Synchronously realizing high spatial resolution and precise location for fiber fault attenuation event detection.

Abstract

Attenuation events are common fault types in optical fiber links, which are very important to identify and accurately locate them with high resolution. However, research on achieving high spatial resolution for fiber fault event localization in the field of optical time-domain reflectometry (OTDR) mainly focuses on reflection events; the precise identification of attenuation events is rarely reported. A chaotic OTDR technique based on attenuation extraction-correlation compression integrative demodulation (AECCID) is proposed to realize high spatial resolution and high-precision localization of attenuation events in optical fiber links. The positioning process and principle of AECCID are analyzed and verified by simulation. The location and length of the attenuation event are precisely recognized according to the demodulated positions of the two correlation peaks. The spatial resolution is only determined by the full width at half maximum (FWHM) of the autocorrelation curve of chaotic lasers, which breaks through the limitation of wide pulse width on spatial resolution. The proof-of-concept experimental results show that when the pulse width is 1 μs and the detector bandwidth is 130 MHz, the spatial resolution is improved from 100 m to 0.87 m compared with conventional single-pulse OTDR.