Abstract:
:Noise in the composite magnitude signal from multiple-coil systems is usually assumed to follow a noncentral χ distribution when sum of squares is used to combine images sensed at different coils. However, this is true only if the variance of noise is the same for all coils, and no correlation exists between them. We show how correlations may be obviated from this model if effective values are considered. This implies a reduced effective number of coils and an increased effective variance of noise. In addition, the effective variance of noise becomes signal-dependent.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Aja-Fernández S,Tristán-Vega Adoi
10.1002/mrm.23020subject
Has Abstractpub_date
2012-02-01 00:00:00pages
580-5issue
2eissn
0740-3194issn
1522-2594journal_volume
67pub_type
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