PERFORMANCE ANALYSIS OF THE STFC FOR COOPERATIVE ZP-OFDM : DIVERSITY , CAPACITY , AND COMPLEXITY

In this paper, we consider a cooperative Zero-padding orthogonal frequency division multiplexing (ZP-ODFM) communication with multiple carrier frequency offsets (CFOs) and multipath channel, and propose a space time frequency coding (STFC) scheme to exploit the linear convolutional structure of the ZP-OFDM. Theoretical analysis of the proposed STFC is provided based on the analytical upper bound of the channel orthogonality deficiency. To reduce the system complexity, low-complexity linear equalizers, such as zero-forcing (ZF) and minimum mean square error (MMSE) equalizers are often adopted. We also show that with only linear receivers, the proposed code achieves the full cooperative diversity and improves the system capacity.