A 1–9 GHz Linear-Wide-Tuning-Range Quadrature Ring Oscillator in 130 nm CMOS for Non-Contact Vital Sign Radar Application

A 1-9 GHz linear-wide-tuning-range quadrature ring oscillator has been designed and fabricated in UMC 0.13 ¿m CMOS process. The chip was wire-bonded on printed circuit board and tested, showing a liner tuning range from 1 GHz to 9 GHz. Comparative study with other differential ring oscillators demonstrates the advantages of this design in low power consumption and linear-tuning. The oscillator was designed as the voltage controlled oscillator (VCO) for a non-contact vital sign radar sensor. It can also be used for other applications such as ultra-wideband (UWB) impulse radio and clock recovery in broadband optical communications.