Inverted Z and circular slot patch antenna for WLAN and WiMAX

In this paper, a compact multiband microstrip patch antenna with Z-shaped slots in the radiating patch is proposed. The antenna has a rectangular radiating patch on the top of the substrate and a ground plane on the bottom of it. A coaxial probe feeding is located along the orthogonal axis of the square patch radiator. Z-shaped slot on radiating patch gives a wider bandwidth with better return-loss. Various slots of this antenna are compared, and an optimized design is presented. Exploitation of Z-shape slot in antenna design makes the patch antenna flexible in terms of generating resonances and bandwidth as an order of the slots is increased. Several properties of the antenna such as impedance bandwidth, VSWR are presented.