Commit Graph

4 Commits

Author SHA1 Message Date
Steve Pinkham
7fcf035337 edac: correct Golay(24,12) words that are not at the start of the message (#2631)
Golay24.checkAndCorrect indexed the word from bit 0 (getInt(0, 22), xor(12, ...),
flip(index)) and took the parity over the whole message, so it was only right for a
message that is exactly one 24-bit word. P25 TDULC words 2-12 and the DMR voice
superframe words at 24 and 48 were "corrected" in the wrong bits. Decode any other
word in a 24-bit copy and write it back.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-11-13 01:29:50 -05:00
Denny Sheirer
9a6dc2b0a0 #2524 P25P2 Decoder enhancements (#2525)
* Adopts same architecture and symbol processor as P1 C4FM/LSM, DMR and NXDN.
* Soft symbol sync detection, processing and erro correction.
* Scalar and vector soft sync detection and calibration
* Improved time slot detection/prediction and ISCH processing.
* Fixes bug in parsing sequential mac structures in SACCH
* Vector calibration(s) cleanup across multiple calibrations
* Error correction bug in ISCH
* Renames differential demod shared with P1 LSM decoder.

Co-authored-by: denny <dennis.sheirer@gmail.com>
2026-10-29 07:32:17 -04:00
Denny Sheirer
6b9cd2d317 #2518 P25P1 LSM Decoder enhancements. (#2523)
* Uses same shared architecture and symbol processor pattern as other C4FM decoders.
* Adds soft symbol processing and sync detection.
* Removes RRC filter and replaces with improved channel filter.
* Viterbi soft symbol decoding with demodulator reliability weighting
* Improved sync reacquisition in low SNR
* Improved handling for phase wrapping and interpolation
* NAC Tracker updated to track by NAC count
* Native buffers returning partial buffers
* Message processor uses only valid LDU1 words
* Reduced phantom TDU messages
* Tuner/Channe frequency error corrections don't reset the symbol trackers and fix possible divide by zero error
* LSM timing error detector now updates per symbol block size instead of sample buffer size - faster convergence
* New unit tests
* Resolves several issues, including a lagging sync detect offset issue in the recently updated P25P1 C4FM decoder.
* Consolidate filter designers for each protocol back into the FilterFactory class.
* DMR, P25 Phase 1 C4FM and LSM, and P25 Phase 2 decoders design the baseband filter once and share the taps across the I and Q filters.

Co-authored-by: denny <dennis.sheirer@gmail.com>
2026-10-29 04:17:47 -04:00
Denny Sheirer
8718d04ef5 #2162 APCO25 NID BCH decoder implementation. (#2163)
Co-authored-by: Dennis Sheirer <dsheirer@github.com>
2025-02-27 09:09:46 -05:00