16-Core BiCMOS VCOs With Phase Noise Down to-130 dBc/Hz at 1-MHz Offset From 20 GHz

This letter presents two 16-core 20-GHz VCOs in 55-nm BiCMOS technology proving an ultralow phase noise. Through a design approach careful to the issues of large oscillators arrays, the first voltage-controlled oscillator (VCO) achieves a phase noise as low as -130 dBc/Hz at 1-MHz offset, with 17.4% tuning range. The second VCO, exploiting diode-based coupling switches can be reconfigured 2-by-2 from 2- to 16-core, trading power and phase noise efficiently. An overall 12.5% tuning range is achieved, while the phase noise at 1 MHz scales from -120 to -128.8 dBc/Hz.