Compact Multiband Omnidirectional Antenna for Maximizing Frequency Coverage

A low-profile compact ultrawideband (UWB) monopolar antenna for maximizing frequency coverage is proposed. The proposed antenna comprises metallic wire-discone and printed meander-line dipoles. The antenna is designed in CST Microwave Studio for full-wave analysis. A coaxial feed method is employed. The structure is mechanically stable and has a reduced weight for mounting over vehicles. The antenna covers a wide frequency range with more than 4 GHz bandwidth in addition to the 900 MHz GSM band coverage and provides a good omnidirectional radiation pattern. The antenna's performance in the presence of different radome shapes is also investigated. A cost-effective and locally available rectangular plastic radome is used for measurements. The antenna is fabricated and measured in the presence of the radome. Simulated and measured results are in good agreement. The proposed design is compact with UWB characteristics making it suitable for multiple applications, e.g., GSM, Wi-Fi, WLAN, and vehicular.