A New Implementation of UWB CRLH Based Antennas for Wireless Communications

In this article, a novel ultra wideband (UWB) small antennas based on the composite right/left-handed transmission lines structures are proposed. The antennas are pre- sented with best in size, bandwidth and radiation patterns. Their physical size and the operational frequency depend on the unit cell size and the equivalent transmission line model parameters of the CRLH-TL. To realize characteristics of frst proposed model, Q-shaped gaps printed into rectangular radiation patches are used. The antenna based on composite right/left-handed transmission lines is composed of two unit cells, each of which occupies only 10.8 x 8.6 mm and covers the 2.7{9.3 GHz bandwidth for VSWR < 2. The peak gain and radiation effciency, are 5.78 dBi and 42.1% 9.3 GHz, respectively. Moreover, the second designed antenna has the same size and enhancement bandwidth, gain and radiation effciency than the rst proposed antenna with similar design procedure. It is constructed of the printed Q-shaped four unit cells. The length, width and height are 21.6, 8.6 and 1.6 mm, respectively, and it covers 4.1{11.7 GHz bandwidth for VSWR < 2 having highest gain (7.18 dBi) and radiation effciency (92.69%) at 4.1 GHz.