Spectrally efficient error free relay forwarding in cooperative multihop networks

Multihop cooperative communication is emerging as a key concept to extend the coverage area and potentially increase the capacity of wireless networks. With multiple hops, processing at the forwarding nodes is a major source of error propagation. In this context, a novel spectrally efficient transmission scheme with error protection for such networks is proposed in this paper. The proposed scheme retains the spatial diversity and enhances the bandwidth efficiency by integrating incremental redundancy concepts into such cooperative multihop systems. The guard against error propagation and the overhead for coordination among multiple nodes in such networks is mitigated by the implicit feedback channel available due to broadcast nature of wireless transmissions. The proposed scheme fully leverages the benefit of overhearing and eliminates the additional feedback slots required for validation. Further, it ensures reliable forwarding of information which optimizes the throughput of multihop networks. Theoretical framework is also developed for the proposed system and supported with results from extensive simulation studies.