Table of Contents
International Journal of Microwave Science and Technology
Volume 2009, Article ID 821515, 7 pages
Research Article

Bandwidth Enhancement of UWB Microstrip Antenna with a Modified Ground Plane

1Electrical Engineering Department, Mahidol University, Nakorn Pathom 73170, Thailand
2Electrical Engineering Department, King Mongkut's Institute of Technology North Bangkok, Bangkok 10800, Thailand

Received 19 January 2009; Accepted 22 July 2009

Academic Editor: Afshin Daryoush

Copyright © 2009 N. Prombutr et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


This article presents a bandwidth enhancing technique using a modified ground plane with diagonal edges, rectangular slot, and T-shape cut for the design of compact antennas. The proposed low-cost, compact-size circular patch antenna on 3 cm × 5.1 cm printed circuit board (FR-4) is designed and validated through simulations and experiments. Results show that the T-shaped ground plane with the presence of the diagonal cuts at the top corners and the rectangular slots can increase the bandwidth. Return losses of 19 and 26 dB for the first and second resonant frequencies, respectively, can be achieved when the depth of the diagonal cut is 5 mm, the dimension of each rectangular slot is 5 × 3  mm, and the T-shaped size is 8 × 4  mm, providing a 28.67% wider bandwidth than FCC standard.