The Northumbria Communications Research Lab is a multidisciplinary research group with fundamental as well as applied research interests. The NCRLab research is focused on in the following areas:
Photonic Communications: The research is focused on devices, and systems for high-speed optical switching, optical routing and buffering, and free space optics. Much of the work is fundamental in nature involving mathematical and computer modelling and practical implementation, in collaboration with national and international partners. Current projects include:
• Free space optical (FSO) communications: To investigate (theoretically and experimentally) techniques of mitigating atmospheric effect on laser beams. A 4-beam FSO experimental link currently instated between two research laboratories based in Northumbria and Newcastle Universities will be used to test multiple sub-carrier modulation schemes with spatial diversity, coding channel equalisation under weak and strong turbulence as well as scattering and absorption due to fog, rain, and aerosol.
• Modelling, simulation and implementation of novel all-optical packet switching routers based on PPM format for high-speed (> 80 Gb/s) for single wavelength and WDM networks. Using PPM the routing table size is reduced significantly, thus leading to a much faster packet header address correlation.
• New receiver design based on the wavelet transform (for feature extraction) and artificial neural network (for pattern classification) for optical wireless communications. This work involves combining the detection, equalization and decoding problem as a single classification problem and use single ANN for all the purposes.
• Application of orthogonal frequency division multiplexing (OFDM) for indoor optical communication links. This involves mathematical modelling, computer simulations, design and implementation.
• Visible Light Communications
• Radio over Fibre communications
• Chaos communications where the research focus is on applying chaotic synchronisation in secure communication links to recover the message with high efficiency and accuracy. This research is investigating new design of modulation techniques, equalisation, decoding and high performance observer
People: Professor Z Ghassemlooy, Dr Wai Pang Ng, Dr Hoa Le-Minh
Web site: http://soe.northumbria.ac.uk/ocr/
In this area design, simulation, numerical modelling and experimental verifications have been carried out on
novel broadband RF/microwave printed antennas
integration of broadband circularly-polarized antenna with broadband high-efficiency class-E power amplifier at 2 GHz suitable for mobile communications
designs of high-efficiency RF/microwave power amplifiers in class E and class F modes for mobile communications
use of genetic algorithms for design optimisation and direct integration of high efficiency amplifiers with antennas
antenna measuring techniques
near field antenna measurements
Linear and Circular Polarised Active
Integrated Antenna: High Efficiency Class-F and Class-F-1 Amplifiers High
efficiency Class-F and Class-F-1 amplifiers with reduced power dissipation in
device are investigated theoretically and experimentally. The Genetic Algorithm is used for design optimisation.
People: Professor A Sambell, Professor D Smith, Dr M Elesdon
Microwave Holographic Imaging: This work focuses on the use of phaseless holographic techniques for antenna measurements and imaging. By using a patented indirect holographic measurement technique this group have been able to reconstruct 3D images from single 2D intensity patterns. This has enabled us to develop low cost techniques for the near field testing of antennas and for the reconstruction of antenna aperture fields. This work has also been extended to the detection and imaging of concealed weapons where the ability to reconstruct phase patterns offers advantages in the detection of concealed explosives and to the area of medical imaging. In this area the group are working in collaboration with medical staff at Newcastle University Medical School in developing these techniques to aid breast cancer detection and imaging.
Smart Antenna: This group are also active in
the areas of developing terminals for mobile satellite communications and in the
development of smart antennas for mobile communication systems.
People: Professor D Smith
Non-linear Control & Applications
The design of controllers and observers for general nonlinear dynamical systems: This is a difficult problem and there is no general methodology to tackle such problems. In many instances, one can only design observers and controller for classes of nonlinear systems. The NCRLab is mainly concerned with the design of observer/controller for particular classes of nonlinear systems with application to bioreactors, power systems, helicopter control and chaotic communication. With regards to bioreactors, the main focus is its application to modern biological wastewater treatment plants. A number of original observer design methodologies for the estimation of biomass concentration and the specific growth rate are proposed.
Estimation of power coefficient in wind energy conversion systems. This research is mainly carried out in collaboration with members of the Energy Systems Group. The NCRLab has recently acquired a laboratory helicopter on which various types of control strategies are implemented, tested and compared. Finally, the problem of designing nonlinear observers for chaotic systems is investigated so as to implement a chaotic based communication system.
Control and estimation - mathematical modeling and analysis; The NCRLab is mainly concerned with the design of observer/controller for particular classes of nonlinear systems with feedback control design, digital control, observer design for linear and nonlinear systems; parameter identification; model-based fault detection and diagnosis, with application to:
• power systems: flux estimation in induction machines, excitation control for synchronous generators, mid-voltage and power control using ASVC, control of wind energy conversion system.
• chemical and biotechnological processes: kinetic rates estimation in bioreactors, composition control and components faults diagnosis in CSTRs.
• mechanical systems: control of flexible joint and rigid robots.
• automotive systems: engine modeling and EGR control.
• digital signal processing and secure communications: Non-uniform sampling, communication using chaotic carriers, chaotic synchronisation
The underlying principles of control and how they can be used to develop, from a strong theoretical foundation, practical design methods for practising control engineers is the mean focus of research in:
Theoretical contributions to the field of robust multivariable control
Application of advanced control system design to engineering systems
People: Dr K Busawon, Professor I Postlethwaite
Advanced Signal Processing
ltra High Energy Neutrinos: The NCRLab is involved in the ACoRNE project on ultra high energy neutrinos using the thermoacoustic mechanism in seawater in collaboration with University College London, Imperial College, Sheffield, and Lancaster. The project (£287k) is jointly funded by MoD and PPARC. The experimental work is based at the Rona naval hydrophone array in Scotland and the acoustic signals are analysed using advanced signal processing techniques at Northumbria. Work has started in using these techniques to develop new systems and algorithms for fast underwater acoustic communications.
People: Professor S Danaher, Dr K Busawon