Effect of partial ground plane removal on the front-to-back ratio of a microstrip antenna

摘要

This study presents a new, simple method for enhancing the front-to-back ratio of a microstrip antenna (MSA) by a partially removed ground plane of the antenna. The effect of the partial ground plane removal in different configurations on the radiation characteristics of a MSA are investigated numerically. The partial ground plane removal reduces the back-lobe radiation of the MSA by suppressing the surface wave diffraction from the edges of the antenna ground plane. To further improve the front-to-back (F/B) ratio of the MSA, a new soft-surface configuration consisting of an array of stand-up split-ring resonators are placed on a bare dielectric substrate near the two ground plane edges. Compared to the F/B ratio of a conventional MSA with a full ground plane of the same size, an improved F/B ratio of 9.7 dB has been achieved for our proposed MSA.