A Dual-Wideband Crossed Elliptical Disc Antenna with Reconfigurable Radiation Patterns for Multiband Applications

摘要

This paper presents the design of a crossed elliptical disc antenna with two broad operating bandwidths, which covers several widely-employed frequency standards: IEEE 802.11b/g (WLAN), IEEE 802.16 (WiMAX), GSM/UMTS and LTE. The antenna comprises a crossed elliptical radiator, step-fed transitions, L-shaped slits and split (defected) circular ground-planes. Moreover, the antenna is equipped with four switches to have reconfigurable options for the conical-beam radiation patterns. The fabricated antenna prototype offers the dual broad-bandwidths of 1.17 GHz (1.88-3.05 GHz) and 2.05 GHz (4.67-6.72 GHz), which cover the required frequency bands. The peak gains of the normal-mode conical beams are 3.05 and 5.91 dBi at 2.45 GHz and 5.5 GHz, respectively. It has the advantage of having main-beam directions pointing to nearly the same tilted angle for both operating frequencies, which is very useful for most simultaneous dual-band operations and ceiling-mounted installations.