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Re: [wsjt-devel] FT8 notes
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From: Steven F. <s.j...@ic...> - 2017-06-30 15:00:28
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Joe, OK. osd can only be successful if it is given candidates. I’m noticing now that the current sync threshold is high enough where bp probably doesn’t fail all that often. In any case, more candidates fed to osd would only increase the fraction of time spent in that routine. It doesn’t seem likely that osd is going to be able to pull it’s weight. I’m fine if you want to just remove the call to osd all together, at least for now. Steve > On Jun 30, 2017, at 9:45 AM, Joe Taylor <jo...@pr...> wrote: > > Hi Steve, > > Yes, 40 iterations for bp. > > With norder=2 hardwired for everything I still get 574 good decodes. So at least in jt9.exe, with no attempt to move nfqso around, using norder=3 produces no more decodes. > > Here are the timer results with norder=2: > > Name Time Frac dTime dFrac Calls > ---------------------------------------------------------- > jt9 33.832 1.00 0.691 0.02 1 > read_wav 0.164 0.00 0.164 0.00 27404 > decft8 32.977 0.97 0.055 0.00 527 > sync8 4.148 0.12 4.148 0.12 527 > ft8b 28.773 0.85 0.090 0.00 2821 > bpd174 1.641 0.05 1.641 0.05 2821 > osd174 27.043 0.80 27.043 0.80 2210 > ---------------------------------------------------------- > 33.832 1.00 > > -- Joe > > On 6/30/2017 10:34 AM, Steven Franke wrote: >> Joe, >> Were these results obtained with 40 iterations for bp and norder = 3 for signals at or within 10 Hz of nfqso? If so, it might be interesting to see how the numbers would change if you dropped back to norder=2 for all signals. >> Steve >>> On Jun 30, 2017, at 9:25 AM, Joe Taylor <jo...@pr...> wrote: >>> >>> Hi all, >>> >>> Thanks for a busy ~20 hours of many people testing FT8. I now have accumulated a directory with 527 *.wav files, each of which has at least one visible FT8 signal. The files were recorded at K1JT at either 14.079 or 50.313 MHz. >>> >>> Running the r7753 stand-alone slow-mode decoder jt9[.exe] on this collection of files produces 574 valid decodes and 0 false decodes with total execution time 39.8 s. The average time to process a 15 s Rx sequence on this machine (Core i7-6700 @ 3.4 GHz) is thus 39.8/527 = 0.076 s. Not bad! >>> >>> Here's the detailed execution-time breakdown from timer.out: >>> >>> Name Time Frac dTime dFrac Calls >>> ---------------------------------------------------------- >>> jt9 39.828 1.00 0.734 0.02 1 >>> read_wav 0.121 0.00 0.121 0.00 27404 >>> decft8 38.973 0.98 0.133 0.00 527 >>> sync8 4.191 0.11 4.191 0.11 527 >>> ft8b 34.648 0.87 0.051 0.00 2821 >>> bpd174 1.480 0.04 1.480 0.04 2821 >>> osd174 33.117 0.83 33.117 0.83 2210 >>> ---------------------------------------------------------- >>> 39.828 1.00 >>> >>> Note that 83% of the execution time is spent in routine osd174, 11% in sync8, and 4% in bpd174 (a contraction for subroutine name bpdecode174). >>> >>> It turns out that only 14 of the 574 decodes were produced by osd174, the "ordered statistics" decoder. The rest came from bpd174. With osd174 deactivated, timer.out looks like this: >>> >>> Name Time Frac dTime dFrac Calls >>> ---------------------------------------------------------- >>> jt9 6.641 1.00 0.891 0.13 1 >>> read_wav 0.168 0.03 0.168 0.03 27404 >>> decft8 5.582 0.84 0.094 0.01 527 >>> sync8 3.887 0.59 3.887 0.59 527 >>> ft8b 1.602 0.24 0.109 0.02 2821 >>> bpd174 1.492 0.22 1.492 0.22 2821 >>> osd174 0.000 0.00 0.000 0.00 2210 >>> ---------------------------------------------------------- >>> 6.641 1.00 >>> >>> Now the average execution time for a 15 s Rx sequence is just 13 ms! >>> >>> We need to keep decoding time very short -- say, well under 1 s -- so that auto-sequencing, if not the human operator, can select proper responses to received messages. Fortunately, we already have good baseline performance -- and we have a number of "knobs" to play with. >>> >>> -- Joe, K1JT >>> >>> ------------------------------------------------------------------------------ >>> Check out the vibrant tech community on one of the world's most >>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot >>> _______________________________________________ >>> wsjt-devel mailing list >>> wsj...@li... >>> https://lists.sourceforge.net/lists/listinfo/wsjt-devel >> ------------------------------------------------------------------------------ >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, Slashdot.org! http://sdm.link/slashdot >> _______________________________________________ >> wsjt-devel mailing list >> wsj...@li... >> https://lists.sourceforge.net/lists/listinfo/wsjt-devel > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > wsjt-devel mailing list > wsj...@li... > https://lists.sourceforge.net/lists/listinfo/wsjt-devel |
