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This paper presents initial experiences with the design and implementation of a low-cost beam steering antenna for long-distance WIFI applications. The antenna system has three components: (1) an adaptive parabolic reflector constructed from an array of passive scatterers with tunable reactive loads, (2) an optimizer that runs on a host computer that adjusts the phases and amplitudes of their currents based on received signal strengths, and (3) a minimal hardware controller that interfaces to an array of digital-to-analog converters and varactor bias voltage logic. Experimental measurements confirm electrodynamics simulations and show that highly directional patterns can be realized while controlling orientation in azimuth and elevation. Initial results achieve 18 dBi of gain across an operational 50 degrees of azimuth with a beam width of 10 degrees. Higher gains of 22 dBi or more are possible with reduced range of steerability.

We present the results of studying experimentally a constructively simple and inexpensive centimeter-wave antenna having a radiation pattern, whose shape can be controlled. Specifically, the main lobe of the pattern can be scanned in a wide angular range, its width can be changed, and minima of the pattern can be formed in specified directions. The feed being the only active element of the antenna is located in front of the mirror made up by a system of steerable passive scatterers, which are dipole antennas loaded by semiconducting diodes. The capacity of the diode loads is changed under the action of controlling signals, which set specific bias voltages at each diode. The studies aimed at testing experimentally the operability of the antenna and assessing the practically achievable parameters of the proposed antenna design. The developed laboratory model of the antenna operates at frequencies near 2.4 GHz with a gain of more than 21 dBi and the possibility of scanning the main lobe of the radiation pattern in the horizontal and vertical planes to ±60 • and ±15 • , respectively, for the antenna with overall dimensions 100 × 60 × 30 cm.