Quadrature VCO Using BAW Resonators

Digital RF transceiver architectures increasingly require quadrature (I/Q) local oscillator sinusoid generation, where the phasenoise and power consumption of the quadrature voltage controlled oscillator (QVCO) have a significant impact on the system performance. The relevance of VCO power consumption becomes even more urgent due to the demand for implementations of ultra-low power short-range wireless transceivers. This work presents the first bulk-acoustic wave (BAW) resonator-tuned QVCO and introduces a new oscillator coupling mechanism for quadrature signal generation, which is demonstrated on both a BAWand an integrated LC-tuned QVCO. The design focus is optimization for ultra low power consumption. Oscillators using high quality factor (Q) BAW resonators have been demonstrated to provide excellent phase noise, supply pushing, and power consumption performance [1]. This work demonstrates a 600μW BAW-based QVCO, providing a figure-of-merit (FOM) significantly greater than the current state-of-the-art. An identical QVCO using an integrated LC-tank with 600μW power consumption is presented for direct comparison with the BAW-tuned QVCO.