IMPACT OF ELEMENT LENGTHS AND SPACINGS ON THE PERFORMANCE CHARACTERISTICS OF YAGI-UDA ANTENNA

A. A. Raji

A. A. Raji Department of Electrical and Electronic Engineering, D.S. Adegbenro I.C.T Polytechnic, Eruku-Itori, Ogun State.

Keywords: Far zone patterns, front-to-back ratio, unequal spacing, uniform spacing

Abstract

This work examines the impact of element lengths and spacing on the performance behaviours of Yagi-Uda antenna. Four Yagi-Uda antenna types are used as candidates for numerical investigation including Yagi-Uda antenna of uniform lengths of directors with uniform spacings (YUDUS), Yagi-Uda array of uniform lengths of directors with non-uniform spacings (YUDNS), Yagi-Uda array of varying lengths of directors and uniform spacings between directors (YVDUS), and Yagi-Uda antenna varying length of directors with non-uniform director spacings (YVDNS). Upon utilizing method of moments procedure, far-zone radiation field, directivity, front-to-back ratio, and side lobe radiation emerge and are therefore utilized as performance metrics for analyzing the behaviour of those Yagi-Uda antenna types. It is observed that YVDNS exhibits better directive main lobe radiation and lower side lobe radiation than others. It is observed also that YVDNS has maximum front-to-back ratio which suggests better electromagnetic energy radiation than others. These characteristics properties of YVDNS design commend the antenna for a number of practical applications more than any other type of Yagi-Uda antenna.