An Injection Locking Method for Multiple FET Oscillators Suitable for Active Phased Arrays and Quasi-Optical Power Combining

In this paper we present a new method for the mutual injection locking of large numbers of FET oscillators. This is accomplished by taking advantage of the non-reciprocal nature of the FET, using the gate of the device as the locking signal injection port, and extracting the rf power from the drain port, which is relatively insensitive to an injected signal. This method is attractive for injection locked phased arrays and quasi-optical power combining schemes, where each oscillator is associated with an individual radiating element Results for a five element phased array prototype circuit operating at 6 GHz are reported.