Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

We are living through a revolution, as electronic communications become ever more ubiquitous in our daily lives. The use of mobile and smart phone technology is becoming increasingly universal, with applications beyond voice communications including access to social and business data, entertainment through live and more immersive video streaming and distributed processing and storage of information through high performance data centres and the cloud. All of this needs to be achieved with high levels of reliability, flexibility and at low cost, and solutions need to integrate developments in theoretical algorithms, optimization of software and ongoing advances in hardware performance. These trends will continue to shape our future. By 2020 it is predicted that the number of network-connected devices will reach 1000 times the world's population: there will be 7 trillion connected devices for 7 billion people. This will result in 1.3 zettabytes of global internet traffic by 2016 (with over 80% of this being due to video), requiring a 27% increase in energy consumption by telecommunications networks. The UK's excellence in communications has been a focal point for inward investment for many years - already this sector has a value of £82Bn a year to the UK economy (~5.7% GDP). However this strength is threatened by an age imbalance in the workforce and a shortage of highly skilled researchers. Our CDT will bridge this skills gap, by training the next generation of researchers, who can ensure that the UK remains at the heart of the worldwide communications industry, providing a much needed growth dividend for our economy. It will be guided by the commercial imperatives from our industry partners, and motivated by application drivers in future cities, transport, e-health, homeland security and entertainment. The expansion of the UK internet business is fuelled by innovative product development in optical transport mechanisms, wireless enabled technologies and efficient data representations. It is thus essential that communications practitioners of the future have an overall system perspective, bridging the gaps between hardware and software, wireless and wired communications, and application drivers and network constraints. While communications technology is the enabler, it is humans that are the producers, consumers and beneficiaries in terms of its broader applications. Our programme will thus focus on the challenges within and the interactions between the key domains of People, Power and Performance. Over three cohorts, the new CDT will build on Bristol's core expertise in Efficient Systems and Enabling Technologies to engineer novel solutions, offering enhanced performance, lower cost and reduced environmental impact. We will train our students in the mathematical fundamentals which underpin modern communication systems and deliver both human and technological solutions for the communication systems landscape of the future. In summary, Future Communications 2 will produce a new type of PhD graduate: one who is intellectually leading, creative, mathematically rigorous and who understands the commercial implications of his or her work - people who are the future technical leaders in the sector.

Electronically beam-steerable array antennas (phased arrays or smart antennas) at microwave and millimetre-wave (mm-wave) frequencies are extremely important for various wireless systems including satellite communications, terrestrial mobile communications, radars, "Internet Of Things", wireless power transmission, satellite navigations and deep-space communication. Traditionally, beam steering of antenna is achieved by moving the reflector mechanically, which is slow, bulky and not reliable. Phased arrays, which integrate antennas and phase shifter circuits, are an attractive alternative to gimbaled parabolic reflectors as they offer rapid beam steering towards the desired targets and better reliability. Phase shifters are critical components in phased arrays as the beam steering is achieved by controlling phase shifters electronically. A promising research direction to create small, fast, reliable phase shifters with low insertion loss at high frequency is the use of tunable dielectric materials due to its potential of monolithic fabrication of array antennas and circuits. A breakthrough in such materials came recently when we demonstrated that Lead Niobate Pyrochlores PbnNb2O5+n gives the best combination of dielectric constant, tunability and low loss of any known thin film system. Translating these superior materials properties into actual device performance and high-performance electronically beam-steerable arrays antennas at microwave and mm-wave bands are the key aims of this project

In response to the growing demands for delivery of content-rich and delay-sensitive services, network architectures for 5th generation and beyond wireless communication systems are becoming more and more dense. This illustrated through the ever increasing deployment of small cell networks as well as machine-to-machine (M2M) communications. This trend, whilst improving network capacity, will still necessitate reuse of available resources such as frequency spectrum within smaller areas by larger number of nodes/cells, which in turn would adversely affect the quality of service. On the other hand, by allowing simultaneous transmission and reception in the same frequency band, In-band Full-Duplex Communication (IFDC) technology potentially enhances the spectral efficiency of a single point-to-point (P2P) channel by 100% over the conventional half-duplex communication. IFDC also enables the nodes, e.g. in P2P scenarios, to receive channel feedback or sense other channels whilst transmitting data, which shortens the latency compared to conventional half duplex communication with time-division-duplexing. Moreover, using full duplex relay nodes in multi-hop scenarios can potentially reduce the end-to-end latency by enabling simultaneous receiving and relaying. Practical implementation of this technology requires rigorous interference cancellation methods at each node to suppress the strong self-interference imposed on the receiver by the transmitter of the same node. The major bulk of research on IFDC has focused on self interference cancellation (SIC), and the respective state-of-the-art technology can achieve a high level of SIC at full duplex terminals; hence the IFDC technology has become closer to commercial deployment by industry. Deploying IFDC in realistic dense settings entails new range of technical challenges, and opportunities alike. IFDC can yield substantially greater network throughputs and delay reductions over half duplex networking by deploying the technology in denser networks. However, attaining such gains demands for efficient scalable resource allocation and multi-node interference control methods. This great potential of 'full-duplex dense networks' in 'scalable service provisioning' has not been addressed to date by the research community in sufficient depth. At physical-layer, new resource allocation challenges arise in IFDC networks; for instance, in the design of concurrent channel sensing and data transmission, and in adapting transmit power of the nodes to their variable self-interference. Also, using IFDC in dense scenarios will affect design of the protocols in the higher layers; for instance IFDC would entail greater chance of packet collisions and multi-node interference, which demands for new medium access control (MAC) protocols suited to the emerging dense full duplex networks. Furthermore, IFDC will enable full duplex relaying in multi-hop communication, hence requires new Forwarding-layer/Network-layer protocols to deal with the new full-duplex forwarding paradigms. For conventional half duplex scenarios it is known that network throughput and quality of services can be improved through cross-layer methods, particularly with co-design of physical and MAC layers or MAC and Network/Forwarding layers. In fact for optimal scalability of heterogeneous services in full duplex dense networks, cross-layer approaches are inevitable. This project aims to propose systematic design of resource allocation and interference suppression techniques and algorithms at physical, MAC and Forwarding layers in order to enable substantial throughput gain and delay reduction by deploying full-duplex communication in dense wireless networks. These new methods will pave the way for deploying scalable service provisioning in the emerging dense wireless networks.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.