Dr Alan Stocker
Alan Stocker
Associate Professor in Radio Systems
T: +44 (0)116 252 2520
E: sto@le.ac.uk
ORCID: http://orcid.org/0000-0002-4948-6932
Location: Room 11, R Block, Engineering
Personal details
BSc, PhD, MIET, SFHEA
Teaching
2018/19
EG2202 (Semester 2). I will cover the propagation of plane waves (in dielectric and lossy materials) and propagation in waveguides.
EG4017 (Semester 1). I will introduce a brief history of engineering, the role of innovation, and intellectual property rights. I will also cover leadership and ethics.
EG4212/7021 (Semester 1). I will discuss the design and operating parameters for a range of radio systems (e.g. radars, navigation systems, etc.).
Publications
My publications, including links to full-text versions of some papers, can be found HERE.Research
My current research interests lie in three different fields of transportation and in wireless sensor networks
Communication with commercial aircraft in the polar cap
Commercial aircraft are required to remain in contact with air-traffic control throughout their flight. In areas where there is ground infrastructure, VHF radio is used for this purpose. However, this is limited to operating over line of sight and therefore where there is no ground infrastructure, the aircraft rely on long distance communications via HF. In order to achieve long distance propagation, the HF radio signals have to reflect from the ionosphere, which is a region of the atmosphere that is ionised by UV radiation from the sun and is also strongly affected by conditions on the sun ('space weather'). For aircraft operating on polar routes (e.g. between New York and Hong Kong), events on the sun (e.g. solar flares) can make communications difficult. Our research interest is in forecasting how well HF communications will behave over a period from about 6 hours before take-off until landing.
Vehicle-to-vehicle communication
Connected and autonomous vehicles (CAV) of which self-drving cars are the best known, will rely on a range of technologies both to sense their location and the location of other road users and to communicate. We have undertaken measurements of radio propagation and network performance at road T-junctions that differed in how built up they were. While the communication systems worked relatively well around the junction, we established the limitations in range and performance. We have also looked at the effect of scaling on network performance, i.e. as the number of connected vehicles increases the reliability of communications is likely to decrease with the amount of decrease depending on the routing protocol in use.
Communication with spacecraft during solar conjunction
From a perspective on the Earth, a superior solar conjunction is when a spacecraft (or planet) appears to go behind the sun. While spacecraft behind the sun cannot be communicated with directly, when they are within a few degrees of the sun, the ionised gasses (or plasma) in the solar corona strongly affect the radio signals used for communication. In this work we have quantified the effect of the solar corona on the radio signals and then, using a simulator developed as part of the project, investigating the potential of new technologies to improve the reliability or data rates of communications.
Wireless sensor networks
Wireless sensor networks (including those deployed as part of the Internet of Things) are only able to function properly if they can maintain reliable communications. Work currently being undertaken by several PhD students has concentrated on controlling congestion in event driven networks. We have a large (90 nodes) wireless sensor network testbed based on the Waspmote Xbee Pro platform that allows us to design and test clustering and routing protocols experimentally.