We propose a novel BOTDA that can measure a BFS change appearing on a time axis with a single-shot measurement by using a frequency-swept probe pulse. The proposed method employs a very simple laser control and detection system, without precise test light frequency control, and with an oscilloscope. We demonstrate a fast BFS distribution measurement completed within 0.33 s with 1.8 MHz BFS accuracy for a 10 km range, and discuss its advantages compared with conventional BOTDA.
The in-service loss monitoring of branched fibers in passive optical networks (PONs) is demonstrated in the field for the first time. End-reflection assisted Brillouin analysis employing a frequency shift averaging technique compensated for the variation in the Brillouin gain profile of installed optical cables. Complete loss monitoring for individual branched fibers in deployed PONs was successfully achieved.
We present a novel Brillouin time domain analysis configuration for monitoring parallel fiber networks. By employing branch length manipulation, the new probe pulse arrangement improves the system dynamic range compared with a previously reported approach that uses a single pair of pump and probe pulses. This technique is promising in parallel fiber sensing that enhances the system reliability.