Design of broadband ESPAR antenna using inverted F monopoles

A low-cost, low-power smart antenna with broad bandwidth is presented in this paper. To achieve the beamforming, the structure of an electronically steerable parasitic array radiator (ESPAR) is adopted. The proposed ESPAR antenna comprises of a monocone antenna as the driven element at the center of the ground plane surrounded by six inverted F monoples antennas (IFAs) as parasitic elements. IFA antennas are employed for reducing the size and cost of antenna. To realize electronic beam steering, six PIN diodes are loaded at the bottom of the parasitic elements. By switching the PIN diodes, the antenna main beam can be steered in the horizontal plane across a range from 0° from 360°. The main aspects of antenna implementation are interpreted and the simulations results obtained from electromagnetic (EM) field simulation software are presented and discussed.