It is implementation of DAB/DAB+ software decoder. Input samples could be retrived from file or tuner (librtlsdr). Output sound could be save to file or played via GStreamer.
Developed by students of AGH-UST in Department of Telecommunications.
Project webpage sdr.kt.agh.edu.pl
Tested on Ubuntu 14.x, 16.x and other. Need: gcc and a few standard libraries. libsdrdab has it's own implementation of librtlsdr. Do not need librtlsdr, do not conflict with installed librtlsdr.
- download code
- unpack
- install dependencies: ./sdrtool install-deps
- build: ./sdrtool build Release
- run: ./build/bin/sdrdab-cli
library is located in ./build/src/sdrdab/libsdrdab.a cli-reference-implemenation is located in ./build/bin/sdrdab-cli
Installation is not supported so far.
This implementation include unittests. They are only for developing purpose. Steps necessary to perform unittests:
- ./sdrtool download-ut # download raw data
- ./sdrtool matlab # generate input and output for unittests
- ./sdrtool build Unittest # build library with unittests
- ./sdrtool run-unittests # perform all unittests
Unittests includes DAB/DAB+ decoder (in Matlab) written by Michael Hoin ZHAW Zürcher Hochschule für Angewandte Wissenschaften and extended by Tomasz Zielinski AGH-UST Telecommunications Department. This code is used to generate input and output (truth) data for unittests. You need Matlab to perform unittests.
It is possible to download some data (./sdrtool download-*) necessary for unittest and helpful for testing library. It consists of recordings come from publicly available and uncoded signal. Copyrights to pieces registered at that time belong to their authors. Recordings were not modified (apart from format conversion). Recordings can only be used in order to test the library; in particular further publishing or public reproducing is not allowed.
- debug AGC
- TEQ - time equalizer
- resampling (fs) made by means of remodulate+FEQ+interpolation after FFT
- custom resampling (fs), only necessary parts (like FFT in MSC), remove RingBuffer
- resampling == own thread? CPU vector (SSE/NEON) optimization?
- implementation of convolutional code simpler than Viterbi decoder (hard-decision, BCJR, soft-decision)
- smart algorithm for convolutional decoder choise (based on SNR?), independent FIC and MSC?
- USRP supports (input signal), other hardware?
- extend input file support: float, double, uint16_t/int16_t, automatic (smart) detection
- decompress to raw samples (get rid of GStreamer and other framework), make resampling in time domain
- decoding extra data (images, etc…)
- ReedSolomon custom implementation (optimized to DAB)
- RS smart on/off (depends on previous errors, CRC and firecode)
- support Rayleigh fading channels
- memory optimization (smaller buffer, adaptive buffers?)
- improve system delay (scheduler optimization), system should maintain 200-500 ms delay
- FIC SNR improvement: CIF’s repeats (energy could be accumulated before Viterbi and thus improve SNR)
- decode many (all) audio streams simultaneously
- FIle2FIle should not skip frames from beginning of stream
- extensive unittest: all possible bitstreams, types, modes (I, II, III and IV), additional data and various configuration of multiplex
- test and tune to mobile case (Rayleigh channel)
- improve GUI (with vizualization: spectrum, SNR, errors, extra data (images), etc...)
- merge arm-development into development (extra CMake, stats generator, performance improvements, Neon instructions support, psd and snr estimation)
- performance (time) test integrated with build (per method on release build)
- performance (erorr) test integrated with build - parameters: SNR, fc, fs
- ARM (RaspberyPI v2)
- ARM Android NDK/SDK
- x86 Windows
- x86 MacOS: more test, build is already done
- refactoring DataFeeder (too complex)
- refactoring AudioDecoder (too complex?)
- package for Linux (Ubuntu and other distros)
- all code (including library) on LGPL license
- integration with vlc/mplayer/kino/kodi plugin/other media player
- improve UnitTest for depuncturer (implement testing code for all cases)
- recover broken UnitTest
- improve Synchronizer (chose algorithm, remove or repair dependencies for remodulation)
- test synchronizer for weak signal (+-10 levels for 8-bit input sample)
- refactoring DataDecoder::DePuncturerProcess()
- add UnitTest for audio verification (all channels, different modes, various modes, etc...)
- decode NULL
- software MIMO (check if it's possible to use two or more RTL dongle, synchronize and use MIMO algorithms)
- calculate SNR from PR (3rd algorithm for SNR calculation)
- analyze algorithm for SNR calculation from Demodulator
- refactoring fs and fc drifts
- implement time signatures/counter for signal in all classes (allows for precise synchronization)
- performance (time) test integrated with build (per method on release build)
- performance (error) test integrated with build - parameters: SNR, fc, fs
- DataFeeder refractoring (too complex)
- AudioDecoder refractoring (too complex)
- package for Linux (Ubuntu and other distros)
- all code (including library) on LGPL license
- ARM (RaspberyPI v2)
- ARM Android NDK/SDK
- x86 Windows
- x86 MacOS: more test, build is already done
- integration with vlc/mplayer/kino/kodi plugin/other media players
- merge arm-development (2015) into development (extra CMake, stats generator, performance improvements, Neon instructions support, psd and snr estimation)
- like eti-tools
- supports USRP (real-time)
- supports simulation of various disturbances: AWGN, NBI, fading channels, rayleigh fading channels, etc...
2016:
- Tomasz P. Zieliński (tzielin@agh.edu.pl)
- Jarosław Bułat (kwant@agh.edu.pl) <---- contact person
- Jakub Bernady
- Szymon Czubak
- Szymod Dawidow
- Alicja Gęgotek
- Joanna Gniadek
- Michał Jurczak
- Paweł Kazimierowicz
- Przemysław Piątek
- Anna Radoszek
- Marek Rzepecki
- Mikołaj Suliga
- Bartosz Stopa
- Marcin Trebunia
- Piotr Wierzbicki
- Adrian Włosiak
- Łukasz Włosowicz
- Mateusz Wnętrzak
- Kacper Żuk
2015:
- Tomasz P. Zieliński (tzielin@agh.edu.pl)
- Jarosław Bułat (kwant@agh.edu.pl) <---- contact person
- Michał Babiuch (babiuch.michal@gmail.com)
- Ernest Biela
- Szymon Dąbrowski
- Piotr Jaglarz
- Adrian Karbowiak
- Sebastian Leśniak
- Rafał Palej
- Kacper Patro
- Michał Rybczyński
- Dawid Rymarczyk
- Michał Rzepka (mrzepka@student.agh.edu.pl)
- Krzysztof Szczęsny (kaszczesny@gmail.com)
- Wojciech Szmyd
- Paweł Szulc (pawel_szulc@onet.pl)
- Jan Twardowski
- Łukasz Wysogląd
- Kacper Zych (kacperzych@wp.pl)
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA