Filter Circuit with Periodically Arranged Nonuniform Microstriplines Having Linewidths Determined by Fermi-Dirac Distribution Function

Abstract

In this paper, a broadband bandstop filter consisting of periodically arranged nonuniform microstriplines is presented. The Fermi-Dirac distribution function is used for determining the linewidth of the microstriplines. The advantage of using this function is that the shape of the transmission line can be varied by varying a parameter of the function. Calculation and measurement results showed that the filter provides frequency characteristics between those obtained by using a step function and those obtained by using a linear function. As a result, broadband bandstop filter with a center frequency of 5.25 GHz and bandwidth of 3.58 GHz was obtained.