Resumen
Future radio systems, such as software defined radio and cognitive radio concepts give rise to significant challenges for antenna design and in particular reconfigurable antenna design. Whilst there are many possible ways in which such systems could be configured, this paper discusses some of the range of possible antenna requirements, and some design approaches are outlined. Demonstrator antennas are described. Results for three antennas, suitable for small and medium sized terminals, are given, in which integration into a single antenna of wideband and narrowband functionality, necessary for search and operation respectively, is achieved. The design of an array with band switching, which may be useful in system base stations that require both spatial and spectral discrimination, is also discussed.
