Distributed interleave-division-multiplexing space-frequency-codes

Abstract

This paper proposes the application of Interleave-Division Multiplexing (IDM) to an OFDM-based radio access in relay-networks. In the proposed scheme, the relay-specific interleaving is performed on subcarriers in the frequency domain, which we call IDM Space-Frequency Code (IDM-SFC). IDM-SFC in combination with OFDM radio access is well-suited for distributed deployment of relays, as it is robust to the multi-path interference and it can achieve full spatial diversity with a constant rate of 1 on the relay-destination hop irrespective of the number of parallel relay nodes. It will be shown that IDM-SFC outperforms other promising distributed diversity schemes like OFDM with Cyclic Delay Diversity (CDD) significantly in various scenarios. In addition to Frame Error Rate (FER) analysis, also more theoretical considerations are carried out with the help of Extrinsic Information Transfer (EXIT) Charts giving a better insight into the different approaches.