SDR (Software Defined Radio) » rtl-sdr

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= rtl-sdr =

DVB-T dongles based on the Realtek RTL2832U can be used as a cheap SDR, since the chip allows transferring the raw I/Q samples to the host, which is officially used for DAB/DAB+/FM demodulation. The possibility of this has been discovered by the V4L/DVB kernel developer [http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/44461/focus=44461 Antti Palosaari].

== Specifications ==

The RTL2832U outputs 8-bit I/Q-samples, and the highest theoretically possible sample-rate is 3.2 MS/s, however, the highest sample-rate without lost samples that has been tested so far is 2.8 MS/s. The frequency range is highly dependent of the used tuner, '''dongles that use the Elonics E4000 offer the widest possible range (64 - 1700 MHz with a gap from approx. 1100 - 1250 MHz)'''. When used out-of-spec, a tuning range of approx. 50 MHz - 2.2 GHz is possible (with gap).

== Supported Hardware ==

The following devices are known to work fine with RTLSDR software:

||'''VID'''||'''PID'''||'''tuner'''||'''device name'''||

||0x0bda||0x2832||all of them||Generic RTL2832U (e.g. hama nano)||

||0x0bda||0x2838||E4000||ezcap USB 2.0 DVB-T/DAB/FM dongle||

||0x0ccd||0x00a9||FC0012||Terratec Cinergy T Stick Black (rev 1)||

||0x0ccd||0x00b3||FC0013||Terratec NOXON DAB/DAB+ USB dongle (rev 1)||

||0x0ccd||0x00d3||E4000||Terratec Cinergy T Stick RC (Rev.3)||

||0x0ccd||0x00e0||E4000||Terratec NOXON DAB/DAB+ USB dongle (rev 2)||

||0x185b||0x0620||E4000||Compro Videomate U620F||

||0x185b||0x0650||E4000||Compro Videomate U650F||

||0x1f4d||0xb803||FC0012||GTek T803||

||0x1f4d||0xc803||FC0012||Lifeview LV5TDeluxe||

||0x1b80||0xd3a4||FC0013||Twintech UT-40||

||0x1d19||0x1101||FC2580||Dexatek DK DVB-T Dongle (Logilink VG0002A)||

||0x1d19||0x1102||?||Dexatek DK DVB-T Dongle (MSI DigiVox mini II V3.0)||

||0x1d19||0x1103||FC2580||Dexatek Technology Ltd. DK 5217 DVB-T Dongle||

||0x0458||0x707f||?||Genius TVGo DVB-T03 USB dongle (Ver. B)||

||0x1b80||0xd393||FC0012||GIGABYTE GT-U7300||

||0x1b80||0xd394||?||DIKOM USB-DVBT HD||

||0x1b80||0xd395||FC0012||Peak 102569AGPK||

||0x1b80||0xd39d||FC0012||SVEON STV20 DVB-T USB & FM||

If you don't know where to buy one or if you are just looking for a trustworthy source, try http://shop.sysmocom.de/t/software-defined-radio

People over at reddit [http://www.reddit.com/r/RTLSDR/comments/s6ddo/rtlsdr_compatibility_list_v2_work_in_progress/ are collecting a list (v2)] of other devices that are compatible.

Other dongles based on the RTL2832U might be added in the future as well.

This is the PCB of the ezcap-stick:[[br]][[br]]

[[Image(ezcap_top.jpg,50%)]][[br]]

More pictures can be found [http://www.steve-m.de/pictures/rtl-sdr/ here].

== Software ==

rtl-sdr is a commandline tool that can initialize the RTL2832, tune to a given frequency, and record the I/Q-samples to a file.

The code can be checked out with:

{{{

git clone git://git.osmocom.org/rtl-sdr.git

}}}

It can also be browsed on http://cgit.osmocom.org/cgit/rtl-sdr/

If you are going to "fork it on github" and enhance it, please contribute back and submit your patches to: osmocom-sdr at lists.osmocom.org

A [http://cgit.osmocom.org/cgit/gr-osmosdr/ GNU Radio source block] for [http://sdr.osmocom.org/trac/ OsmoSDR] '''and rtlsdr''' is available. '''Please install a recent gnuradio (>= v3.5.3) in order to be able to use it.''' 

