Low noise multi-band voltage controlled oscillator using MEMS technology

Multi-band receivers are desirable in wireless communication systems. One key element of the RF front-end of the receivers is the voltage controlled oscillator (VCO). Out of the many options of implementing mult-iband VCOs, switched capacitor array and inductor array are popular. While MOSFET switches are commonly used in the switched capacitor array and inductor array, the noisy MOSFET switches impose large impact on the phase noise performance of the VCO circuits. This paper presents the design analysis and fabrication of a multiband differential Colpitts VCO using MEMS switches, the phase noise performance is 21 dB better than MOSFET switched VCO circuit.