A software defined testbed for reconfigurable antenna cognitive radio

A cognitive radio is capable of sensing local radio conditions and adapting its transmission and reception parameters to optimize performance in the evolving network environment. The use of software defined radio (SDR) to make communications more flexible has greatly facilitated the design of cognitive radios, by making communications reconfigurable at lower layers of the networking stack. The Cognitive Antenna Testbed described in this paper augments the flexibility of physical layer design through the use of reconfigurable antennas, which are capable of adapting frequency, pattern and polarization electrically, thereby expanding the design space of cognitive radio and networking algorithms. This testbed offers a platform for developing and field-testing reconfigurable antenna algorithms. Representative results of experiments performed with this testbed for antenna state selection, are provided to illustrate its relevance to cognitive networking research. Current research adapting this technology for use in dynamic spectrum access (DSA) applications is also discussed.