The tremendous development of mobile networks has enabled ubiquitous communication. However, existing mobile networks are not designed to be "green". It is expected that the network energy consumption will triple by 2020, creating much higher CO2 emission. Given the threats of global climate change and the increased electricity price, it is highly desirable for future mobile networks to be more energy efficient. Equally important, the need for higher data rate mobile communication is ever increasing. The remarkable growth of high quality multimedia and social networks has pushed mobile data rates to the limit, and thus faster networks for the future are required. The group is part of the GreenTouch international consortium, which aims to improve the energy efficiency of communication network by 1000 folds. With funding from EPSRC, our projects specifically investigate into various techniques and system architecture to jointly optimise both energy and spectral efficiency that is suitable for future generation of communication networks.
5G Mobile Network
The latest Long Term Evolution (LTE) network substantially increases the data rate of mobile network, and the next version LTE-Advanced is expected in the next few years to support up to 1Gbps. However, with numerous inventions in smart devices and applications, the demand for higher data rate is ongoing. Research has already begun on the next generation of mobile network, the 5G. Although there is not yet any formal specification, it is anticipated that 5G can support an astounding 10Gbps per terminal. Apart from very wide bandwidth operation, novel techniques and mobile architecture will be needed to achieve this goal. The group is working on various approaches to tackle this challenge, including heterogeneous networks, millimeter wave communications, massive MIMO, cognitive radio, advanced multiple access techniques etc.
The rapid development in wireless communications has highlighted the need for much more efficient spectrum management schemes than what is being used today. However, several studies have shown that most of the spectrum, which is a limited natural resource, is underutilized for most of the time. Cognitive radio is a technology that aims to maximize the current usage of the licensed frequency spectrum by being able to adapt their communication parameters in order to operate within underutilized bands while avoid causing interference to the licensed users. Cognitive radio aims to provide services for license-exempt users by making use of dynamic spectrum access (DSA) and opportunistic sharing strategies (OSS). The group works on various aspects of cognitive radio, including spectrum sensing techniques, spectrum sharing approaches, and resource optimisation for cognitive radio network.