Wideband Microstrip Yagi-Uda Array Antenna with High Gain and F/B Ratio for 5 GHz Wi-Fi Band Applications

摘要

A wideband inset feed microstrip Yagi-Uda array antenna on photonic crystal substrate with high gain and front to back (F/B) ratio for 5 GHz Wi-Fi band has been proposed. At first, a microstrip Yagi-Uda array antenna has been designed on Rogers RT/Duroid 5880 (lossy) having dielectric constant of 2.2 and tangent loss of 0.0009. Later on, few numbers of cylindrical air gaps has been introduced in the substrate and the length and width of patch somewhat has been readjusted without changing overall size of the antenna. In that case the performance of the antenna is enhanced in terms of IEEE gain (9.816 dB), directivity (10.15 dBi), bandwidth (396.2 MHz), efficiency (96.71%) and F/B ratio (29.094 dB) though return loss somewhat decreases. So the proposed antenna possesses very high front to back ratio as well as high gain and wide bandwidth. A vivid comparison between the microstrip Yagi-Uda array antennas without air gaps and with air gaps have also been presented in this paper.