Multifunctional operation of a fiber Bragg grating in a WDM/SCM radio over fiber distribution system

A radio over fiber distribution system incorporating both sub-carrier multiplexing (SCM) and wavelength division multiplexing (WDM) technologies is presented. The SCM signal contains five 155-Mbit/s data channels, centered around 18.5 GHz with 450 MHz spacing. This signal is directly modulated onto three high-speed lasers with emission frequencies spaced by 50 GHz. Bragg filters are employed at the receiver base-station in order to both demultiplex the required optical channel and ensure that the detected signal is single sideband (in order to overcome dispersion limitations on the link). Our results show negligible degradation in system performance for the demultiplexing of the WDM signal compared with the back-to-back performance curves.