Single-plate, two-in-one PIFA for 2.4 GHz modules

A two-in-one, planar inverted-F antenna (PIFA) having two signal feeding ports to operate in the 2.4 band for wireless module applications is proposed. The PIFA was of a symmetrical structure and can be fully integrated into the printed circuit board (PCB) of the module by through-hole soldering. The design was comprised of two sub-antennas of identical size and had two shorting portions linked by a horizontal strip. This structure allows the antenna to be stamped from one metal plate only at low cost and surface mountable as a dual-in-line package (DIP) component with four leads. Further, by incorporating a decoupling, neutralization line shunted at around the two shorting portions, the antenna port isolation less than -20 dB over the 2.4 GHz band can be achieved.