Impedance Matching of a Microstrip Antenna

Microstrip patch antennas play a very significant role in communication systems. In recent years, the study to improve their performances has made great progression, and different methods have been proposed to optimize their characteristics such as the gain, the bandwidth, the impedance matching and the resonance frequency. This paper presents a new method that allows to ameliorate the impedance matching, thus to increase the gain of a rectangular microstrip antenna. This method is based on the adaptation technique using a simple “L” matching network. The originality of this work is the exploitation of the principle of causality that permits to detect the problems of reflected waves and to obtain the suitable placement of components that constitute the matching circuit.