Wavelength-division-multiplexed distributed fiber Raman amplifier bus network for sensors

We experimentally demonstrate a novel application of distributed fibre Raman amplification to a bus network for the wavelength multiplexing of optical sensors. Each sensor is uniquely identified by reflection from a fibre Bragg grating (FBG) and the distributed gain allows the number of sensors to be increased without using costly remote amplifiers. We show how the topology allows the received powers from the sensors to be equalised, even though only one Raman pump wavelength is used and we investigate how the performance depends on the launched pump power. The spectral filtering of the FBGs, combined with the distributed gain, jointly reduce the noise and we report measured signal to noise ratios