Uniplanar coupled‐fed printed PIFA for WWAN/WLAN operation in the mobile phone

A coupled‐fed printed planar inverted‐F antenna (PIFA) with a compact uniplanar structure for easy implementation in the mobile phone for WWAN/WLAN operation is presented. The printed PIFA occupies a small area of 10 × 60 mm 2 and provides two wide operating bands (the lower and upper bands) at about 900 and 2000 MHz for covering GSM850/900/DCS/PCS/UMTS/WLAN six‐band operation. The printed PIFA is formed by two coupled‐fed PIFAs of different sizes, a longer radiating/coupling portion and a shorter radiating/coupling portion. Owing to the use of the coupling feed, both of the two portions can generate dual‐resonance excitation, with the longer portion providing a wide lower band for GSM850/900 operation and the shorter portion providing a wide upper band for DCS/PCS/UMTS/WLAN operation. In addition, the lower and upper bands of the printed PIFA can generally be controlled separately by the longer and shorter portions, making it easy for fine tuning of the desired operating bands in practical applications.