: pp. 17-20
Lviv Polytechnic National University, Ukraine
Lviv Polytechnic National University, Ukraine
Lviv Polytechnic National University, Ukraine

Digital  frequency  synthesizers  are  widely  used  in  various  fields  of  technology.  Their  main  advantages, compared  to  analog  devices,  are  the  accuracy  of  output  signal,  resistance  to  external  factors,  reliability  and  high  performance. Their structures include the digital storage device (accumulative adder) and a comparison scheme. Basing the latest the two-level digital frequency synthesizers are developed. They are the subset of digital frequency synthesizers, in which the output signals are two-levelled. The papers show the improved structures of digital frequency synthesizers with the extended functional capabilities, in which the possibility of the step of the output frequency alteration is implemented.

Poisson pulse sequence generators are used mainly to simulate various natural and technical processes that are subjects of the Poisson distribution  law. They  can be  implemented basing on different  structures. For  instance,  the basis of one of  them  is provided by a pseudorandom number generator and a comparison scheme.

The similarity of the two-level digital frequency synthesizers and Poisson pulse sequence generators constructing principles allow  conjugate  them  in one structure. Here,  the extended possibilities  for managing  the output  signal  frequency  are  combined with  its  formation  in  accordance with  the  Poisson  distribution  law.  Such  a  frequency  synthesizer  can  be  applied  to  simulate different  processes.  In  particular,  one  application  consists  in  simulation  of  the  output  signals  of  the  dosimetric  detectors.  It  is caused  by  active  search  of  various  types  of  extremist  and  terrorist  organizations  around  the world  and  puts  on  the  agenda  an increased  control  over  the  movement  of  radioactive  materials  both  internally  and  through  borders  of  countries,  including strengthening  control  over  their  movement  through  sea  ports  and  airports.  It  produces  the  new  requirements  aiming  the enhancement of the speed, accuracy, and reliability of dosimetric measurements.

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[12] Yu. Kostiv, V. Maksymovych, O. Harasymchuk, M.  Mandrona  “Methodology  for  Research  of  Poisson  Pulse Sequence  Generators  Using  Pearsons’s  Chi-Squared  Test”, Sustainable Development.  International  Journal,  vol.  9,  June 2013, Varna, pp. 67–72.

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