Special issue on cooperative wireless and mobile communications

Abstract

The fundamental idea of cooperative communications in wireless networks originates from the design of multiple-antenna systems. In multiple-antenna systems, communicating terminals are equipped with multiple antennas to mitigate the effects of multipath fading and optimise the communication rate in the network. Wireless communication nodes like cellular phones and sensor nodes have size restrictions, power supply limitations and are only able to accommodate a limited level of complexity. It is thus unfeasible to equip them with multiple antennas. The effects of multipath fading are critical in cellular, ad hoc and sensor networks because the physical deployment of communicating nodes makes them susceptible to interference. It is imperative to adopt a mechanism to combat fading in such networks. The broadcast nature of the wireless medium makes it easy for the communicating nodes to hear each other. They can share their physical resources specifically their single antennas, thereby creating a virtual multiple-antenna array. Cooperative communications is a concept where several single-antenna nodes cooperate and form a distributed multiple-antenna system which combats multipath fading. In recent years, cooperative communications have received extensive world-wide attention and significant advances in both research and applications have been achieved. The aim of this Special Issue is to publish research papers reflecting the most recent research and application results in cooperative wireless and mobile communications and networks, with emphasis on the physical layer challenges of virtual and distributed multiple-input–multiple-output (MIMO). A good number of submissions have been received. After a rigorous review, 12 papers have been selected for publication in the Special Issue. These papers are, respectively, concerned with randomised distributed space–time coding schemes, full-rate alternate-relaying cooperative systems with simplified detectors, adaptive transmission techniques for cooperative networks with limited feedback, cooperative MC-CDMA downlink transmission with preprocessing, capacity of generalised network MIMO with multicell cooperation, joint and distributed scheduling with power control in mulitcell OFDMA networks, relay selection strategies for two-way mobile relaying networks with analogue network coding protocol, multiple-source multiple-destination relay channels with network coding, cooperative spectrum sensing with hidden Markov models, cognitive relay networks with relay selection, cooperative communication between cognitive and primary users and optimal incentive collaborative primary-secondary transmission. These topics can be broadly classified into the following four directions: development of more general and practical models of cooperative communications (papers 1–4), research of multicell networks with cooperative communications (papers 5 and 6), fusion of cooperative diversity and network coding (papers 7 and 8) and combination of cooperative communications and cognitive radio (papers 9–12). As one of the most important enabling technologies of recent time, cooperative communication techniques will play a crucial role in the development of 5G wireless and mobile networks and receive continued focus of research from world-wide academia and industry. We are grateful to all the authors of the papers for their contribution to the Special Issue. We would also like to thank all the reviewers of the papers for their careful and valuable comments. Assistance from the editorial staff at the IET is much appreciated. Finally, support from Sherman Shen, Editor-in-Chief of IET Communications and Kruna Vukmirovic, IET Journal Development Editor is highly acknowledged.