Circuit Model of Curved Ultra Wideband (UWB) Antenna

Abstract

This paper studies the effect of curved antenna performance on Ultra Wideband (UWB) characteristics, particularly on impedance bandwidth. A UWB antenna is designed, after which is curved and conformed onto cylindrical radius of 150 mm, 120 mm, 90 mm and 60 mm. The motivation of the study is to study the effectiveness of the antenna to be conformed onto non-planar structure applications, particularly on cylindrical body of air or land vehicles. It is observed that the degradation which occurs when the antenna is curved still adheres to the UWB characteristic of more than 500 MHz bandwidth. A circuit model is developed to understand the physics behind the antenna structure when it is curved or bent. The discontinuity of the antenna structure during the curving effect could be explained with the alteration of capacitive loading of the antenna, which is related to the electrical field of the antenna. The curved antenna proves to be suitable for UWB application and the results of its performance according to the UWB characteristics are discussed in detail.