Comparison of Differential Space-Time Block Codes and Differential Cyclic Delay Diversity for a Multi-carrier Wireless System

Differential transmit diversity is an attractive alternative to its coherent counterpart, especially for multiple antenna systems where channel estimation is more difficult to attain compared to that of single antenna systems. In this paper we compare two different types of differential transmit diversity techniques for a multi-carrier based transmissions in particular OFDM. The first technique uses Differential Space-time Block Codes from orthogonal designs and the second uses Differential Cyclic Delay Diversity. The results present the bit error performance for several transmit antenna configurations. The results show that DCDD offers close performance to that of DSTBC with the advantage of simplified receiver.