From 244d2291eb2655cbd1b6e9caf99c9c00ab75a4d8 Mon Sep 17 00:00:00 2001 From: Joe Taylor Date: Wed, 30 Aug 2017 17:06:49 +0000 Subject: [PATCH] Updates to User Guide. git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@8049 ab8295b8-cf94-4d9e-aec4-7959e3be5d79 --- doc/user_guide/en/decoder_notes.adoc | 37 +++++++++++++++++----------- 1 file changed, 23 insertions(+), 14 deletions(-) diff --git a/doc/user_guide/en/decoder_notes.adoc b/doc/user_guide/en/decoder_notes.adoc index d4f966a69..db10b3312 100644 --- a/doc/user_guide/en/decoder_notes.adoc +++ b/doc/user_guide/en/decoder_notes.adoc @@ -9,33 +9,25 @@ When an operator decides to answer a CQ, he already knows his own callsign and that of his potential QSO partner. He therefore knows what to expect for at least 56 of the 72 message bits in a standard-format response to his call. The _WSJT-X_ decoders for QRA64 -and FT8 can use these AP bits to decode messages containing them with -higher sensitivity than otherwise possible. +and FT8 can use these and similar AP bits to decode messages +containing them with higher sensitivity than otherwise possible. We have implemented AP decoding in slightly different ways in QRA64 and FT8. To provide some explicit examples for users, we provide here a brief description of the FT8 behavior. -The FT8 decoder always tries first to decode a signal without using -any AP information. If this attempt fails, and if *Enable AP* is -checked on the *Decode* menu, a second attempt hypothesizes that the -message contains callsigns MyCall and DxCall. If the QSO has -progressed to the point where signal reports have been exchanged, a -third attempt hypothesizes that the message contains the known -callsigns followed by RRR, RR73, or 73. - AP decoding attempts effectively set the AP bits to the hypothesized -values, as if they had been received perfectly. The decoder then +values, as if they had been received correctly. The decoder then proceeds to determine whether the remaining message and parity bits are consistent with the hypothesized AP bits. If a codeword is found that the decoder judges to have high (but not overwhelmingly high) probability of being correct, a ? character is appended when the -decoded message is displayed. Decodes thus marked are not sent to -{pskreporter} to avoid occasional misleading spots of false decodes. +decoded message is displayed. To avoid misleading spots of occasional +false decodes, messages so marked are not forwarded to {pskreporter}. Successful AP decodes are always labeled with an end-of-line indicator of the form aP, where P is one of the single-digit AP decoding types -listed in Table 1. For example, an a2 designator says that the +listed in Table 1. For example, an `a2` designator says that the successful decode used MyCall as hypothetically known information. [[AP_INFO_TABLE]] @@ -51,6 +43,23 @@ successful decode used MyCall as hypothetically known information. |6 | MyCall DxCall RR73 |=============================================== +Table 2 lists the six possible QSO states that are tracked by the +WSJT-X auto-sequencer, along with the type of AP decoding that would +be attempted in each state. + +[[AP decoding types for each QSO state]] +[width="35%",cols="h10,