Low-Return-Loss Printed Log-Periodic Dipole Antenna

In this letter, a low-return-loss printed log-periodic dipole antenna (PLPDA) fed by a coaxial cable is presented. The widths of dipole elements are optimized to increase the bandwidth. A study of coaxial cable position is included in order to improve the antenna behavior. The measured return loss is lower than -15 dB from 2.1 to 4.3 GHz. The measured gain varies between 6 and 7 dBi. The measurements, including input impedance, gain and radiation patterns, and simulations are in agreement.