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Charles G. Sodini and Martin Choquette. Bieniosek, Matthew (Matthew F.) Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science 2011-04-25T14:15:29Z 2011-04-25T14:15:29Z 2010 2010 http://hdl.handle.net/1721.1/62309 710219017 Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Cataloged from student-submitted PDF version of thesis. Includes bibliographical references (p. 81-82). The arrival of photons at a given location is a Poisson process with an associated shot noise which rises with the square root of the number of photons received. An analog-to-digital converter (ADC) with a square root transfer function can quantize photonic signals with LSB size kept constant with respect to the photon shot noise. In imaging applications, this can greatly reduce the number of bits needed to characterize a signal compared to a linear ADC without detrimental effects to image quality. Such a device, based on the Analogic MuSIC chip, was designed and tested for the needs of a medical computed tomography (CT) device. The experimental setup increases the MuSIC sampling frequency from 3kHz to 7kHz, while reducing the amount of data necessary for reconstruction. A constant quantization noise to photon shot noise ratio acceptable for CT is maintained by sizing each LSB to be one half the rms noise level. Results show an INL of 2.5 LSB, which is reduced to 0.27 LSB after a correction scheme. by Matthew Bieniosek. M.Eng. 82 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Electrical Engineering and Computer Science. A square root analog to digital converter to optimally convert photonic signals for computed tomography Square root ADC converter to optimally convert photonic signals for CT Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="c97a448d-9ba7-4b91-9972-15af6808825a"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>A square root analog to digital converter to optimally convert photonic signals for computed tomography</Title> <Subtitle>Square root ADC converter to optimally convert photonic signals for CT</Subtitle> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2010</PublicationDate> <Authors> <Author> <DisplayName>Bieniosek, Matthew (Matthew F.)</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Electrical Engineering and Computer Science.</Keyword> <Abstract>The arrival of photons at a given location is a Poisson process with an associated shot noise which rises with the square root of the number of photons received. An analog-to-digital converter (ADC) with a square root transfer function can quantize photonic signals with LSB size kept constant with respect to the photon shot noise. In imaging applications, this can greatly reduce the number of bits needed to characterize a signal compared to a linear ADC without detrimental effects to image quality. Such a device, based on the Analogic MuSIC chip, was designed and tested for the needs of a medical computed tomography (CT) device. The experimental setup increases the MuSIC sampling frequency from 3kHz to 7kHz, while reducing the amount of data necessary for reconstruction. A constant quantization noise to photon shot noise ratio acceptable for CT is maintained by sizing each LSB to be one half the rms noise level. Results show an INL of 2.5 LSB, which is reduced to 0.27 LSB after a correction scheme.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>