Commit Graph

51 Commits

Author SHA1 Message Date
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
Bill Somerville
a7223a5efa
A few more cosmetic 240 -> 4 changes 2020-07-23 19:13:05 +01:00