Quasi-Yagi Antennas Using Log-Periodic Dipole for Multi-Band Wireless Applications

This paper introduces log periodic dipole antenna based quasi-Yagi antennas that are well-suited for advanced multi-band wireless applications. The examined antennas in this study are fed by means of a coaxial feed. Impedance matching was achieved through utilization of an impedance transformer (balance to unbalance). The antennas discussed herein, labeled as antennas 1 and 2, provide a total of four and five operational bands, respectively. The first antenna exhibits resonance frequencies at 2.11 GHz, 5.4 GHz, 6.55 GHz, and 8.55 GHz. The related values for gain, bandwidth, and FBR (front-to-back ratio) at these resonances are (5 dB, 3.7 dB, 2.6 dB, and 3.3 dB), (42.6%, 14.8%, 7.63%, and 22.22%) and (10 dB, 5.5 dB, 7 dB, and 5.5 dB), respectively. Similarly, the second antenna showcases resonant frequencies positioned at 1.795 GHz, 2.54 GHz, 3.835 GHz, 5.1 GHz, and 7.11 GHz. At these resonances, gain, bandwidth, and FBR (front-to-back ratio) are (5.61 dB, 4.91 dB, 4.48 dB, 3.25 dB, and 2.44 dB), (8.35%, 36.2%, 2.0%, 20.2%, and 7.59%), and (20.30 dB, 13.83 dB, 10.22 dB, 14.59 dB, and 14 dB), respectively. Given these values, the aforementioned antennas prove to be beneficial for WLAN, and 6 GHz (5.925–7.125 GHz) Wi-Fi applications, and 4G-LTE bands 3, 7, 16, 46, and 84. Finally, the measured data was compared with the analytical data for validation of the proposed antennas.