相移谱的功率依赖特性对矢量布里渊光时域分析系统的优化设计具有重要意义。对增益型受激布里渊散射(SBS)相移谱进行了建模分析; 搭建了外差pump-Stokes系统, 在5 ~90 mW泵浦光功率和5 ?滋W~9 mW斯托克斯光功率范围内测量了400 m标准单模光纤的增益型SBS相移谱; 分析了Stokes光功率影响增益型SBS相移的机理。结果表明: 当固定Stokes光功率时, 增益型SBS相移范围与泵浦光功率成良好线性关系; 因泵浦耗尽作用的影响, 导致当Stokes光功率由5 ?滋W上升至8 mW时, 增益型SBS相移范围的泵浦光功率灵敏度由1.448 (°)/mW下降至1.156 (°)/mW。根据理论和实验结果, 对增益型VBOTDA系统进行了优化设计分析, 为其在长距离和高精度传感领域的发展奠定了基础。

The power dependence of phase shift spectrum is very important for the optimization design of vector Brillouin optical time domain analysis (VBOTDA) system. The phase shift spectrum of stimulated Brillouin scattering (SBS) gain was analyzed by mathematical modeling; the phase shift spectrum of SBS gain in 400 m long standard single-mode fiber was measured in a pump wave power range of 5-90 mW and a Stokes wave power range of 5 ?滋W-9 mW by a heterodyne pump-Stokes system; the mechanism of Stokes wave power dependence of SBS gain phase shift was analyzed. The results indicated that the phase shift range of SBS gain had a good linear relationship with pump wave power for a fixed Stokes wave power; the pump power sensitivity of phase shift range of SBS gain decreased from 1.448 (°)/mW to 1.156 (°)/mW with the increase of Stokes power from 5 ?滋W to 8 mW due to pump depletion. According to the theoretical and experimental results, the optimization design of VBOTDA system based on SBS gain was discussed, which provides a basis for the development of SBS gain based VBOTDA system in the field of long distance and high precision sensing.