Elizabeth Mary Tunnicliffe1,2, Martin John
Graves1,3, Matthew D. Robson4
1Department of Medical
Physics & Clinical Engineering, Addenbrooke's Hospital, Cambridge, United
Kingdom; 2AVIC, Nuffield Department of Clinical Medicine,
University of Oxford, Oxford, United Kingdom; 3Department of
Radiology, University of Cambridge, Cambridge, United Kingdom; 4OCMR,
Department of Cardiovascular Medicine, University of Oxford, Oxford, United
Kingdom
The noise covariance matrix of a phased array coil provides information about both the noise level in individual channels and the correlations between channels. It can therefore be useful in quality assurance procedures as these characteristics are liable to change in the case of coil failure. This work presents examples of noise covariance matrices of functioning and failing arrays and suggests quantitative limits, beyond which remedial action may be required.