From 6a7a9ce6bf1642db4b191a9fdb2c56d5fb4725c8 Mon Sep 17 00:00:00 2001 From: Steven Franke Date: Thu, 1 Sep 2016 16:08:23 +0000 Subject: [PATCH] Fix sigma ramp-up for short messages in msk40. Should decrease false decodes. git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7050 ab8295b8-cf94-4d9e-aec4-7959e3be5d79 --- lib/detectmsk40.f90 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/detectmsk40.f90 b/lib/detectmsk40.f90 index 3920c3a0a..9c0d25680 100644 --- a/lib/detectmsk40.f90 +++ b/lib/detectmsk40.f90 @@ -378,7 +378,7 @@ subroutine detectmsk40(cbig,n,pchk_file,mycall,hiscall,lines,nmessages, & softbits=softbits/ssig sigma=0.75 - if(xsnr.lt.1.5) sigma=1.1 - 0.0875*(xsnr+4.0) + if(xsnr.lt.0.0) sigma=0.75-0.0875*xsnr lratio(1:32)=exp(2.0*softbits(9:40)/(sigma*sigma)) ! Use this for Radford Neal's routines llr(1:32)=2.0*softbits(9:40)/(sigma*sigma) ! Use log likelihood for bpdecode40