A planar microstrip‐fed tri‐band filtering antenna for WLAN/WiMAX applications

In this article, a combination of microstrip bandpass filter and antenna is presented to give sharp response at desired frequency bands along with very low insertion loss. Three single bandpass filters, designed at wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) frequency bands, are integrated into a tri‐band bandpass filter. An ultrawideband antenna is further added to the structure. The antenna operates in 2.23–2.587, 3.468–3.816, and 5.345–5.607 GHz, suitable for WLAN 2.4 GHz and WiMAX 3.5/5.5 GHz applications. The proposed tri‐band filtering antenna shows monopole‐like radiation patterns in the desired frequency bands with high out‐of‐band rejection. Good agreement between simulated and measured results validates possible applications.