Dual-band Horizontally Polarized Omnidirectional Printed Antenna

Horizontally polarized omni-directional printed antennas are of low profile and cost so that they have very fine application perspectives in communication systems such as WLAN. This dissertation focuses on the investigation of the dual band horizontally polarized omni-directional printed antenna covering 2.4-2.5GHz (WLAN including Blue-tooth band) and 5.15-5.3GHz (HiperLan2 band). The study about it has been carried out in the following aspects:1. Characteristics of the basic antenna style-loop antenna are analyzed and furthermore Alford wire loop structure and its radiation principle are introduced. Besides, printed Alford loop antenna is presented combining Alford loop principle with printed antenna structure.2. Much attention has been put into the main structure and performance of these printed antennas which are either circular or rectangular annular. They are simulated and optimized using HFSS software and proved to be compact, small and light. The different shaped antennas are also compared in parameter and dimension, and some useful conclusions are drawn.3. Based on the single band circular annular loop antenna, a dual band horizontally polarized omni-directional printed antenna covering 2.4-2.483GHz and 5.15-5.3GHz band is developed. The parameters of the developed antenna are optimized with HFSS simulation software. The measured results show that its VSWR is less than 3 at 2.35-2.47GHz and 5.11 -5.26GHz, which can basically meet engineering needs.