SBS-Based Fiber Optical Sensing Using Frequency-Domain Simultaneous Tone Interrogation

A frequency-sweep-free method for stimulated Brillouin scattering (SBS)-based sensing is proposed, having the potential for fast acquisition characteristics. The Brillouin gain spectrum and the Brillouin frequency shift are determined using multiple frequency tones for both the probe and pump. While in this paper, continuous wave probe and pump waves are used to prove the feasibility of the concept, an extension to fast distributed sensing, using pulsed pumps, is also described.