  In this paper we present a survey of existing prototypes dedicated to
software defined radio. We propose a classification related to the
architectural organization of the pro- totypes and provide some conclusions
about the most promising architectures. This study should be useful for
cognitive radio testbed designers who have to choose between many possible
computing platforms. We also introduce a new cognitive radio testbed currently
under construction and explain how this study have influenced the test-bed
designers choices.
