A Compact Square Shaped Multiband Antenna loaded with Rectangular and U-slots for UMTS, WiMAx, WLAN and X-band Applications

A compact size of 25mmx25mm multi-band antenna is introduced with pent band operation. The antenna resonates at 2.2, 3.8, 5.1, 8.5 and 10.3 GHz with percentage bandwidth of 9.5%(2.1GHz-2.3GHz), 11.11 %(3.6GHz-4.0GHz), 4%(5GHz-5.2GHz), 6.09%(8.2GHz-8.7GHz) and 4%(10.lGHz-10.5GHz). These frequencies are achieved with a defected ground resembling a window pan structure and is accomplished by inserting three U- shaped slots in the patch. The frequencies at which the antenna resonates are used for different applications like UMTS, WiMAX, WLAN and also X-band. The design is made simple and compact to offer different applications under a single device. Optimal results are obtained which are in good agreement for multiband applications.