Long-range high spatial resolution optical frequency-domain reflectometry based on optimized deskew filter method

Abstract

We present a long-range high spatial resolution optical frequency-domain reflectometry (OFDR) based on optimized deskew filter method. In proposed method, the frequency tuning nonlinear phase obtained from an auxiliary interferometer is used to compensate the nonlinear phase of the beating signals generated from a main OFDR interferometer using a deskew filter. The method can be applied for the entire spatial domain of the OFDR signals at once with a high computational efficiency. In addition, we apply the methods of higher orders of Taylor expansion and cepstrum analysis to improve the estimation accuracy of nonlinear phase. We experimentally achieve a measurement range of 80 km and a spatial resolution of 20 cm and 80 cm at distances of 10 km and 80 km that is about 187 times enhancement when compared with that of the same OFDR trace without nonlinearity compensation. The improved performance of the OFDR with the high spatial resolution, long measurement range and short process time will lead to practical applications in real-time monitoring and measurement of the optical fiber communication and sensing systems.