5 GHz polarization-diversity planar printed dipole-antenna for 802.11a WLAN applications

Detail numerical simulation, fabrication and experimental measurement of a 5 GHz polarization-diversity printed dipole-antenna are presented for IEEE 802.11a WLAN applications. Two 5 GHz orthogonal printed dipole antennas, each with a microstrip via-hole balun feeding structure, are combined and fabricated on a FR-4 printed-circuit-board substrate. A PIN-diode circuit is used to switch and select the desired antenna polarization. In the antenna design simulation, a full wave method of a three-dimensional finite-difference time-domain (FDTD) method is employed to analyze the entire structure of the printed antenna including the lumped elements of the polarization-selecting PIN diode switching circuit.