воскресенье, 16 августа 2009 г.

SA update to version

SA update to version.

In the previous version, the filter LPF operation in WF module, at various frequency measurements was recognised as unsatisfactory.

The difficulties are linked with that usage of double filtering circuits, which is strongly displaces the frequency of filter's cut, and it causes some difficulties with choosing and setup of filter's parametres.

In the most of cases, it is necessary to take frequency of the filter's cut considerably above the measured frequency of manipulation, and as result it remains vague: how much it is possible to trust to the histogram. In general, these problems are standard, because it is depends on signal's quality of how much strong it is necessary to process initial signal by the filter, after the phase/frequency detector, for reception of reliable histogram of the frequencies allocation.

But, in the previous version, this problem was expressed too obvious. We have removed the double circuit.

As a result we have:

  • the filtering is became much accurate
  • the frequency of filtrum's cut corresponds to the value, which is specified manually or selected from the list,
  • results of filtering allow to reach an excellent quality of the histograms even on the signals with the very strong and high level of noise.

In hard cases there several cycles of filtering can be demanded, however as practice shows: two cycles are quite enough. Ofcourse, it demands some skills and experience, but current implementation of LPF, in any case gives considerably best results, than former one.

This update also contains a lot of hardly noticeable, but the important improvements.

Good Luck!