基于电磁场理论的分段电极电场传感器的特性研究

【作者】 陈实；

【导师】 陈福深；

【作者基本信息】 电子科技大学 ， 光学工程， 2010， 硕士

【摘要】 在本文中主要利用基于电磁理论的分析方法研究光波导分段电极电场传感器系统中的分段电极结构对其传感特性的影响。通过比较不同的电极分析方法,得出了在分析分段电极结构对传感特性的影响时,采用数值计算方法最为合适。在本文中详细研究了用时域有限差分法和矩量法分析分段电极的电磁特性时需要考虑的问题及解决方法。利用有限积分方法得出了分段电极的不同结构对该传感器系统的传感特性的影响。其中分段电极结构的z方向的间隔在大于其中光波导宽度的范围内取值越小越好,y方向的间隔取值在10μm~70μm的范围内越大越好,边电极宽度与中间电极宽度的取值为:当边电极宽度一定时,中间电极宽度越接近边电极的宽度越好;当中间电极宽度一定时,边电极的宽度越大越好。分段电极总长度及分段电极的分段数两者需要由待测电场的频率响应带宽和灵敏度要求来综合考虑取值。对己制作完成的光波导分段电极电场传感器的进行实际测试,利用其测试结果与仿真结果对比分析,修正了之前分段电极结构的数值仿真中的误差以及验证了仿真模型的可靠性,并以此得出了仿真结果与实际测量结果之间的关系,通过该关系可以更加精确的指导设计满足不同频率响应带宽与灵敏度要求的光波导分段电极式电场传感器中的分段电极结构。并且新设计了两种比较有代表性的分段电极电场传感器中的电极结构。一种是可以工作在高频段5GHz~12GHz范围的电场检测中,当电场频率为9.5GHz时的电场传感器的灵敏度预计可达25mV/m;另一种是工作在低频0~3GHz范围的电场检测中,当电场频率为1.6GHz时的电磁传感器灵敏度预计可达3 mV/m。更多还原

【Abstract】 The structure of electric field sensor with segmented electrodes has been introduced by the operation principle of the optical waveguide electric field sensor and been uesed numerical analysis to analyse.And then the sensitivity and the frequency response are analyzed detailedly. The simulated results show that we can improve the structure to raise the characteristics of electric field sensor with segmented electrodes. The interval in the z direction of segmented electrodes is the smaller the better, and the interval in the y direction of segmented electrodes in the range of 10μm ~ 70μm is the bigger the better, The relation of the middle and the side of the electrode width is that when the width of side electrode is invariablenes, the width of the middle electrode is the closer to the width of the side electrode is the better; when the middle electrode’s width is invariablenes, the width of the side electrode is the more the better. To definite the value of the total length and the number of segmented electrodes is need to take the frequency response bandwidth and sensitivity into account.Some fabricated optical electric field sensors with segment electrode were used to test the sensitivity, the frequency response and the linearity dynamic range. The test results and simulation results is compared to amend the the simulation results, so we can design the structure of segmented electrodes more precise to meet the different frequency response bandwidth and sensitivity. In this paper ,I have designed two more representative of the segmented electrodes. The one is able to work in the high-frequency range of 5GHz~12GHz, when the electric field frequency is 9.5GHz,the electric field sensitivity of the sensor is expected to reach 25mV / m; the other one is able to work in the low frequency range of 0 ~ 3GHz, when the electric field frequency is 1.6GHz ,the electric field sensitivity is expected to reach 3 mV / m.更多还原