Bandwidth Efficient Space-Frequency Codes Based on Cyclic Delay Diversity

Cyclic delay diversity (CDD) is a simple and effective approach to exploit transmit diversity by increasing the channel frequency selectivity (diversity) in a multiple-input multiple- output (MIMO) OFDM system. The increased frequency diversity can then be exploited by concatenating some error control code, e.g. convolutional code, at the expense of spectral efficiency. In this paper, we study the pairwise error probability (PEP) of CDD, which motivates us to propose a new space-frequency coding (SFC) framework based on CDD. The proposed SFC scheme can achieve full spatial and frequency diversity, but, without sacrificing spectral efficiency.