The publications presented arc divided into those constituting the core of the
submission and those which are considered to be of secondary material. In Section 2 a
commentary on the core research publications identifies two closely related themes. The first
theme, presented in Section 2.1, discusses my published articles on delta modulation and digital
encoding of speech and picture signals. While conducting research into digital encoding I
became involved with techniques for combating the effect of transmission errors in digitally
encoded speech and picture signals, and my publications on this subject are described in Section
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Science at Loughborough University. This Thesis consists of copies of separate publications. It has been redacted for reasons relating to the law of copyright. For more information please contact the author.