提出并实验验证了一种基于取样环的雪崩光电二极管(APD)增益调节与温度校正拉曼光纤温度传感系统,通过比较取样环在测温线与基线上的信号偏差对APD进行偏压调节,维持APD增益基本恒定,保证系统信噪比和稳定性;并在此基础上针对环境变化等不确定因素造成的不可避免的APD增益波动,以该取样环信号为参考信号对测温曲线进行校正解调,进一步提升系统测温精度。实验证明,较之传统的拉曼光纤温度传感系统,这种基于取样环的APD增益调节和温度校正方案能有效消除APD增益变化对传感系统的影响,显著提升系统在信噪比、稳定性和测温精确性等方面的性能,具有实用价值。 A sampling loop-based avalanche photodiode (APD) gain adjustment and temperature correction Raman fiber temperature sensing system is proposed and experimentally verified. By comparing the bias of the sampling loop with the baseline, the APD bias adjustment , To maintain a constant APD gain to ensure system signal to noise ratio and stability; and on the basis of uncertainties such as environmental changes caused by unavoidable fluctuations in APD gain to the sampling loop signal as the reference signal temperature measurement curve Correct demodulation, to further improve the system temperature measurement accuracy. Experiments show that compared with the traditional Raman fiber optic temperature sensing system, this sampling loop-based APD gain adjustment and temperature correction scheme can effectively eliminate the influence of APD gain variation on the sensing system and significantly improve the system’s signal-noise ratio, stability Sexual and temperature measurement accuracy and other aspects of performance, with practical value.