A new transfer matrix method for long-period fiber gratings with coupled multiple cladding modes is proposed and numerically characterized. The transmission spectra of uniform and non-uniform longperiod fiber gratings are numerically characterized. The theoretical results excellently agree with the experimental measurements. Compared with commonly used methods,such as using the fourth-order adaptive step size control of the Runge-Kutta algorithm in solving the coupled mode equation,the new transfer matrix method exhibits a faster calculation speed.
提出了一种双层电磁带隙(Electromagnetic Band Gap,EBG)结构,构建其电感电容(Inductance Capacitance,LC)等效电路并推算出双层EBG的谐振表达式,通过仿真软件对双层EBG结构上下两层的参数进行调节,分析各参数对电磁特性的影响规律,结果表明双层EBG可以产生两个零位相频率点,下层结构对应的零位相频率主要与下层的介质厚度及贴片大小有关,几乎不受上层的影响,而上层结构的谐振频率不仅与其自身参数有关也要考虑下层对其的影响,仿真结果与理论分析一致.该结构为EBG的具体设计和应用提供了指导依据.
