Modal Analysis of Triple Frequency Band Notch Ultra-Wideband Monopole Antenna

A low profile, printed triple band-notched ultra wideband antenna is investigated. The antenna produces notch at three frequency bands 3.25–3.65, 5.2–6.1 and 6.48–7.4 GHz, while yielding UWB performance from 3 to 15 GHz. The modal analysis of the antenna is carried out to investigate the notch band formation. The effect of rounded shaped slots in the patch and two C-shaped slots on both sides of microstrip feedline within the ground plane on the resonant modes is analyzed by observing current distribution in the patch and ground plane. It is observed that smaller round shape slot increases the input impedance of TM21 mode while larger round shape slot increases the input impedance of TM20 mode which yields band notch response.