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Title: Automatic pole-zero/zero-pole digital compensator for high-resolution spectroscopy: Design and experiments

Abstract

In a high-resolution spectroscopy system the relatively long exponential decay due to the charge preamplifier is customarily canceled in an analogue fashion by means of a PZ (Pole-Zero) stage. The accurateness of such a compensation has a big impact on the energy resolution because it strongly affects the baseline-stability problems. The authors have automatically and on-line performed such a compensation in a digital way, while maintaining a spectroscopy performance and keeping at minimum both the ADC sampling frequency (thus power consumption) and its resolution (thus cost). This is done through an IIR filter, implemented within a FPGA by a DSP. The so-compensated waveform has, in excellent approximation, an all-pole shape. Starting from such a signal, the minimum-noise filters for energy and/or time measurements are then promptly synthesized and implemented for real time operation through the same DSP.

Authors:
; ;  [1]
  1. Politecnico di Milano (Italy). Dipt. di Elettronica e Informazione
Publication Date:
OSTI Identifier:
684538
Report Number(s):
CONF-981110-
Journal ID: IETNAE; ISSN 0018-9499; TRN: 99:010065
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Transactions on Nuclear Science; Journal Volume: 46; Journal Issue: 4Pt1; Conference: 1998 IEEE nuclear science symposium and medical imaging conference, Toronto (Canada), 10-12 Nov 1998; Other Information: PBD: Aug 1999
Country of Publication:
United States
Language:
English
Subject:
44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; SPECTROMETERS; ENERGY RESOLUTION; ANALOG-TO-DIGITAL CONVERTERS; LOGIC CIRCUITS; PULSE SHAPERS; DESIGN

Citation Formats

Geraci, A., Pullia, A., and Ripamonti, G.. Automatic pole-zero/zero-pole digital compensator for high-resolution spectroscopy: Design and experiments. United States: N. p., 1999. Web. doi:10.1109/23.790684.
Geraci, A., Pullia, A., & Ripamonti, G.. Automatic pole-zero/zero-pole digital compensator for high-resolution spectroscopy: Design and experiments. United States. doi:10.1109/23.790684.
Geraci, A., Pullia, A., and Ripamonti, G.. 1999. "Automatic pole-zero/zero-pole digital compensator for high-resolution spectroscopy: Design and experiments". United States. doi:10.1109/23.790684.
@article{osti_684538,
title = {Automatic pole-zero/zero-pole digital compensator for high-resolution spectroscopy: Design and experiments},
author = {Geraci, A. and Pullia, A. and Ripamonti, G.},
abstractNote = {In a high-resolution spectroscopy system the relatively long exponential decay due to the charge preamplifier is customarily canceled in an analogue fashion by means of a PZ (Pole-Zero) stage. The accurateness of such a compensation has a big impact on the energy resolution because it strongly affects the baseline-stability problems. The authors have automatically and on-line performed such a compensation in a digital way, while maintaining a spectroscopy performance and keeping at minimum both the ADC sampling frequency (thus power consumption) and its resolution (thus cost). This is done through an IIR filter, implemented within a FPGA by a DSP. The so-compensated waveform has, in excellent approximation, an all-pole shape. Starting from such a signal, the minimum-noise filters for energy and/or time measurements are then promptly synthesized and implemented for real time operation through the same DSP.},
doi = {10.1109/23.790684},
journal = {IEEE Transactions on Nuclear Science},
number = 4Pt1,
volume = 46,
place = {United States},
year = 1999,
month = 8
}
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