actively decoding, but no call or data is being transmitted. This is
primarily used for P25 channels when TDU Link Control messages are
being transmitted in between voice or data transmissions on a channel.
Updated several of the P25 decoder state message processing sections to
keep the channel state UI updated with current call identifiers and
states.
Hard-coded channel state colors to remove inefficiency in the way that
channel state coloration was being handled.
the lost connection timeout from default of 60 seconds down to 5 seconds
so that the connection state updates more quickly. Removed complex
error handling and replaced with a simpler approach to catch an error
and disconnect and then attempt a reconnect.
Added new 'Network Unavailable' error state that detects when the network
connection is unavaialable.
Updated the icecast metadata updater to close the TCP session after
successfully writing metadata to the socket.
and auto-correction for R820T tuners.
-Updated TunerModel and TunerViewPanel to add 2 new columns to
display the current tuner's PPM setting and (when available) the
measured frequency error averaged over 5 second intervals provided by
certain decoders (e.g. P25 C4FM and LSM). Frequency error value from
P25 decoders is provided from the Costas Loop PLL once 2 or more P25
message sync events have been observed in a short period.
-Updated R820T tuner to auto-correct PPM when measured frequency error
exceeds the +/- 0.4PPM threshold for a period of 30 seconds or more.
Feature can be enabled/disabled by user in the tuner editor panel.
Resolved several issues with P25 C4FM/LSM decoders that was impacting
performance related to channel misalignment from tuner PPM offsets.
Resolves an issue with the previous implementation where the tuner
editor was being refreshed repeatedly to update the lock state for the
tuner, rendering the editor almost completely unusable.
Now updates only the frequency control and the sample rate control to
reflect the tuner's lock state.
Adds capability to disable spectral display.
Adds right-click context
menu items to disable display and/or reenable display by selecting
another tuner.
Adds view menu items to disable spectral display or show a tuner.
Persists spectral display enabled state across application run sessions.
The C4FM and LSM decoders were issuing a PLL reset with each new
channel that was allocated, causing any existing decoding channels to
be disrupted. Decoding re-sync delays or inability to recapture the
signal for decoding would likely result as the tuner's overall PPM
caused misadjustment in the channel.
Resolved a NPE that was occurring in the FrequencyController for
sample rate changes.
sample rates.
Resolves issue in PolyphaseChannelManager responding to sample rate
changes in the tuner. The manager now recreates the channelizer when
needed if the tuner's sample rate has changed since the last time the
channelizer was used.
Updates the Tuner selection view to reflect tuner lock state. Updates
the tuner editors to enable/disable frequency controller and sample
rate controls according to the tuner's lock state.
Refactors a MixerReader instance from the RealMixerSource so that it
can be reused for both real and complex data outputs.
Updates RealMixerSource to use refactored MixerReader and use a default
sample rate of 8 kHz.
Updates the ComplexMixer to use the refactored MixerReader.
Updates the FCD 1/2 tuners for compatibility with the new ComplexMixer.
Removes several unused classes.
Fleetsync II decoder to use it. Adds instrumented version of the decoder
and a new Fleetsync2 FX pane to the DemodulatorViewerFX tool.
Note: the remaining AFSK-1200 based decoders will all be ported to use
this new AFSK1200 decoder (MDC1200, Tait1200, LowJack1200).
Deprecates the Listener<Boolean> interface method in the MessageFramer
to optimize for primitive booleans and reduce impact on memory. Will
remove this interface once the AFSK1200 decoders are updated.
channelizer sub-system is functionally complete.
Updated the channelizer and synthesizer filter design methods to use a
Kaiser windowed Nyquist filter. Updated the synthesizer filter design
to use a new cutoff frequency of 105% of the channel bandwidth to
resolve a slight dip in the synthesized channel gain at the channel
union region.
Updated the 2 channel output processor to use a low-pass filter that
is designed for the runtime channel sample rate versus hard-coded 12.5
khz.
Testing and redesign continues ...
filter structure. Updated the channel results array buffer to produce
reusable buffers.
This has dropped the overall memory usage considerably when profiling.
Resolved issue in the processing chain where polyphase channel sources
were not being stopped and were stacking up in memory.
that is currently up/down converting the signal of interest, but the
synthesizer is not correctly combining the original two channels.
Some experimentation with the tap count for the channelizer indicates
that we can cut the tap count in half and still have decent decoding
on the P25 decoder when paired to an aligned channelized output. The
2-channel synthesized output decodes partially, but needs more work.
Resolved issue with channel gain in the channelizer that was making the
sample values so small that they were registering as zero when converted
from float to 16-bit int value in the complex wave recorder.
was not computationally feasible with my 3rd Gen i7 processor running
and airspy at 10 MHz. Restructured the polyphase channelizer to use
vector iteration structures that the JDK 9 JIT compiler can translate
into SIMD instructions. Separated the IFFT processing from the filter
process so that they can be executed on separate threads and this allows
the processing to occur real time.
P25 C4FM decoding at 25 kHz channel sample rate using an airspy
10MHz sample stream seems to be working nicely with ~25% CPU usage and
~300 to 500 MB memory usage. Incremental (parallel) channel decoding
should have a minimal increase in CPU loading since all of the 12.5 kHz
channels are available in the polyphase channelizer and the only
additional workload is the decoding of the 25 kHz sample stream.
There is still an issue with stopping channels and the channelizer keeps
processing, and occasionally when starting traffic channels something
deadlocks and causes out of memory.
adds Feed forward gain support to the C4FM DQPSK demodulator which seems
to improve output from the interpolating sample buffer at each symbol
period. Updates the symbol timing gain for C4FM to decrease the gain a
bit since the feed forward gain is providing a better interpolated symbol.
