Channel Analyzer (NG) updates
Support exploration of PSK signals adding the following features:
- PLL with multi-phase locking able to lock to signals with 1 (CW), 2 (BPSK), 4 (QPSK), 8 or 16 equally spaced phase symbols. The NCO of the PLL is then mixed with the signal to achieve de-rotation.
- Trace projection mapping phase sectors to levels in the [-1..1] range for soft symbol display.
- Extension to FLL locking for FM signals (AFC).
Check plugin documentation for details. This implements issue #33 .
Added a choice of signals to display:
- input signal possibly mixed with PLL or FLL NCO
- PLL or FLL NCO signal
- Input signal auto-correlation over a fixed length of 4096 samples (actual length depends on sample rate).
In addition refactored to use settings structure similarly to other plugins.
Synchronous AM
Added synchronous AM option to the AM demodulator. Use a PLL to lock to the carrier and mix with the signal. Synchronous AM does not fix all selective fading distortion affecting broadcast on shortwave but does pretty well with the carrier fading which is the most annoying. Hopefully this will bring more comfort to the ears of the broadcast listeners.
Other changes and fixes
- RTL-SDR: fixed inf/sup decimators
- Put all logged or displayed dates in ISO format
- Internal: moving average with variable history size