Bandwidth enhancement of microstrip patch antenna using different structures of dielectric resonator

In this paper, DR (Dielectric Resonator) loading technique is implemented in a narrowband microstrip patch antenna for increasing impedance BW (bandwidth) and rad. (radiation) efficiency without much affecting its performance. The original patch antenna has 2.2% impedance bandwidth and 92.7% radiation efficiency. The BW enhancement is achieved without changing feed location or any antenna dimension. Position of DR on the patch surface for maximum percentage bandwidth is optimized and it is at the center of feed location. So the additional DR is placed at the center of feeding point. Here four different structures of DR are proposed for loading on the proposed antenna. In the first structure, DR disc is loaded, while in the second structure, loading is done using coaxial cylindrical DR. In the third structure DR brick is used for loading, while in the forth structure cylindrically cut DR brick is loaded on the feed point. Further improvement in BW and rad. efficiency is achieved by increasing substrate thickness and keeping all other dimensions same as they were.