Commit Graph

52 Commits

Author SHA1 Message Date
Joe Taylor b2a56fec8b Fis a few more compiler warnings. 2021-04-22 14:08:53 -04:00
Bill Somerville 22f1ba6a6d
Merge branch 'support-2.3.1' into release-2.4.0 2021-03-03 23:58:39 +00:00
Steven Franke b194cc1a14 FST4: Do not bail out of blanker loop after 1st decode. 2021-02-18 14:26:56 -06:00
Steven Franke b9d33bc998 Address compiler warnings in fst4/w code. 2021-01-07 10:05:53 -06:00
Steven Franke 0013b15120
Remove some debug code. 2021-01-04 15:00:05 +00:00
Steven Franke 46222c61ed
Add rudimentary sanity checks to the values parsed from FST4W_ALSO_FST4. 2021-01-04 15:00:05 +00:00
Steven Franke 41f587c240
Fix a conflict between noise baseline percentile level and noise blanker percentage. Both were using the npct variable. Add an option for an FST4 pass when in FST4W mode. 2021-01-04 15:00:05 +00:00
Steven Franke 0fef0cc6e6
Minor formatting change in fst4_decodes.dat. 2021-01-04 15:00:04 +00:00
Steven Franke a38b48d13d
Minor format change for nutc in fst4_decodes.dat. 2021-01-04 15:00:04 +00:00
Steven Franke 4081be94e1
Avoid a possible of bounds error. Compute some more decode diagnostic data. 2021-01-04 15:00:03 +00:00
Steven Franke 8079d35561
Append decoder data to file fst4_decodes.dat instead of overwriting. 2021-01-04 15:00:02 +00:00
Steven Franke 89cbd177df
If file decdata is present in the data directory, then write detailed decoder data to file fst4_decodes.dat in the same directory. 2021-01-04 15:00:02 +00:00
Steven Franke 812bd29e54
FST4W: Use K=66 for first OSD decode attempt and for updating fst4w_calls.txt. Use K=50 for 2nd attempt. 2021-01-04 15:00:02 +00:00
Steven Franke fc3e24f696
More work on K=50 decoding. 2021-01-04 15:00:01 +00:00
Steven Franke 65ff3ce05e
Remove some debug prints. 2021-01-04 15:00:01 +00:00
Steven Franke 11b7aa9429
Implements decoding of FST4W messages as (240,50) crc-less codewords.
By cascading the full 24-bit crc generator matrix with the (240,74) LDPC code generator, create a (240,50) generator that is used to decode with approximately 1 dB better sensitivity than the (240,64) with 14-bit CRC approach that is normally used. This approach treats the CRC bits as additional parity bits and provides no means for identifying incorrect codewords. All codewords on the list generated by the OSD algorithm have CRCs that match the CRC of the message payload. Codewords are validated by unpacking the message and comparing the unpacked message with the list of stored callsign/grid pairs stored in the fst4w_calls.txt file.
2021-01-04 14:59:56 +00:00
Joe Taylor 9200c3e27a Add NB = -3% option to cycle through NB=0, 1, 2, 3, ... 20%. 2020-09-30 13:32:03 -04:00
Joe Taylor 0ab3e5116f Fix several flaws in the loop-over-NB logic in the FST4 decoder. 2020-09-19 10:08:42 -04:00
Joe Taylor 2af01ebaa1 Fix a flaw in the loop-over NB logic. There are more flaws! 2020-09-18 15:52:33 -04:00
Joe Taylor f0ed93cdd0 In the NB-loop, don't cycle around a decode attempt for the npct=0 pass. 2020-09-18 11:45:28 -04:00
Joe Taylor 52bdd57e57 Implement NB=-1%, NB=-2%. Fix a startup problem with WideGraps's fMax value. 2020-09-18 11:30:23 -04:00
Joe Taylor 375a869a51 Revert "Revert "Very basic code (including some diagnostics) for "try all NB settings". Will remove it again.""
This reverts commit 033cc65d08.
2020-09-18 09:01:51 -04:00
Joe Taylor 033cc65d08 Revert "Very basic code (including some diagnostics) for "try all NB settings". Will remove it again."
