Cyclic Delay Diversity: Effective Channel Properties and Applications

Abstract

We briefly explain the concept of cyclic delay diversity (CDD) as a variant of standard conformable delay diversity techniques. Usually being implemented at the transmitter side of an OFDM based system, the application of CDD is recognized at the receiver side only by observing modified channel propagation conditions. Therefore, we analyze the effect of CDD on the channel fading properties observed by a receiver in terms of the effective channel transfer function and the effective subcarrier fading correlation function. These modified properties provide the possibility for optimizing diversity and coding gain of mobile radio communications systems. Simulations show the performance improvement capabilities of CDD for the terrestrial digital video broadcasting system (DVB-T) and to a cellular mobile radio communications system.