Miniaturization and Gain Enhancement of Array Antenna for Dual Band RADAR System

Abstract

This paper presents a $2\times 2$ hexagonal shaped array antenna with dual band characteristics at 2.4 GHz and 5.8 GHz. For the enhancement of gain and miniaturization of array antenna, CSRR is etched into the ground plane. Corporate feed network is chosen for the equal amplitude distribution at the input of patch elements. The CSRR structure incorporated into the design behaves like a metamaterial which has negative permeability and permittivity which results into negative reflective index. So transmitted wave could not pass into the structure and it gets reflected back from the structure. It also disturbs the current distribution at ground plane. This work achieves efficiency up to 83%.