Internal two-PIFA system with comparable polarization radiation for metal back cover tablet

A two-PIFA system suited to functioning inside the tablet computer with a complete, metal back cover for 2.4GHz wireless local area network (WLAN) operation is proposed. The antenna was constructed by stamping a flat plate and bent two times to form a compact structure. The PIFA was fed and short-circuited at the top patch above the antenna ground with a vertical ground wall connecting there between. The two PIFAs were symmetrically located on the metal cover and grounded therein. The results showed that comparable E_θ and E_φ fields were obtained for the tablet used in the three major positions, the landscape, portrait, and bottom-down modes.