Nuclear Techniques ›› 2015, Vol. 38 ›› Issue (5): 50401-050401.doi: 10.11889/j.0253-3219.2015.hjs.38.050401


Method of digital Dither adding for digital multi-channel pulse amplitude analyzer

CHEN Xiaomeng ZHANG Yuzhong AI Xianyun LIANG Weiping XIAO Wuyun   

  1. (State Key Laboratory of Nuclear Biological Chemical Protection for Civilian, Research Institute of Chemical Defense, Beijing 102205, China)
  • Received:2014-12-25 Revised:2015-02-13 Online:2015-05-10 Published:2015-05-08

Abstract: Background: The key technology of digital multi-channel pulse amplitude analyzer (DMCA) has been surmounted in China, however, with the increasing of the translation gain increases of DMCA, one of the difficulties is how to make the nonlinear performance index of the system reach the standard. Technology of Dither has been used to realize “Bit Gain” in overseas research while it is still a deficiency in DMCA study in China. Purpose: This study aims to study the application of Dither technology in DMCA and discuss relevant digital Dither technology for DMCA. Method: Based on DMCA architecture characteristics, Dither signal is produced and removed in field programmable gate array (FPGA) by linear feedback shift register (LFSR), and is added to DMCA by the circuit of base line. Energy resolution and differential nonlinearity (DNL) of DMCA system has been measured to study the effect of Dither on DMCA. The mechanism of how the Dither affects DMCA has been analyzed. Results: Experimental tests showed that DNL of DMCA is improved by adding Dither while keep the same the energy resolution, verifying the applicability of this method. Conclusion: The technology method of digital Dither adding for DMCA is of practical significance to the further research to improve the precision of DMCA.

Key words: Digital Dither technology, DMCA, FPGA, LFSR, DNL