BROADBAND DIPOLE ANTENNA WITH INTEGRATED BALUN FOR ENHANCED WIDEBAND AND STABLE COMMUNICATION PERFORMANCE

Abstract

Broadband wireless communication systems require antennas with wide impedance bandwidth, stable radiation characteristics, high efficiency, and compact structural integration to support reliable multi-band operation. This paper presents the design, optimization, fabrication, and experimental validation of a broadband dipole antenna incorporating an integrated balun to enhance impedance matching, radiation efficiency, and communication stability. The antenna geometry was developed using full-wave electromagnetic modelling and optimized through parametric analysis before prototype fabrication and experimental characterization using a calibrated vector network analyzer. The fabricated antenna achieved a measured operating frequency range of 1.18 - 4.43 GHz, corresponding to an impedance bandwidth of 3.25 GHz and a fractional bandwidth of 113.8%. A minimum reflection coefficient (S₁₁) of -36.8 dB and a VSWR of 1.11 were obtained, demonstrating excellent impedance matching throughout the operating band. The antenna further achieved a measured peak gain of 7.6 dBi, radiation efficiency of 94.5%, and stable radiation patterns across the entire frequency range. Comparative analysis with a conventional dipole antenna revealed bandwidth, gain, and radiation-efficiency improvements of 264.1%, 83.7%, and 13.7%, respectively. Furthermore, the maximum deviation between simulated and measured results remained below 6%, confirming the validity of the proposed electromagnetic model and fabrication process. The integrated balun effectively suppresses common-mode currents, improves current symmetry, and enhances overall antenna performance, demonstrating the proposed design as a robust solution for broadband and stable wireless communication applications.