Review of Impedance Matching Networks for Bandwidth Enhancement

A number of techniques can be used to eliminate reflections when the characteristic impedance of the line and the load impedance are mismatched. Impedance matching techniques can be designed to be effective for a specific frequency of operation (narrow band techniques) or for a given frequency spectrum (broadband techniques). The purpose of this paper is to make a comparative study on bandwidth enhancement techniques of impedance matching networks that help to overcome the bandwidth constraint of transmission line. In this paper work narrowband impedance matching networks like lumped element, single stub, double stub, quarter-wave transformer and broadband impedance matching techniques like binomial, and chebyshev are studied. Keywords— Bandwidth, Narrowband matching, Characteristic impedance, Broadband matching, Reflection coefficient