RTLSDR-Airband

RTLSDR Airband is intended for Airband reception and online streaming to services such as liveatc.net

Features

• Multichannel mode - decode up to eight AM channels per dongle (within bandwidth frequency range)
• Scanner mode - decode unlimited number of AM channels with frequency hopping in a round-robin fashion (no frequency range limitations)
• Decode multiple dongles simutaneously
• Auto squelch and Automatic Gain Control
• MP3 encoding
• Stream to Icecast or SHOUTcast server
• Record to local MP3 files (continuously or skipping silence periods)
• Multiple streaming/recording destinations per channel

Performance

x86

• ~4% per dongle on i5-2430m at 2.1 GHz

Raspberry Pi

• FFT using Broadcom Videocore IV GPU
• No overclock required when using 1 dongle plus another dongle running dump1090
• Turbo overclock setting recommended on RPi V1 when using 2 dongles (no overclocking is necessary on RPi V2)

Other ARMv7-based platforms

• FFT using main CPU
• Tested on Cubieboard1 - ~50% CPU when using 1 dongle

Demo

Building

Windows using VS Express 2013 for Desktop

WARNING: Windows build is currently unmaintained and might not work

Getting/Building prerequisites

FFTW3

• Download fftw-3.3.4-dll32.zip from http://www.fftw.org/install/windows.html
• Start the VS2013 x86 Native Tools Command Prompt
• Run lib /def:libfftw3f-3.def to get libfftw3f-3.lib
• Place the lib into win32/lib
• Place fftw3.h into win32/include
• Place libfftw3f-3.dll into the root folder

libogg and libvorbis

• Download libogg-1.3.1.zip and libvorbis-1.3.4.zip from http://www.xiph.org/downloads/
• Extract both zip files in the same folder
• Rename libogg-1.x.x to libogg
• Open libogg/win32/libogg_static.sln
• Change to "Release" and build libogg_static
• Open libvorbis-1.x.x/win32/VS2010/vorbis_static.sln
• Change to "Release" and build libvorbis_static (NOT the highlighted libvorbisfile)
• Copy both the generated .libs to win32/lib
• Copy libogg/includes/ogg (the folder) to win32/include
• Copy libvorbis-1.x.x/includes/vorbis (the folder) to win32/include

libmp3lame

• Download from http://sourceforge.net/projects/lame/files/lame/3.99/
• Open vc_solution/vc9_lame.sln
• Change the Configuration to ReleaseSSE2
• (optional) Right click libmp3lame-static and open Properties... C/C++... Code Generation... Enable Enhanced Instruction Set... Advanced Vector Instructions
• Build libmp3lame-static
• Copy output/ReleaseSSE2/libmp3lame-static.lib and libmpghip-static.lib to win32/lib
• Copy include/lame.h to win32/include

librtlsdr

• Download from http://sdr.osmocom.org/trac/wiki/rtl-sdr (search word: "pre-built")
• Copy rtl-sdr-release/rtl-sdr.h and rtl-sdr_export.h to win32/includes
• Copy rtl-sdr-release/x32/rtlsdr.lib to win32/lib
• Copy rtl-sdr-release/x32/rtlsdr.dll and libusb-1.0.dll to root folder

pthreads

• Download from ftp://sourceware.org/pub/pthreads-win32/
• Extract Pre-built.2 to the same folder where libogg and libvorbis are located
• Copy Pre-built.2/lib/x86/pthreadVCE2.lib to win32/lib
• Copy Pre-built.2/dll/x86/pthreadVCE2.dll to root folder

libshout

• This is the most complicated one
• Download from http://www.icecast.org/download.php
• Extract libshout to the same folder where libogg and libvorbis are located
• Go to libshout-2.x.x/include/shout and rename shout.h.in to shout.h
• Open libshout/win32/libshout.dsw
• Change to "Release"... and then open project properties
• On the General page change Character Set to Use Unicode Character Set
• Go to C/C++... edit Additional Include Directories
• Add ../../libogg/include, ../../libvorbis-1.x.x/include and ../../Pre-built.2/include
• Go to C/C++... Preprocessor... edit Preprocessor Definitions
• Add HAVE_SYS_TIMEB_H and HAVE_FTIME
• Try to build, you should get errors
• One of the error is "error C1083: Cannot open include file: 'compat.h': No such file or directory"
• Double click on it and change that line from #include <compat.h> to #include <os.h>
• Build again
• Copy win32/Release/libshout.lib to win32/lib
• Copy include/shout (the folder) to win32/include

Building this project

• Browse into win32 and open the solution
• Simply build solution or click the "Start Local Windows Debugger" button

Linux (Raspbian)

• Install RTLSDR library (http://sdr.osmocom.org/trac/wiki/rtl-sdr):

   sudo apt-get update
   sudo apt-get install git gcc autoconf make libusb-1.0-0-dev
   cd
   git clone git://git.osmocom.org/rtl-sdr.git
   cd rtl-sdr/
   autoreconf -i
   ./configure
   make
   sudo make install
   sudo ldconfig
   sudo mv $HOME/rtl-sdr/rtl-sdr.rules /etc/udev/rules.d/rtl-sdr.rules
  

• Blacklist DVB drivers to avoid conflict with SDR driver - before connecting the USB dongle create file /etc/modprobe.d/dvb-blacklist.conf with text editor (eg. nano) and add the following lines:

   blacklist r820t
   blacklist rtl2832
   blacklist rtl2830
   blacklist dvb_usb_rtl28xxu
  

