A compact monopole antenna for wireless applications with enhanced bandwidth

Multiband antennas have the advantage of supporting multiple standards simultaneously which is the need in recent communication system applications. In this paper, a compact annular ring shaped antenna with an L-shaped slot has been designed. An additional slot near the feed point for minimizing the return loss S11 at 2.9 GHz is proposed. For enhancement of bandwidth for covering wide range, an upper bevel cut with defected ground plane has been used. Two C-shaped slot are etched in the ground plane for improving S11 at 7.5 GHz. The stepwise design procedure along with parametric analysis has been thoroughly discussed. The antenna has been designed with an FR4 substrate and fabricated using gold plating for increasing antenna durability and lifetime. The proposed compact monopole antenna has dimensions 50.9 × 33 × 0.8 mm3. We have also analysed impedance bandwidth, reactance and resistance curve, return loss, radiation plots and housing effect. Efficiency obtained at 2.9 GHz, 3.4 GHz and 7.5 GHz is above 85% with S11 around −20 dB.