We propose a novel denoising method based on empirical mode decomposition (EMD) to\nimprove the signal-to-noise ratio (SNR) for vibration sensing in phase-sensitive optical time domain\nreflectometry (Ãâ? -OTDR) systems. Raw Rayleigh backscattering traces are decomposed into a series of\nintrinsic mode functions (IMFs) and a residual component using an EMD algorithm. High frequency\nnoise is eliminated by removing several IMFs at the position without vibration selected by the Pearson\ncorrelation coefficient (PCC). When the pulse width is 50 ns, the SNR of location information for the\nvibration events of 100 Hz and 1.2 kHz is increased to as high as 42.52 dB and 39.58 dB, respectively,\nwith a 2 kmsensing fiber, which demonstrates the excellent performance of this new method.
Loading....