Ultra-Broadband Omnidirectional Printed Dipole Arrays

S. Sevskiy, W. Wiesbeck, 2005 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Washington DC, USA, July 2005.

Abstract

This paper presents a novel antenna concept based on a combination of the logarithmic-periodic antenna with the loop antenna. This concept allows realization of very broadband antennas with unique radiation properties - omnidirectional radiation pattern and horizontal polarization. The antenna concept is derived from a small loop antenna by replacing the wire of the loop by small dipoles arranged on a circumference and fed in phase along the circumference. This small dipole structure is then extended to antenna structures with halfwavelength dipoles incorporating different feeding techniques. The logarithmicperiodic
principle is then applied to attain ultra-broadband radiation properties. The obtained antenna designs can be used alone or in combination with a vertically polarized antenna as a multi-band indoor base station antenna with horizontally polarized or dual-polarized omnidirectional radiation patterns.