reusable byte buffers out to the processing chain. This enables the
processing chain to broadcast these buffers back to the decoder for
message assembly and to any running binary recorder.
Updated P25Decoder to be a reusable byte buffer listener. The decoder
will now pass reusable byte buffers down to the message framer for
message processing. This should make the code more efficient since it
can process byte arrays versus handling each individual dibit.
The P25MessageFramer has been updated to be a listener of reusable byte
buffers instead of Dibits, but the actual processing of byte arrays
has to be coded.
Added max recording size to the binary recorder so that it cycles at
500 kB max file size.
buffers. None of the decoders currently support this yet, but the P25
will be updated to provide bitstream output for recording.
Renames the ReusableBuffer class to ReusableFloatBuffer for
consistency.
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.
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.
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.
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.
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.
updates the LSM decoder to follow the same design pattern. Adds LSM
decoder support to the demodulator viewer application. The current
symbol timing gain for LSM is set too high -- is using the C4FM gain
and causes too much fluctuation in the timing error.
error calculator. After increasing the gain for symbol timing, this
new symbol evaluator class seems to track the signal very accurately
despite lots of noise and ISI.
based on the P25 LSM decoder using a costas loop and a gardner detector.
Updates the Demodulator Viewer FX application to add in a symbol chart
and a phase error chart. The decoder won't lock on yet ... still a wip.
produces a significant reduction in memory usage, especially for tuners
like the airspy and hackrf that produce 10/20 MSPS sample rates. This
is observed to be around 66% reduction in peak memory usage and provides
a more stable memory utilization across time reducing stress on the
garbage collector.
Use of these reusable memory buffers will be pushed further down into
the processing chain modules to ensure we keep new object creation
to the lowest levels possible.
