Data Integrity and Combinatorics Research Unit

Head of Unit: Professor Derek H. Smith BSc PhD DSc CMath FIMA

The work of this research unit is primarily concerned with the theory and applications of error-correcting codes and with applications of combinatorial mathematics, especially in radio system planning.

The work on codes includes:

• Synchronization of variable length codes;
• Constructions of constant weight codes;
• Codes for use in maximizing the number of users and minimizing interference in code- division multiple-access radio systems and mobile telephone systems.

A particular strength in recent years has been in applications of graph theory and meta-heuristic algorithms to frequency assignment in mobile telephone systems and other radio systems. Good frequency assignments minimize interference and use valuable radio spectrum efficiently. The Unit has been particularly successful in demonstrating the
effectiveness of the methods it has developed on sets of “benchmark problems”.

The work has been supported by BAE SYSTEMS, QinetiQ, EPSRC, ComOpt AB and the former Radiocommunications Agency (now Ofcom).