Size-reduced printed log-periodic dipole antenna for wireless communication applications

Abstract

In this study it is proposed a printed log-periodic dipole antenna (LPDA) for wireless communication applications which consists of dipoles having reduced dimensions by using first order semicircle structures. The bandwidth is increased by adding small rectangular patches to initial part of antenna feed line and putting slots to the end. A size reduction of about 14% is obtained in the proposed antenna in comparison with the standard printed LPDA with the usage of semicircle structures. In addition to size reduction while semicircle structures also increase the upper band of the antenna operating frequency to 2.5 GHz to cover wireless communication frequencies of Bluetooth and 2.4 GHz Wi-Fi rectangular slot decreases to the lower band to around 0.86 GHz to include RFID and GSM 900 frequencies. According to measurement results of the manufactured structure the antenna is observed to have return loss better than 10 dB a quite stable/low variation gain as 4.75 dBi +/- 0.75 dBi and compact size as compared to similar studies in literature at a wideband operating frequency of 0.86 GHz and 2.5 GHz which can be used in several wireless communication systems.