Commit Graph

17 Commits

Author SHA1 Message Date
Denny Sheirer
4b806ecfde #36 NBFM squelch control. Updates NBFM decoder to incorporate squelch control. Squelch is a configuration item and also available to adjust at runtime with new 'Channel' tab in Now Playing window. All decoders were updated to produce continuous channel power (dB) measurements that are displayed in the Channel tab's new Power Meter. (#1100)
Co-authored-by: Dennis Sheirer <dsheirer@github.com>
2021-11-14 06:59:58 -05:00
Denny Sheirer
7eec82deee #6 DMR Decoder (#947)
* #6 DMR decoder feature - work in progress

* #6 DMR Decoder.

* #6 DMR Decoder.  Code review updates.

Co-authored-by: Zhenyu Mao <maozhenyu@foxmail.com>
Co-authored-by: Denny <denny@denny-desktop>
2020-10-12 04:57:59 -04:00
robekl
39f6d6c831 Performance improvements (#746)
* Misc minor performance improvements

* Use more concise loop syntax

* Use more concise Collection sort syntax

* Use StringUtils pad methods

* Optimize some loops and double-map-lookups

* Optimize array instantiation

There are two styles to convert a collection to an array: either
using a pre-sized array (like c.toArray(new String[c.size()])) or
using an empty array (like c.toArray(new String[0]).

In older Java versions using pre-sized array was recommended,
as the reflection call which is necessary to create an array
of proper size was quite slow. However since late updates of
OpenJDK 6 this call was intrinsified, making the performance
of the empty array version the same and sometimes even better,
compared to the pre-sized version. Also passing pre-sized array
is dangerous for a concurrent or synchronized collection as
a data race is possible between the size and toArray call
which may result in extra nulls at the end of the array,
if the collection was concurrently shrunk during the operation.

* Cleanup string concatenation

* Use EnumMap where possible

* Use FastMath instead of Math

* Initialize complex things only once

* Reduce method size to aloow more JIT inlining

* remove map of short->float

* Move field to local variable

* Cleanup Map lookup

Co-authored-by: Rob Ekl <xwq876@zebra.com>
2020-04-25 07:57:56 -04:00
Denny Sheirer
f934676bd0 #296 APCO25 Phase II Decoder Implementation (#589)
P25 Phase 2 Decoder implementation.
2019-11-17 06:56:52 -05:00
Denny
570321da3e Implements a complex sample delay buffer integrated into the tuner
channel manager so that channel source requests can have a start
timestamp specified and the channel can be preloaded with samples from
the delay buffer.  If no timestamp is specified, current time is assumed.

This feature requires corresponding updates to any decoder that wishes
to implement the timestamped sample preloading functionality.
2018-09-09 08:46:21 -04:00
Denny
0c47efea03 Resolves #373 - Adds support for Tuner frequency error PPM monitoring
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.
2018-07-29 10:48:29 -04:00
Denny
e88944e53d Updates all reusable buffer queues to automatically set the user count
to 1 on all provided buffers by default.
2018-07-01 07:08:52 -04:00
Denny
a898be265f [WIP] Updates the LTR-Standard and LTR-Net decoders to use a new LTR
decoder with a zero-crossing symbol timing error detector.  The new
decoder is optimized for 8 kHz FM demodulated audio produced by the
AudioModule.
2018-06-02 08:47:48 -04:00
Denny
60ffb18cd9 39 [WIP] cleans up the reusable buffers and creates both real and
complex variants.
2018-03-25 09:13:03 -04:00
Denny
c36f6901af 39 - Adds P25/LSM support to the DemodulatorViewerFX application and
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.
2018-03-24 11:03:18 -04:00
Denny
bfaacb309d 39 - WIP - incorporates the latest P25 C4FM decoder from master and
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.
2018-03-24 06:59:41 -04:00
Denny
c3b405a752 Merge branch 'master' into 39-polyphase-channelizer
# Conflicts:
#	src/main/java/io/github/dsheirer/buffer/FloatCircularBuffer.java
#	src/main/java/io/github/dsheirer/dsp/filter/FilterFactory.java
#	src/main/java/io/github/dsheirer/dsp/filter/design/FilterView.java
#	src/main/java/io/github/dsheirer/dsp/filter/design/FilterViewer.java
#	src/main/java/io/github/dsheirer/dsp/filter/fir/complex/ComplexFIRFilter.java
#	src/main/java/io/github/dsheirer/dsp/gain/ComplexFeedForwardGainControl.java
#	src/main/java/io/github/dsheirer/dsp/mixer/Oscillator.java
#	src/main/java/io/github/dsheirer/dsp/psk/LSMDemodulator.java
#	src/main/java/io/github/dsheirer/module/decode/Decoder.java
#	src/main/java/io/github/dsheirer/module/decode/DecoderFactory.java
#	src/main/java/io/github/dsheirer/module/decode/p25/P25Decoder.java
#	src/main/java/io/github/dsheirer/module/decode/p25/P25_C4FMDecoder.java
#	src/main/java/io/github/dsheirer/module/decode/p25/P25_LSMDecoder.java
#	src/main/java/io/github/dsheirer/source/tuner/TunerChannelSource.java
#	src/main/java/io/github/dsheirer/source/tuner/TunerModel.java
#	src/main/java/io/github/dsheirer/source/tuner/TunerSourceEditor.java
#	src/main/java/io/github/dsheirer/spectrum/ChannelSpectrumPanel.java
2018-03-18 05:19:33 -04:00
Denny
dda37a1198 330 WIP - updates the demodulator viewer with an eye diagram and symbol
chart.  Testing various configurations to see which yields the best
PLL and symbol timing locks.
2018-02-18 16:20:45 -05:00
Denny
1406d5576a 330 - Adds new JavaFX implementation of the demodulator viewer applicaiton
with initial support for playback control and I/Q sample axis viewing.
2018-02-11 10:16:50 -05:00
Denny
f2f2c92afe [WIP] Implements reusable sample buffers across all components. This
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.
2018-02-03 10:05:16 -05:00
Denny
236df8f3f4 Merges from master branch. 2017-12-27 10:10:51 -05:00
Denny
9316599dec Updates pull request from Roman Tsypuk to convert the build system from
ant to gradle.  Removes linux and windows application launch scripts and
produces an executable jar with all resources included.
2017-12-17 07:28:06 -05:00