【摘要】 本文提出了一种基于Bessel函数展开,在频域内精确确定光纤传感器3×3耦合器输出信号相位差的算法。在Mach-Zehnder干涉仪原理的基础上,通过建立3~3耦合器输出信号的数学模型和利用耦合器输出光功率的Bessel展开,完成了算法的理论推导,并且在实验室中进行了声学实验。数据处理结果表明,该算法能够较精确地确定3×3耦合器输出信号的相位差,且相位差与调制频率无关,与理论相符。更多还原

【Abstract】 An algorithm based on the Bessel function is presented to obtain the phase difference of the outputs of a 3×3 fiber-optic coupler in frequency domain.Based on the Mach-Zehnder interferometer,the mathematics model of the 3×3 fiber-optic coupler’s outputs is established,and on utilizing the model as well as expression of the Bessel function,theoretical derivation of the algorithm is given.The processed results of an acoustic experiment indicate that the algorithm is precise,and can be applied to any fiber optic sensor.The phase difference is found not to depend on the modulated frequency, that agrees with the theory.更多还原