New Frequency Plan and Reconfigurable 6.6 / 7.128 GHz CMOS Quadrature VCO for MB-OFDM UWB Application

This work presents a new frequency plan and a reconfigurable 6.6 / 7.128 GHz CMOS quadrature voltage-controlled oscillator (QVCO) with integrating differential switchable inductors. Based on this frequency plan, a further simple synthesizer architecture is proposed with only two PLL´s, two mixers, and one multiplexer. The QVCO is implemented with the mutual-coupling structure of two differential LC-tuned oscillator cores in a 0.18 mum RF CMOS technology. The core stages draw a total of 10 mA from the supply voltage of 2.0 V. The measured phase noise at 6.6 GHz is -116 dBc/Hz at 1 MHz offset. By utilizing a switched capacitance array, a tuning range of 860 MHz is achievable with four sub-bands. The figure of merits (FOM) is about -178 dB. According to the new frequency plan, this QVCO can be served as one of the original signal sources for the MB-OFDM UWB frequency synthesizer.