Wideband omnidirectional radiation linearly polarized antenna for UHF and DTV applications

Abstract

An innovative wideband omnidirectional linearly polarized antenna is presented in this paper that is specially designed for Ultra-High Frequency (UHF) applications, with a particular focus on Digital Television (DTV) broadcasting. The proposed antenna operates across a frequency range of 479–808 MHz, ensuring sufficient coverage for DTV applications. Key design features include the use of four-paired crossed-dipole antennas, encircling parasitic elements, and concentric circular circles on an FR4 substrate to enhance impedance bandwidth and gain. The fabricated antenna demonstrates a measured reflection coefficient better than -15 dB over the critical 550–750 MHz frequency band, achieving a peak gain of 0.90–1.35 dBi with stable performance across its operational spectrum. Its omnidirectional radiation pattern, characterized by a 360° $E$-plane and 121.2° $H$-plane Half Power Beam Width (HPBW), makes it ideal for uniform signal coverage in DTV broadcasting. The design prioritizes compactness with dimensions of 0.56$\lambda \times 0.56\lambda \times 0.005\lambda$, meeting space constraints for practical deployment. Detailed simulations and experimental validation demonstrate the antenna’s effectiveness in achieving its design objectives. This work advances wideband UHF antenna technology, offering a reliable and cost-effective solution for industrial broadcasting applications. The proposed design is optimized for manufacturability, ensuring compatibility with high-volume production.