TY - GEN
T1 - Design of a 2-Bit Sigma-Delta Modulator for Scintillation Waveform Capture
AU - Ruiz-Gonzalez, Maria
AU - Furenlid, Lars R.
N1 - Funding Information:
Manuscript received November 9, 2017. This work was supported in part by NIH/NIBIB under grants P41-EB002035 and R01-EB022521. The work of M. Ruiz-Gonzalez was supported in part by the Mexican National Council of Science and Technology (CONACYT).
Publisher Copyright:
© 2017 IEEE.
PY - 2018/11/12
Y1 - 2018/11/12
N2 - Sigma-delta modulation is a common technique used in analog-to-digital conversion. It has been shown that it can be implemented in a field-programmable gate array (FPGA) using minimal external analog components. Zhao et al. demonstrated that energy of scintillation pulses can be computed by adding up all the elements on the output from a conventional 1-bit sigmadelta modulator. However, for parameters selected for a suitable resolution and dynamic range, the system passes through a period of saturation. During saturation, information about the shape of the pulse is lost even though the integrated energy remains preserved. We present the design of a 2-bit version of the sigmadelta modulator that makes use of a nonlinear adaptive digital-toanalog converter (DAC) that keeps the system unsaturated. Each output bit is scaled by one of the four possible values the DAC can take, resulting in a 2-bit modulation. We have demonstrated that the 2-bit modulation retains information about the pulse shape.
AB - Sigma-delta modulation is a common technique used in analog-to-digital conversion. It has been shown that it can be implemented in a field-programmable gate array (FPGA) using minimal external analog components. Zhao et al. demonstrated that energy of scintillation pulses can be computed by adding up all the elements on the output from a conventional 1-bit sigmadelta modulator. However, for parameters selected for a suitable resolution and dynamic range, the system passes through a period of saturation. During saturation, information about the shape of the pulse is lost even though the integrated energy remains preserved. We present the design of a 2-bit version of the sigmadelta modulator that makes use of a nonlinear adaptive digital-toanalog converter (DAC) that keeps the system unsaturated. Each output bit is scaled by one of the four possible values the DAC can take, resulting in a 2-bit modulation. We have demonstrated that the 2-bit modulation retains information about the pulse shape.
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U2 - 10.1109/NSSMIC.2017.8532727
DO - 10.1109/NSSMIC.2017.8532727
M3 - Conference contribution
AN - SCOPUS:85057400379
T3 - 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2017 - Conference Proceedings
BT - 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2017 - Conference Proceedings
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2017
Y2 - 21 October 2017 through 28 October 2017
ER -