High-Spatial Resolution DPP-BOTDA by Real-Time Balanced Detection

A novel scheme for distributed Brillouin sensing based on differential pump-width pair Brillouin optical time-domain analysis (DPP-BOTDA) with balanced detection of Brillouin gain is proposed and demonstrated. Compared with standard DPP-BOTDA, the proposed method allows us to reduce the measurement time and simultaneously improve the accuracy in Brillouin frequency shift estimation. Experimental results, carried out at 10-cm spatial resolution, demonstrate the effectiveness of the proposed method.