Adaptive spatially injection-locked heterodyne receiver

Abstract
An adaptive photorefractive heterodyne receiver that uses a spatially injection-locked oscillator is demonstrated. The local oscillator consists of a resonator of two facing phase-conjugate mirrors with gain. When a signal containing complex spatial information is injected into the resonator, the internal resonator modes are spatially locked to the injected signal. The signal and local oscillator are at different frequencies and are mutually incoherent. The local oscillator will adapt to different input conditions. Significant heterodyne response is obtained when several thousand spatial modes are received.