Table of Contents
International Journal of Microwave Science and Technology
Volume 2016 (2016), Article ID 2648248, 11 pages
Research Article

A Frequency Agile Semicircular Slot Antenna For Cognitive Radio System

Banasthali University, Tonk, Rajasthan 304022, India

Received 24 November 2015; Revised 5 March 2016; Accepted 3 April 2016

Academic Editor: Chien-Jen Wang

Copyright © 2016 Rajeev Kumar and Ritu Vijay. 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.


A frequency agile antenna is proposed with its ground plane having a semicircular shaped slot which is capable of switching the frequency to different bands, one at a time, in the wide frequency range of 5.33 GHz to 9.90 GHz. To achieve frequency agility, switching of six RF PIN diodes which are placed along the slot length is done in various combinations. Frequency tuning ratio of about 1.85 : 1 can be achieved using this design. Results such as return losses, gain, bandwidth, and radiation patterns are presented in this paper.