Optimum Design of Low-Cost Dual-Mode Beam- Steerable Arrays for Customer-Premises Equipment Applications

Two novel designs of dual-mode beam-steerable array antennas are proposed for customer- premises equipment applications. To obtain the optimal distribution of excitations for the arrays, the gain and front-back ratio of the array systems are optimized by using the method of maximum power transmission efficiency. The first design operates at 2.45 GHz and uses four folded monopoles of height<1/10 wavelength and a sleeve of height of 1/4 wavelength underneath the monopoles. The peak gain and the front-to-back ratio are 6.7 dBi and 7.8 dB respectively. The second design operates at 830MHz and uses four Yagi monopoles as elements with a common reflector and four directors. The peak gain and the front-to-back ratio for the second design are 6.0 dBi and 16.8 dB respectively. The proposed antennas have advantages including: low cost and compact size; dual-mode operation including the modes of omnidirectional radiation and directional radiation; and in the mode of directional radiation, the beam can be electronically steered to achieve the full coverage of the azimuthal plane. It achieves higher gain than the traditional electronically steerable passive array radiator antenna

Pattern reconfigurable, vertically polarized, low-profile, compact, near-field resonant parasitic antenna

© 1963-2012 IEEE. A vertically polarized, low-profile, compact, near-field resonant parasitic antenna with pattern reconfigurability is demonstrated. The antenna has three dynamic end-fire states facilitated with only three p-i-n diodes. The radiation pattern in each state covers more than 120° in its azimuth plane and, hence, it achieves beam scanning that covers the entire azimuth plane. The antenna height and transverse size are, respectively, only 0.048λ 0 and 0.1λ 02 . Measured results, in good agreement with their simulated values, demonstrate that the antenna exhibits a 11% fractional impedance bandwidth, and a 6.6 dBi peak realized gain in all three of its pattern-reconfigurable states. Stable and high peak realized gain values are realized over its entire operational band surrounding 2.22 GHz

Analysis and design of smart antenna arrays (SAAs) for improved directivity at GHz range for wireless communication systems.

Doctor of Philosophy in Electronic Engineering. University of KwaZulu-Natal, Durban 2018.Abstract available in PDF file