Improved Semi Analytical Model of Effective Area for a Step and ParabolicIndex Optical Fiber: Introduction of Increased Parameters in Fundamental Modal Field

Abstract

An accurate three parameter approximate solution of fundamental mode, to describe different propagation parameter of graded-index optical fiber has been presented. Due to three parameter optimization of the fundamental modal solution, the results are much more accurate for a wide range of optical fiber specifications. Employing variational technique, an estimation of effective area and effective index with proposed fundamental modal field are carried out. It has been shown that the results match identically with the exact available results for step and parabolic refractive index profile optical fiber. The accurate analytical expressions for the evaluation of effective area and effective index are formulated. Optimization of three parameters has been carried out for a wide range of normalized frequencies. Data for these parameters are also provided, which can be used directly while calculating different design parameters of an optical fiber.