Sidelobe Suppression Method with Improved CLEAN Algorithm for Pulse Compression OTDR

Although pulse compression optical time domain reflectometry (PC-OTDR) exhibits high performance in spatial resolution and dynamic range, it inevitably introduces autocorrelation sidelobes, potentially impacting measurement accuracy. In this letter, an improved CLEAN algorithm is proposed to efficiently suppress sidelobes and enhance the peakto- sidelobe ratio (PSLR) of signals in PC-OTDR. The proposed method introduces an adaptive step factor instead of the traditional fixed factor to reduce the number of iterations. Compared to the traditional method, the proposed method achieves a 2.87 dB improvement of PSLR from a 10 km sensing fiber. In addition, the computation time cost is significantly reduced, which is 1.92 s less than that of the traditional CLEAN algorithm.