Slit Loaded Circular Ultra Wideband Antenna for Band Notch Characteristics

This paper proposed a planar, low cost, simple, and compact printed microstrip-fed circular monopole ultrawideband antennas with band-notched characteristics. By introducing pair of open slits and varying angular separation between slits on the circular patch the band notched characteristics can be obtained. The proposed antennas are successfully simulated, designed, fabricated on FR-4 substrate. The measured results show that the proposed antenna with dimensions of $\pmb{65\mathrm{mm}\times 65\mathrm{ mm} \times 1.6\mathrm{mm}}$ has a bandwidth over the frequency band 2.00-10.6 GHz with $\mathbf{VSWR} \pmb{\leq 2}$ , except 2.5-3.95GHz with circular antenna having pair of slits. The presented antennas shows nearly omnidirectional radiation pattern, stable gain, small group delay variation at working frequencies. Satisfactory results have been obtained in frequency and time-domain analysis of the proposed structure.