Efficient Resource Allocation and Paving the Way Towards Highly Efficient IMT-Advanced Systems

Recently, new network topologies including relays and meshed networks have emerged as a key technology receiving a lot of attention due to the increasing need for additional resources such as spectrum, and required high data-rates specified by the International Mobile Telecommunication-Advanced (IMT-Advanced) systems (Report ITU-R M.1645, Framework and overall objectives of the future development of IMT-2000 and systems beyond IMT-2000). These systems are designed to provide diverse services sustaining low to high mobility applications and yielding a significant improvement in terms of Quality-of-Service (QoS). In this paper, we identify and describe the novel network topologies that will be able to accommodate the high data rates demanded within the spectrum scarcity paradigm. By efficiently integrating mesh networks and flexible resource sharing, the overall network efficiency is shown to increase. In addition, direct terminal-to-terminal (T2T) communication both with and without the use of relays is presented, where terminals communicate without the use of base stations (BSs) as it is done in conventional systems. The results show significant gains in terms of throughput, average frame delays and power consumption compared to conventional networks. Finally, open issues and potential challenges are addressed.