Coupled-oscillator arrays: beamsteering without phase shifters

Arrays of coupled oscillators have been proposed as signal sources for beam-steered array antennas by York et al., (1993, 1997, 1999), and their coworkers. The engineering considerations for designing an array based on coupled oscillators is discussed herein and performance features are compared with those of conventional phased arrays wherever possible. It is shown that there is a direct relationship between departure of the free-running frequencies of individual oscillators and phase errors in the signal produced by the oscillator. Considerations for minimizing the sensitivity to frequency errors and the achievability of reproducible free running frequencies are discussed. The correspondence between the phase of an individual oscillator in an array in phase-shifted state and the phase setting of a phase shifter is discussed