JCS_V4_N2_RP5 Jashan Preet Singh Ankush Kansal Journal on Communication Engineering and Systems 2277-5242 4 2 26 31 DGS, Microstrip Patch Antenna, CST, WLAN, WiMAX, VSWR A compact microstrip patch antenna with defected ground structure for WiMAX and WLAN applications is proposed in 2 this paper. The substrate used for this antenna is ROGER 3003 with dimensions 36 x 24mm . The front side of the antenna consists of the square shape strip enclosing a U shape strip, which is connected to the square through a small strip. The ground i.e. on the back side of the substrate, having curved shape, three square shaped polygons are etched through, that will provide the defected ground plane. The main outer square is fed by a microstrip feed line having 50W impedance. The defected ground structure will provide better impedance matching. This proposed antenna has large bandwidth (0.33 GHz (2.20-2.53 GHz), 1.15 GHz (3.09-4.24 GHz) and 0.86 GHz (5.03-5.89 GHz)), high gain (2.81 dBi (2.20- 2.53 GHz), 2.65 dBi (3.09-4.24 GHz) and 4.38 dBi (5.03-5.89 GHz)) and good antenna total efficiency. February - April 2015 Copyright © 2015 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=3342