This reverts commit bcf7f36b9c.
2020-09-17 19:30:07 -04:00
Joe Taylor bcf7f36b9c Very basic code (including some diagnostics) for "try all NB settings". Will remove it again. 2020-09-17 19:28:55 -04:00
Steven Franke 7d58df4cc1 In FST4 mode with Single Decode not checked, move candidates within 20 Hz of nfqso to the top of the list. 2020-09-17 14:22:38 -05:00
Joe Taylor 21dc6a5c59 Connect the FLow and FHigh limits for FST4 decoding. 2020-09-16 17:23:59 -04:00
Steven Franke 221ede2903 Remove some unused variables. 2020-09-14 13:07:07 -05:00
Steven Franke ca0804450b Remove some redundant code. 2020-09-14 09:07:45 -05:00
Steven Franke 98d52e35ac Speed up FST4 decoding. 2020-09-14 09:00:30 -05:00
Steven Franke 71fdcd1119 Silence a compiler warning. 2020-09-10 16:11:07 -05:00
Steven Franke 2dcde590df Use widegraph limits for noise baseline fit. Limit signal search to within the widegraph limits. 2020-09-10 14:58:10 -05:00
Joe Taylor 47fcddcb50 Send nfa, nfb to fst4_decode(). 2020-09-10 14:59:52 -04:00
Joe Taylor 01a1688b32 FST4 and FST4W decoder: get freq range from nfqso and ntol; remove BCD submodes, i.e. hmod=2, 4, 8. 2020-09-05 13:14:40 -04:00
K9AN f066936043
Remove an unused variable from fst4_decode 2020-08-29 19:55:23 +01:00
Steven Franke 5ca81a6507
Use 3rd order polynomial fit to estimate the noise baseline. The
polynomial fit is done over 400 Hz bandwidth for T/R periods longer
than 15s, and over approx. 600 Hz (10 times the signal bandwidth) for
T/R period of 15s.
2020-08-29 19:55:23 +01:00
Steven Franke d82b9f5b0e
Speed up decoder by eliminating some complex multiples in sequence detection loop. Add timer calls for doppler spread calculation and sequence detection loop. 2020-08-29 19:55:22 +01:00
Steven Franke ecaca6af9f
Fix argument list in call to fet_fst4_bitmetrics.f90 2020-08-29 19:55:22 +01:00
Steven Franke e02850ae5a
Streamline fst4_decode. Add timer for downsampling. 2020-08-29 19:55:22 +01:00
Steven Franke 782c779392
Reconfigure to optimize decoder for MF/LF (high coherence) channels. 2020-08-29 19:55:21 +01:00
Steven Franke 7cb5511ed0
Simplify some code in fst4_decode.f90 - no functional change. 2020-08-29 19:55:21 +01:00
Steven Franke bf06193c10
Add timer call for bit metric calculation. Improve some comments. Make fort.21 ntype parameter more informative. 2020-08-29 19:54:38 +01:00
Steven Franke 6838a6b484
Remove some unneeded code. 2020-08-29 19:50:32 +01:00
Steven Franke 8b7db6556c
Changes to the llrs that are used as the basis for AP decoding. 2020-08-29 19:50:17 +01:00
Steven Franke b191e0c5ef
Fix SNR calculation for B,C,D submodes. 2020-08-29 19:49:59 +01:00
Steven Franke 9d2bde7180
Fix SNR calculation for B,C,D submodes. 2020-08-29 19:49:46 +01:00
Joe Taylor 902c0b7a59 Protect against bounds error in dopspread.f90. Remove the temporary ssavg code. 2020-07-29 09:48:19 -04:00
Joe Taylor 884854223c Add computation of an average spectrum of unmodulated FST4 signals after decoding. 2020-07-27 14:02:33 -04:00
Joe Taylor 4455861773 Merge branch 'feat-fst280' of bitbucket.org:k1jt/wsjtx into feat-fst280 2020-07-27 08:27:46 -04:00
Joe Taylor 79be2a7790 Reformat the fort.21 output. 2020-07-27 08:27:16 -04:00
Steven Franke 3de14a5436 Tweak SNR calibration. 2020-07-26 19:31:20 -05:00