Multiband antenna for WLAN, WiMAX and future wireless applications

A novel multiband microstrip patch antenna suitable for WLAN and WiMAX applications is proposed in this paper. The antenna primarily comprises of a defected ground plane and an inverted, upright chair type patch. The antenna resonates at four frequencies, 3, 3.5, 4.1 and 5.3 GHz with bandwidths of 640, 420, 620 and 150 MHz respectively, which makes it suitable to use for WLAN, WiMAX, and other RF communications. The miniature size of $25 \times 19 \times 1.53$ mm 3 gives this antenna a cut above the rest, which is available in larger sizes. To evaluate the performance of the proposed antenna, CST Microwave studio has been used. The return loss, gain, radiation pattern, the surface current has also been analyzed here.