Multi-band antenna for different wireless applications

A small multi-band compact antenna is presented. The antenna is designed on Roger RT/duroid 5880 with dielectric constant 2.2, multi-band operations is achieved by inserting a slot on the top patch. The antenna has wide impedance bandwidth at 1.2, 1.6, 2.4 and 2.6 GHz with Gain 4.2, 1, 5 and 2 dBi respectively. The bandwidth before adding the shorting wall and the slot was 3.72%, whereas after adding the shorting wall and the slot the bandwidth get wider to 31.9% at the centre of 1.4 GHz. The radiation pattern has acceptable response with low cross polarization at both E-plane and H-plane. The overall dimension of the ground plane is 70 times 70 times 1.5 mm.