Analysis and Design of a 54 GHz Distributed "Hybrid" Wave Oscillator Array With Quadrature Outputs

An array of distributed oscillators for millimeter-wave phased arrays combines local oscillator (LO) generation and distribution, leading to a phase noise improvement proportional to the number of array elements. The unit "hybrid wave" oscillator (HWO) consists of a rotary traveling-wave oscillator with quadrature outputs, coupled to the other units through standing-wave oscillators. A phase noise analysis for distributed oscillators based on impulse-sensitivity functions (ISF) is introduced and applied to study the proposed oscillator and arrays of it. A standalone oscillator and a 4-elements array implemented in a 65 nm CMOS technology have a measured phase noise of -125 dBc/Hz and -131 dBc/Hz respectively at 10 MHz from the 52 GHz carrier. Each unit consumes 36 mW corresponding to a FoM of - 183.7 dBc/Hz. The tuning range is from 51.9 to 56.5 GHz.