Abstract：
:Increasing output resolution is assumed to improve noise characteristics of a CCD digitizer. In this work, however, we have found that as the quantization step becomes lower than the analog noise (present in the signal before its conversion to digital) the noise reduction becomes significantly lower than expected. That is the case for values of sigma(an)/delta larger than 0.6, where sigma(an) is the standard deviation of the analog noise and delta is the quantization step. The procedure is applied to a commercially available CCD digitizer, and noise reduction by means of signal resolution increase is compared to that obtained by low pass filtering.
journal_name
Med Physjournal_title
Medical physicsauthors
González A,Martínez JA,Tobarra Bdoi
10.1118/1.1644672subject
Has Abstractpub_date
2004-03-01 00:00:00pages
525-7issue
3eissn
0094-2405issn
2473-4209journal_volume
31pub_type
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