Design of novel super wide band antenna close to the fundamental dimension limit theory

Abstract

This paper investigates the design and practical implementation of a Super Wide Band (SWB) antenna along with the application of fundamental bandwidth limitation theory of small antennas in the proposed design. The antenna is designed on a material with permittivity, εr = 3 where the patch metallization height is maintained as 0.035 mm. The designed antenna is then modified by enhancing the copper patch with an additional layer of 28.5 mm thickness. The proposed antenna achieves a huge frequency range with a ratio bandwidth starting from 96.96:1 to as high as 115.10: 1. The designed antenna operating band with thinner height starts from 1.65 to 160 GHz while with the added patch metallic height, the antenna operates from a minimum of 1.39 to 160 GHz with an average nominal bandwidth of more than 158 GHz. By enhancing the patch height, the antenna spherical volume is utilized more efficiently. Using this principle, the antenna impedance bandwidth is augmented while a reduction in electrical size is achieved. A comparison with the fundamental theories by Chu and Mclean illustrates that the designed SWB antenna electrical size exceeds Mclean and nearly touches the Chu fundamental limit curve. This eventually offers the maximized bandwidth with the most compact size for an SWB antenna. The designed antenna with thinner patch metallization height is practically fabricated and measured up to 67 GHz using Vector Network Analyzer to provide experimental validation.