Wideband four arm log-periodic planar antenna with Wi-Fi band rejection

Abstract

The log-periodic antennas (LP), also know as a log-periodic array or log-periodic aerial which are very effectively useful to achieve large bandwidth. By careful design of planar log-periodic antennas with impedance matching we get large bandwidth. The chebyshev impedance matching is one of the best techniques to produce large bandwidth in log-periodic antenna. In this paper four arm log-periodic antenna is designed for the both linear and circular polarization. When the 900 phase delay applied between the two dipoles the antenna produce circular polarization. The antenna is operated at 3GHz gives the band of operation from 2GHz band upto K/Ka band. According to IEEE 802.11 the 5.1GHz to 5.8GHz band is occupied for Wi-Fi applications. So there is a need to eliminate the Wi-Fi band by using integrating filter method. The antenna is designed and simulated by using HFSS software, the variation of voltage standing wave ratio(VSWR), return loss and axial ratio plots are generated from 2GHz to 18GHz. The antenna is fabricated on FR 4 substrate for band rejection by using integrating filter method. Measured results are well accepted with simulated results.