Novel sensing network based on seamless integration of DAS and PON

Passive optical network (PON), as the backbone of optical fiber telecommunication networks, has been widely deployed in residential areas, urban centers and transportation infrastructures. When integrated with distributed acoustic sensing (DAS) technology, optical fibers in PON can be turned into a sensing network for real-time safety monitoring and early warning of facilities nearby. Here, we propose and demonstrate a sensing network based on the seamless integration of DAS and existing PON, by using an integrated time-varying frequency-shifted sensing-communication signal modulation format (ITVFS-SCSM), for the first time. The ability of ITVFS-SCSM that shares the signal generation and transmission equipment in PON is validated by experiment and a sensing sensitivity of 36.5 pε/√Hz@55Hz over a 25.45 km distance is achieved without any influence on the communication quality of PON. Such a novel sensing network based on the seamless integration of DAS and PON may lead to a new generation of PON-based sensing networks for use in real-time security monitoring and infrastructure management, etc.