Compact double-sided printed omni-directional ultra wideband antenna

Abstract

Recently printed ultra wideband (UWB) antennas have great influence in communication fields. UWB antennas have a bandwidth wider than 500 MHz or a 20% fractional bandwidth. This influence of UWB antenna comes from the several unique advantages from wireless communications to radar applications. From the wireless communications view, the federal communication commission (FCC) allowed the use of unlicensed bandwidth from 3.1 GHz to 10.6 GHz [1], [2]. This means higher spectral efficiency than the typical narrowband and broadband technologies. Moreover as the bandwidth increases, the maximum capacity of a communication channel increases linearly, and not logarithmically increase as with the signal power, with a very low bit error rate. This gain in capacity is used in the transmission of high data rates in order of 1Gbps over very short distances less than 1m. The main characteristic in UWB technology is the integration of various kinds of passive and active elements for the sake of different applications [1]-[3]. From the 1970's printed microstrip technology became admired. The proposed antenna is compact, so it can be easily integrated with electrical elements. This article presents the design and fabrication of a compact double-sided printed omni-directional UWB antenna. The symmetry of the proposed design enhances the omni-directional properties of the antenna. Extensive modifications result in more compact antenna size compared to those obtained in [4]-[13].