Design of 5.5 GHz Band Notching for Printed UWB Pentagonal Monopole Antenna

This paper proposes three techniques band notching of 5.5 GHz for the printed UWB pentagonal monopole antenna. By embedding narrow slits including the inverted C-shaped and inverted open- end triangle-shaped into the patch of monopole antenna, frequency band rejection of 5.5 GHz is achieved. Another technique, by placing small strip in rectangle shape embedded in CPW central feed line, frequency rejection is obtained. The measurement S11 results of the proposed antennas show the frequency coverage of 3.1-10.6 GHz with frequency rejection from 5.2 to 5.8 GHz. All proposed antennas show radiation patterns with nearly omni-directional in xz plane and likely bi-directional in yz plane. The maximum gain of 4.5 dBi is reached at 7.5 GHz and minimum gain of −0.89 dBi at 5.5 GHz are also obtained. It is obviously that the proposed antennas show potential to reduce electromagnetic interferences at 5.5 GHz band, therefore they are suitable for various UWB applications.