise of the VCO is -130.21 dBc/Hz at 1 MHz offset frequency. It consumes 4.01 mW average power from 1.3 V supply. The cell area occupied by the design is 534 x 489 mu m(2). Figure-of-merit considering FTR (FoM(T)) is -194.14 dBc/Hz at 1 MHz offset frequency, phase noise and average power consumption. The proposed VCO can be used for low-phase noise GPS and satellite navigation.