Design of VCO for 2.4GHz Wireless Applications Using Transmission Line Resonators

A voltage-controlled oscillator (VCO) employing on-chip coplanar waveguide (CPW) resonator is proposed for 2.4GHz wireless applications and comparative study between the proposed VCO and a conventional VCO which is composed of LC-tank resonator (LC-VCO), is carried out. By comparing the measured results on the fabricated chip on TSMC 0.35 mum BiCMOS technology, it has noted that the VCO employing on-chip CPW resonator is smaller in size by about 30% and frequency-tuning range is higher than LC-VCO. Phase noise is comparable but power consumption is deteriorated.