Photonic approach for microwave frequency measurement with adjustable measurement range and resolution using birefringence effect in highly non-linear fiber.

We experimentally demonstrate a novel approach for microwave frequency measurement utilizing birefringence effect in the highly non-linear fiber (HNLF). A detailed theoretical analysis is presented to implement the adjustable measurement range and resolution. By stimulating a complementary polarization-domain interferometer pair in the HNLF, a mathematical expression that relates the microwave frequency and amplitude comparison function is developed. We carry out a proof-to-concept experiment. A frequency measurement range of 2.5-30 GHz with a measurement error within 0.5 GHz is achieved except 16-17.5 GHz. This method is all-optical and requires no high-speed electronic components.