基于布里渊光时域分析传感系统的格雷-差分脉冲混合编码技术

Golay-Differential Pulse Hybrid Coding Technology Based on Brillouin Optical Time Domain Analysis Sensors

鉴于布里渊光时域分析(BOTDA)传感系统中空间分辨率和传感距离存在相互制约的关系,提出了一种结合格雷(Golay)编码技术与差分脉冲对(DPP)技术的混合编码方法。该方法结合了Golay编码可提高系统信噪比以及DPP可改善系统空间分辨率的优点,相对于Golay-BOTDA的DPP方法能进一步提高系统信噪比,理论上在相同采样次数下信噪比可提升6dB。实验结果表明,采用改进的混合编码可以在25km光纤末端获得1.6m的空间分辨率。同时,与基于Golay-BOTDA的DPP方法相比,在相同的采样次数下系统信噪比提升了4.08dB。

In Brillouinoptical time domain analysis（BOTDA）sensing system,spatial resolution and sensing distance are restricted by each other.So a novel hybrid pulse coding technology which combines Golay code with differential pulse-width pair（DPP）is proposed.Compared with DPP based on Golay-BOTDA,this method shows a 6 dB enhancement of signal-to-noise ratio（SNR）in theory at the same sample times,as the Golay code can improve the SNR of the system and the DPP technology can ameliorate the spatial resolution.The experimental results indicate that 1.6 m spatial resolution could be achieved at the end of the fiber with the length of 25 km by using the hybrid coding technology,while the hybrid coding technology can get 4.08 dB enhancement of SNR compared with DPP based on Golay-BOTDA.