Microstrip backfire antenna with a square electromagnetically-coupled patch as feed element.

number: 
146
إنجليزية
department: 
Degree: 
Imprint: 
Physics
Author: 
Ali Hussein Taqi Al-Bayati
Supervisor: 
Dr. Rashid A. Al-Rashid
Dr. Saad M. Jassim
year: 
1995
Abstract:

In this study it has been shown that the bandwidth and the gain of a conventional square micro strip patch antenna excited in the TM0-mode operating in the X-hand region can be improved by applying the electromagnetic coupling medod and the backfire prespectivly . The electromagnetic coupling method was used to enhance the bandwidth of the antenna. . Different second patch sizes with different patch to patch separations were used for this purpose. The best results have been used to construct the final shape of the electromagnetic-coupled patch antenna. The backfire principle was used to improve the electrical characteristics as well as the gain of the (EMCP) antenna. For this purpose the (EMCP) was used to excite the backfire antenna. The reported results indicate that the backfire antenna has higher directive gain, broader bandwidth and symmetrical radiation pattern with narrow beam width and lower side lobes level in both the E-pIane and the H-pIane when compared with those of a single patch antenna. The backfire antenna with the (EMCP) as feed clement is compact, light weight, inexpensive and has small size. It can be used as feed clement in reflector antennas for communication purposes. Finally, the air-dielectric substrate antenna has been also investigated, the objective is to obtain results with high accuracy as possible.