EFFECTIVE IMPLEMENTATION TECHNIQUES OF RECONFIGURABLE ANTENNAS FOR COGNITIVE RADIO ENVIRONMENTS
D.M.K. Chaitanya, N. V. Koteswara Rao · IJITR International Journal of Innovative Technology and Research - IJITR International Journal of Innovative Technology and Research · 2015
: The growing demand for the wireless connectivity has insisted a new communication technique to exploit the usage of spectrum in an efficient way. Cognitive Radio has been introduced as a resource for the effective usage of the spectrum by means of exploiting existence of spectrum holes. The notion of Reconfigurability has turn into an essential aspect of recent, radio-frequency, agile systems for wireless as well as space communications. Reconfigurable antennas are necessary to cover various wireless services that are spanned on extensive frequency range and they have multi-functional properties like sensing the spectrum and communicate at a stretch, hence are better suited for the Cognitive Radio (CR) environments. This paper explains the basic concepts, effective design and implementation techniques of various types of reconfigurable antennas, methods of Reconfigurability along with their applications. The Reconfigurability can be achieved either in terms of frequency, radiation pattern or polarization by implementing suitable switching mechanism. The switching methods in the design of reconfigurable antenna for cognitive radio environments have been presented. Reconfigurability of the antenna have made the Cognitive Radio so popular as it conveniently utilizes the unused spectrum both for sensing and communicating without disturbing the licensed users.