研究单端腐蚀光纤布拉格光栅（FBG）在低折射率区（约1.333～1.360）对折射率与温度同时测量的理论模型，分析其主要结构参数对折射率灵敏度和线性度的影响，建立相应的线性近似理论和误差分析方法。理论仿真结果表明，可通过减小腐蚀区的直径或选择光栅周期较大的FBG制作传感器来提高折射率灵敏度，但这同时会降低传感器的线性度及增大折射率灵敏度的理论误差。在此理论分析基础上，设计并制作一个单端腐蚀FBG，进行相应实验研究，实验结果与仿真结果一致。

The theoretical model of single-end etched fiber Bragg grating (FBG) for simultaneous measurements of surrounding refractive index (SRI) and temperature in the low refractive-index area (from about 1.333 to 1.360) is researched, the effects of the structural parameters on the SRI sensitivity and linearity are analyzed in detail, and the corresponding methodology of linear approximation and error analysis is established. Simulated results show that the SRI sensitivity can be increased by reducing the diameter of the etched region or selecting the FBG with a relative bigger grating pitch for the fabrication of the sensor, however, these will cause not only the decline in the linearity but also the rise in theoretical error of the SRI sensitivity of the sensor. Based on the theoretical analysis, a single-end etched FBG is designed and fabricated for the corresponding experiments, the results of which are in accord with the simulated ones.