Design and Analysis of Multi Band Notched MIMO Antenna for Portable UWB Applications

Abstract

A MIMO antenna having circular patch with CPW feeding is proposed in this paper. Design, Simulation, Fabrication and testing of MIMO antenna with different band notching characteristics are proposed in this paper. The designed antennas are suitable for portable UWB applications. UWB is the most promising technology which provides high data rate with in short range. In 2002 Federal Communication Commission (FCC) has approved a frequency band of 3.1–10.6 GHz for unlicensed applications. Within the band of UWB some of the wireless Communication bands with different frequencies are also operating. So to avoid interference, band dispensation characteristics are proposed. In this paper single dual, triple and quad band notch MIMO antennas are designed, simulated and tested and their results are reported. Elimination of interference with existing wireless bands like WiMAX, WLAN, X—Band Satellite Communication System and ITU is the prime focus of the paper. Concentric rings with rectangular split bricks are placed on the patch to eliminate the interference with the existing bands. Different antennas are designed and simulated using CST microwave studio software and the antenna parameters like Return losses (S11), Gain, VSWR, Radiation patterns and Correlation Coefficient are measured. Quad band notch antenna is fabricated using RT/Duroid 5880 substrate material with height 1.57 mm. To get better Isolation the antennas are placed vertically and a stub is placed in between the antennas. The quad band antenna able to notch WiMAX, WLAN, X—band and ITU band and port Isolation (S12) is very good and envelope correlation is below 0.001 in UWB frequency spectrum.