Microwave photonic instantaneous frequency measurement with simultaneous parallel operation within a single optical fiber

A Microwave photonic system which simultaneously implements multiple parallel IFMs within a single optical fiber is proposed and practically demonstrated. Three optical carriers of different wavelength are modulated by the same RF signal and then differentially delayed. All three carriers are then mixed in a highly nonlinear optical fiber. The mixing products are separated and the optical power of each can be related to the input RF frequency. We demonstrate simultaneous acquisition of two distinct frequency measurement responses over the range from 2-40 GHz. This system is all-optical and requires no high-speed electronic components. Avenues for extending the number of simultaneous channels are identified.