A universal methodology for designing a UWB diversity antenna

Abstract

A universal methodology for designing a ultra-wideband (UWB) diversity antenna is presented in this paper. The main advantage of the methodology is that by using only a familiar symmetrical UWB antenna, a UWB diversity antenna with a compact size, wide impedance bandwidth and good isolation between two feeding ports can be designed conventionally. Another advantage of the methodology is that the distance between two radiators is almost equal to the distance between two feeding lines, thus a complicated structure to decouple the mutual interaction between two radiators is not necessary in the antenna design, and the configuration of the UWB diversity antenna is simple. As an example, a UWB diversity antenna with a compact size of 36 mm × 36 mm operating at a frequency range of 3.1–10.6 GHz designed by using a circular disc monopole UWB antenna is constructed, measured and analysed. The simulated and measured results show that across the UWB, the antenna can achieve a broad impedance bandwidth with good isolation of <−15 dB. The radiation patterns, gain and envelope correlation coefficient are also measured. Furthermore, to demonstrate the effectiveness of the methodology, another UWB diversity antenna designed by using another symmetrical UWB antenna which is a bevelled rectangular monopole UWB one is simulated.