• Download a release tarball from from https://github.com/szpajder/RTLSDR-Airband/releases and unpack it. Example:

   tar xvfz RTLSDR-Airband-1.0.0.tar.gz
   cd RTLSDR-Airband-1.0.0
  

  Alternatively you can pull the latest code from git (but please be aware that it might be experimental, buggy, or at least, untested):

   git clone https://github.com/szpajder/RTLSDR-Airband.git
   cd RTLSDR-Airband/
  

• Install necessary dependencies:

   sudo apt-get install libmp3lame-dev libvorbis-dev libshout-dev libconfig++-dev
  

• Set the PLATFORM environment variable (to indicate your hardware platform) and run make. For example, to build a binary for RPi version 1 (ARMv6 CPU, Broadcom VideoCore GPU) type the following:

   PLATFORM=rpiv1 make
  

  Building for RPi V2 (ARMv7 CPU, Broadcom VideoCore GPU):

   PLATFORM=rpiv2 make
  

  Building for other ARMv7-based platforms without VideoCore GPU, eg. Cubieboard (FFTW3 library is needed in this case):

   sudo apt-get install libfftw3-dev
   PLATFORM=armv7-generic make
  

  Building for generic x86 CPU (FFTW3 library is needed in this case):

   sudo apt-get install libfftw3-dev
   PLATFORM=x86 make
  

• Install the software:

   make install
  

  By default, the binary is installed to /usr/local/bin/rtl_airband.

• Edit the configuration file to suit your needs. See chapter "Configuring" below.

• You need to run the program with root privileges - for example:

   sudo /usr/local/bin/rtl_airband
  

  The program runs as a daemon (background process) by default, so it may look like it has exited right after startup. Diagnostic messages are printed to syslog (on Raspbian they are directed to /var/log/messages by default).

• If you wish to start the program automatically at boot, you can use example startup scripts from init.d/ subdirectory. Example for Debian / Raspbian:

   sudo cp init.d/rtl_airband-debian.sh /etc/init.d/rtl_airband
   sudo chmod 755 /etc/init.d/rtl_airband
   sudo update-rc.d rtl_airband defaults
  

Configuring

By default, the configuration is read from /usr/local/etc/rtl_airband.conf file. Refer to rtl_airband.conf.example for the description of the format. You can copy this file to /usr/local/etc/rtl_airband.conf and edit it to suit your needs (make install does this, unless you already have your own config file installed).

Old versions of RTLSDR-Airband used a simple flat config.txt file. This is no longer supported. You have to rewrite your config file to the new syntax - or just use a small utility convert_cfg which is included in the util subdirectory:

cd util
make
./convert_cfg /path/to/old/config.txt /path/to/new/rtl_airband.conf

Review the rtl_airband.conf file and move it to /usr/local/etc before launching rtl_airband:

sudo mv /path/to/new/rtl_airband.conf /usr/local/etc

Command line options

rtl_airband accepts the following command line options:

-h                      Display this help text
-f                      Run in foreground, display textual waterfalls
-c <config_file_path>   Use non-default configuration file

Troubleshooting

• If the program fails to start on RPi: check if device node /dev/vcio exists:

  pi@mypi ~ $ ls -l /dev/vcio crw-rw---T 1 root video 249, 0 Jan 1 1970 /dev/vcio

  If you get "No such file or directory", then create it:

  sudo mknod /dev/vcio c 249 0

  Older Raspbian kernels (before 4.0) used 100 as a major number instead of 249, so be sure you are creating the node correctly. You can check the correct major number with this command:

  pi@mypi:~# grep vcio /proc/devices 100 vcio

In this case, /dev/vcio must be created this way:

 sudo mknod /dev/vcio c 100 0

• When the program is running in scan mode and is interrupted by a signal (eg. ctrl+C is pressed when run in foreground mode) it crashes with segmentation fault or spits out error messages similar to these:

  r82xx_write: i2c wr failed=-1 reg=1a len=1 r82xx_set_freq: failed=-1 rtlsdr_demod_write_reg failed with -1 rtlsdr_demod_read_reg failed with -7

  This is due to a bug in libusb versions earlier than 1.0.17. Upgrade to a newer version.

License

Copyright (C) 2015 Tomasz Lemiech szpajder@gmail.com

Based on original work by Wong Man Hang microtony@gmail.com

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program 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 General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Open Source Licenses

###fftw3

• Copyright (c) 2003, 2007-14 Matteo Frigo
• Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
• GNU General Public License Version 2

###gpu_fft BCM2835 "GPU_FFT" release 2.0 Copyright (c) 2014, Andrew Holme. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

###libmp3lame

•  Copyright (c) 1999 Mark Taylor
  

•  Copyright (c) 2000-2002 Takehiro Tominaga
  

•  Copyright (c) 2000-2011 Robert Hegemann
  

•  Copyright (c) 2001 Gabriel Bouvigne
  

•  Copyright (c) 2001 John Dahlstrom
  

• GNU Library General Public License Version 2

###libogg Copyright (c) 2002, Xiph.org Foundation

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

• Neither the name of the Xiph.org Foundation nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

###librtlsdr

• Copyright (C) 2012 by Steve Markgraf steve@steve-m.de
• GNU General Public License Version 2

###libshout

• Copyright (C) 2002-2004 the Icecast team team@icecast.org
• GNU Library General Public License Version 2

###libvorbis Copyright (c) 2002-2008 Xiph.org Foundation

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

• Neither the name of the Xiph.org Foundation nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

###libconfig Copyright (C) 2005-2014 Mark A Lindner

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License 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.