Frequency Tunability Study of an SRR and SNG Metamaterial Integrated UWB Antenna

A new technique to design a metamaterial (MTM) inspired frequency reconfigurable ultra-wideband (UWB) antenna is presented in this paper. The proposed antenna comprises a circular disc UWB antenna having two MTM unit cells. MTMs are placed at a slant of ±30° from the centre of the circular patch and two diodes (D1, D2) are used to switching them to the circular disc. The circular disc conventional UWB antenna can operate from 3-10 GHz. The magnetic resonance of a circular split-ring resonator (SRR) from 1.75-2 GHz and two epsilon negative bands of a single negative (SNG) MTM from 1.54-2 GHz and 3.4-4.2 GHz are employed to achieve the frequency tuning purpose. When the SRR is connected to the circular disc, it offers additional impedance BW in the lower frequency region (1.8-2.9 GHz) along with UWB operation. Another narrow band feature at L1 GPS band beside the UWB operations can also be accessed by switching an SNG MTM to the circular disc. Moreover, the proposed antenna demonstrates the band rejection capability ranges from 3.2-3.8 GHz and 4.1-4.7 GHz. Also, the simulated gain at operating bands 1.51-1.62/1.8-10/3-10/4.8-10 GHz are 1.7-2.75/1.75-2.8/2.95-2.75/2.15-4.06 dBi. So, the proposed MTM motivated frequency reconfigurable antenna could be a potential candidate for GPS, UWB, and cognitive radio (CR) system.