基于全相位滤波技术的光纤表面等离子体共振传感解调算法

Optical fiber SPR sensing demodulation algorithm based on all-phase filters

基于生物样品检测对折射率传感的迫切需求,构建一种全光纤表面等离子体共振(surface plasmon resonance,SPR)系统,并针对其设计了基于全相位滤波技术的SPR特征波长传感解调算法.基于系统仿真,理论计算了光纤SPR传感器的折射率传感灵敏度.采用全相位滤波技术提取光纤SPR传感器透射光谱的特征波长,理论推导了全相位滤波器的解析表达式.实验结果表明,使用本算法的光纤SPR传感器折射率传感灵敏度为1640.4 nm/RIU,折射率检测的分辨率是7.36×10^(-4)RIU,与传统方法相比,有效提高了系统的检测精度和抗光源扰动性能,降低了实验成本.

Aiming at the urgent requirements for refractive index detection in the biological sample detection area, an all-fiber surface plasmon resonance（SPR） system is established in this paper. And the SPR characteristic wavelength demodulation algorithm is proposed for this system based on all-phase filter technique. According to the system simulation,the refractive index sensing sensitivity of the fiber SPR sensor can be calculated theoretically. By using the all-phase filter technique, the characteristic wavelength of the fiber SPR sensor can be extracted, and the theoretically analytical expression of the all-phase filter can be obtained. The experimental results show that the refractive index sensing sensitivity and the detection resolution of the fiber SPR sensor are 1640.4 nm/RIU and 7.36 × 10^（-4）RIU respectively by using this algorithm. Compared with the traditional methods, our algorithm can improve the detection precision and the anti-light-disturbance performance and reduce the costs as well.