SOME EXPERIMENTAL INVESTIGATIONS ON MICROSTRIP ANTENNA ARRAYS

Abstract

Microstrip antenna arrays are developed for satisfying the requirements of advance military and commercial application because of their several attractive features such as ease of construction, lightweight, low cost, and their compatibility with solid-state devices etc. Microstrip array are significant to increasing needs for wide bandwidth, radar, communication systems, high power and additional pattern control features. In the present work, two types of feeding technique for an aperture-coupled microstrip antenna array have been studied: series-feed array and corporate-feed array. Design for series-feed microstrip array antenna of two types is first presented; In one case, the four-elements are fed in series by traveling wave microstrip line. Whereas in the other case, the patches are enclosed in cavity and the effect of cavity height on its performance characteristics are studied. Two configurations of corporate-feed array have also been studied. In one case, the four-elements are fed by corporate-feed array. Whereas in the other case, the patches were placed into cavity and the effects of cavity height on antenna characteristics are studied. Experimental results have been reported here on input impedence, input VSWR, bandwidth, radiation pattern and gain for each antenna at operating frequency of 9 GHz. The gain and VSWR bandwidth of cavity-backed antenna array are among the best for microstrip antennas array.