Digital Tuner
A prototype software defined antenna was developed by Syntonics, a small U.S. company located in Columbia, Maryland working with researchers at the ElectroScience Laboratory of Ohio State University (B2 U.S. Patent 7,561,109 B2). This prototype SDA uses small movable pixel elements to selectively form reconfigurable microwave transmission lines and radiating patch elements. Under software control, changes to the size, shape, orientation and number of the radiating elements alter the frequency, polarization, gain and beam angle of the SDA based on external data input. Starting in 2004, the U.S. Department of Defense funded a series of feasibility and prototyping contracts to develop this SDA concept.
Measurements of this early prototype hardware, built with super sized pixels about 6 mm wide, have demonstrated tunable patch antenna structures operating at microwave frequencies. A pair of these patch elements was formed along with microstrip transmission lines to interconnect and feed the patches. Software defined variations in the feed lines created relative phase differences between the patches, thus steering the beam.
Large, conformal surfaces of this type could be easily reconfigured in near real time to provide beam steering of high gain antenna patterns. The ability to rapidly change frequency could also be advantageous for software defined radios that hop across large parts of the radio spectrum. SDAs could be used as multifunctional apertures connecting to different radios as the need arises.
It appears that one of the Scandinavia-based telecommunication companies is also working on an operational prototype.
Read more about this topic: Software Defined Antenna