A comparison between two different excitations for Quasi-Yagi antennas

Abstract

A wide-band Quasi-Yagi antenna with loop excitation and a performance comparison between a dipole based Quasi-Yagi are presented, targeting the 5.8 GHz band. The proposed Quasi-Yagi antenna with loop excitation has a very wide measured bandwidth of 1.43 GHz which covers from 5.574-7 GHz. It has a very high Front-to-back ratio (FBR) of 18.7 dB with a ground size of 11 mm. The proposed antenna has a gain of 4.7 dBi, overall size of 60 × 60 mm2, and efficiency of 93%. The dipole based Quasi-Yagi antenna has a minimum measured bandwidth of 963 MHz and minimum FBR of 12 dB with a ground size of 18.6 mm. It has a gain of 3.56 dBi, overall size of 30 × 25 mm2, and efficiency of 73%. The superior efficiency, bandwidth, gain and FBR performance of the loop excited one comes at the cost of 79% larger size.