Cooperative Communications in Machine to Machine (M2M): Solutions, Challenges and Future Work

The application of cooperative communication (CC) in wireless networks makes it possible for the terminals to hear and aid the transfer of each other's information to the required destinations. CC utilizes the advantage of the broadcast nature of wireless communications to achieve its objectives. The advantages enjoyed by networks that employ the principles of CC include: improvement of connectivity, improvement in energy utilization, spectrum efficiency, counteracting of the limited per device complexity, and a boost in communication reliability among devices in the network. When CC is compared with other techniques that perform functions similar to it like multiple input multiple output, it has an upper hand due to the fact that CC has a hardware that is feasible and its deployment is more flexible. The implementation of CC in machine to machine (M2M) in this paper is based on the use of relays and clustering protocols. Popular protocols of relays and clustering are presented as solutions, and detailed emerging research challenges that include but are not limited to: escalating complex scheduling design, increased message overheads, increased intra and inter network interferences, increased end-to-end latency, and redundancy are discussed. Future works that includes critical application of full duplex relays, utilization of non-regenerative mode of relay operation, cross layer optimization, application of clustering scheme with reconciling quality-of-service properties, and designing of hybrid clustering techniques are proposed. They are aimed at improving on the challenges and hence foster efficiency in M2M network resources.