Brillouin Threshold Measurement in Optical Fibres

Abstract

Stimulated Brillouin Scattering (SBS), is a nonlinear scattering effect in optical fibre which occurs due to inelastic scattering of an excited photon to a lower energy photon. In this paper we present the simplest way of measuring the transmitted  pump power and the backscattered Stokes power using universal bidirectional fibre of different lengths. From the theoretical simulation we found out that threshold decreases with length and increases with effective core area. Also, temperature rise in the fibre causes an increase in Stokes power for input powers below 7dBm. The knowledge of Brillouin threshold is essential to configure optical networks and to control systems based on SBS.