Optically controlled oscillators for millimeter-wave phased-array antennas

A new approach for the design of optically synchronized millimeter-wave local oscillators based on a subharmonically injection-locked phase-lock-loop technique is introduced. The experimental results support the desired goal of frequency and phase coherency, phase shift control of millimeter-wave oscillators, and self-oscillating mixing to downconvert a millimeter-wave RF signal. Experimental results and theoretical analysis show the advantages of the proposed approach: larger locking range of two subharmonically locked oscillators, lower FM noise degradation, and smaller phase error caused by frequency detuning.