Modal Analysis of Triple Band Notch Ultra-Wideband Antenna with three C-shaped slots

A compact ultra-wideband antenna with triple band notch function is investigated. The antenna exhibits UWB performance from 3-12 GHz but notch responses are present at three frequency bands 3.2–3.8, 4.05–4.45, and 5.1–5.9 GHz. The investigation of modal analysis of the antenna with the support of current distribution for the notch bands formation. The effect of C-shaped slots incorporated in the patch on the resonant modes is examined by observing current distribution existing within the patch. It is experiential that the outer C-shaped slot placed in lower part of hexagon increases the impedance of TM 21 mode while upper C-shaped slot rises the impedance of degenerated TM 02 mode which consequences band inotch characteristics. The analysis of antenna in time-domain indicates notable group delay in the notch bands.