Simultaneous Data Transmission and Sensor Interrogation in a Fiber Optical Sensor Network

This work presents a novel simultaneous optical data transmission and sensing concept. For this combined system, neither additional components nor spectral segregation is required. In contrary to other combined systems, the complexity does not increase in the presented approach. The sensor system is a code-division multiplex (CDM)-wavelength-division multiplex (WDM) system that is able to interrogate thousands of serial fiber-Bragg gratings (FBGs) within a single optical fiber. Simultaneously, this fiber is also used as the data transmission medium. In the proposed system, the performance limitations due to the shared broadband light source are mitigated by using different post-equalization schemes. The proof of concept is verified using an experimental setup, which demonstrates the interrogation of 1000 sensors and concurrent data transmission at a bit rate of 1 Gbps using a 1.6 km FBG sensor network employing a unified broadband light source.