Enhanced Iterative-Based ZP-OFDM Receiver in Multi-Relay Cooperative Networks

Zero-Padding Orthogonal Frequency Division Multiplexing (ZP-OFDM) has recently been introduced to avoid coded-OFDM's high decoding complexity. Various sub-optimal ZP-OFDM receivers have been developed in the literature to tradeoff performance with implementation complexity. In this paper, the authors propose a new iterative detection scheme for ZP-OFDM transmissions tailored to broadband cooperative networks with multiple relays and amplify-and-forward relaying. By avoiding channel dependent matrix inversion, which is inevitable in the case of Minimum Mean Square Error (MMSE)-ZP-OFDM transmissions, and incorporating linear processing techniques, they show that their proposed Low-Complexity MMSE-ZP-OFDM (LC-MMSE-ZP-OFDM) receiver is able to bring significant complexity reduction in the receiver design, while outperforming cooperative MMSE-ZP-OFDM.