i++ School Newsletter

Week commencing 28 June 2010

Previous Newsletters

New Book Published by CSEE Academic

Dr Ramaswamy Palaniappan has written a new book titled Biological Signal Analysis.

Analysing biological signals such as electrocardiogram and electroencephalogram has become very important with modern healthcare striving to provide cost effective point-of care diagnosis and personalised treatment. Furthermore, fast computing power in recent years has made much of the more complex analysis methodologies possible. This free textbook will provide the reader with an understanding of biological signals and digital signal analysis techniques such as conditioning, filtering, feature extraction, classification and statistical validation for solving practical biological signal analysis problems using MATLAB. The text will be useful to students in any field with interest in biological signal analysis. As the contents also cover signal processing and intelligent classification methodologies, students studying digital signal processing and machine learning courses will also find it useful. It will also be appropriate for the researchers in both industry and academia, especially those from non-technical background who would be interested in analysing biological signals - the text does not assume any prior signal processing knowledge and MATLAB is used throughout the text to minimise programming time and difficulty and concentrate on the ‘analysis’, which is the focus of this book. The book can be downloaded for free at the Book Boon website.

Preprint Published

Nicolas Le Bihan and Stephen J. Sangwine, The hyperanalytic signal, e-print arXiv:1006.4751, 24 June 2010, available here.

Abstract - The concept of the analytic signal is extended from the case of a real signal with a complex analytic signal to a complex signal with a hypercomplex analytic signal (which we call a hyperanalytic signal) The hyperanalytic signal may be interpreted as an ordered pair of complex signals or as a quaternion signal.

The hyperanalytic signal contains a complex orthogonal signal and we show how to obtain this by three methods: a pair of classical Hilbert transforms; a complex Fourier transform; and a quaternion Fourier transform. It is shown how to derive from the hyperanalytic signal a complex envelope and phase using a polar quaternion representation previously introduced by the authors. The complex modulation of a real sinusoidal carrier is shown to generalize the modulation properties of the classical analytic signal. The paper extends the ideas of properness to deterministic complex signals using the hyperanalytic signal. A signal example is presented, with its orthogonal signal, and its complex envelope and phase.