Design & Analysis of Miniaturized Asymmetric Coplanar Strip Fed Antenna for Multi-Band WLAN/WiMAX Applications

A novel, compact asymmetric coplanar strip (ACS)-fed multi-band antenna for Bluetooth/WLAN/WiMAX applications is proposed and discussed in this paper. The proposed antenna is composed of a simple monopole structure with a mirror-L shaped branch and two rectangular radiating strips. It has a very small size of 13.75 × 26mm2 including the ground plane. The mirror-L shaped branch excites a resonant mode at 2.5GHz, and on the other side, ACS-fed monopole structure with two rectangular strips (one horizontal and one vertical) excite the resonant modes at 3.3GHz and 5.75GHz respectively. By properly selecting the lengths and positions of these radiating branches, multiband operation with wider impedance bandwidth can be achieved. The measured and simulated results show that the antenna has impedance bandwidth of 200MHz (2.40–2.60 GHz), and 2800MHz (3.2–6.0 GHz), and it can cover the 2.4GHz Bluetooth, 2.4/5.2/5.8 GHz WLAN and 3.5/5.5GHz WiMAX bands. The resonances achieved with this technique can be tuned independently, and the equations governing the resonances are given and confirmed by parametric studies. The proposed technique is further validated by designing another antenna working at 1.8/1.9 GHz PCS, 3.5/5.5 GHz WiMAX, 5.2/5.8 GHz WLAN bands.