=== Building the software ===

==== rtlsdr library & capture tool ====

'''You have to install development packages for libusb1.0''' and can either use cmake or autotools to build the software.

Please note: prior pulling a new version from git and compiling it, please do a "make uninstall" first to properly remove the previous version.

Building with cmake:

{{{

cd rtl-sdr/

mkdir build

cd build

cmake ../

make

sudo make install

sudo ldconfig

}}}

In order to be able to use the dongle as a non-root user, you may install the appropriate udev rules file by calling cmake with -DINSTALL_UDEV_RULES=ON argument in the above build steps.

{{{

cmake ../ -DINSTALL_UDEV_RULES=ON

}}}

Building with autotools:

{{{

cd rtl-sdr/

autoreconf -i

./configure

make

sudo make install

sudo ldconfig

}}}

The built executables (rtl_sdr, rtl_tcp and rtl_test) can be found in rtl-sdr/src/.

In order to be able to use the dongle as a non-root user, you may install the appropriate udev rules file by calling

{{{

sudo make install-udev-rules

}}}

[attachment:RelWithDebInfo.zip pre-built Windows version] using libusb 1.0.9 and pthreads-win32 cvs

==== Gnuradio Source ====

'''The gnuradio source requires the rtl-sdr package and a recent gnuradio (>= v3.5.3) to be installed.'''

The source supports direct device operation as well as a tcp client mode when using the rtl_tcp utility as a spectrum server.

Please note: prior pulling a new version from git and compiling it, please do a "make uninstall" first to properly remove the previous version.

Please note: you always should build & '''install the latest version of the dependencies (librtlsdr in this case)''' before trying to build the gr source.

Building with cmake:

{{{

git clone git://git.osmocom.org/gr-osmosdr

cd gr-osmosdr/

mkdir build

cd build/

cmake ../

make

sudo make install

sudo ldconfig

}}}

NOTE: The source block (osmosdr/rtlsdr Source) will appear under 'Sources' category in GRC menu.

For initial tests we recommend the multimode receiver gnuradio companion flowgraph (see "Known Apps" table below).

You may find more detailed installation instructions in this recent [http://blog.opensecurityresearch.com/2012/06/getting-started-with-gnu-radio-and-rtl.html tutorial].

==== Automated installation ====

Marcus D. Leech has kindly integrated the forementioned build steps into his gnuradio installation script at [http://www.sbrac.org/files/build-gnuradio]. This is the most user-friendly option so far.

=== Usage ===

==== rtl_sdr ====

Example: To tune to 392.0 MHz, and set the sample-rate to 1.8 MS/s, use:

{{{

./rtl_sdr /tmp/capture.bin -s 1.8e6 -f 392e6

}}}

to record samples to a file or to forward the data to a fifo.

If the device can't be opened, make sure you have the appropriate rights to access the device (install udev-rules from the repository, or run it as root).

==== rtl_tcp ====

Example:

{{{

rtl_tcp -a 10.0.0.2 [-p listen port (default: 1234)]

Found 1 device(s).

Found Elonics E4000 tuner

Using Generic RTL2832U (e.g. hama nano)

Tuned to 100000000 Hz.

listening...

Use the device argument 'rtl_tcp=10.0.0.2:1234' in OsmoSDR (gr-osmosdr) source

to receive samples in GRC and control rtl_tcp parameters (frequency, gain, ...).

}}}

use the rtl_tcp=... device argument in gr-osmosdr source to receive the samples in GRC and control the rtl settings remotely.

This application has been successfully crosscompiled for ARM and MIPS devices and is providing IQ data in a networked ADS-B setup at a rate of 2.4MSps. The gr-osmosdr source is being used together with an optimized gr-air-modes version (see Known Apps below).

You can find a Makefile for OpenWRT [http://steve-m.de/projects/rtl-sdr/Makefile here].

A use case is described [https://sites.google.com/site/embrtlsdr/ here].

==== rtl_test ====

To check the possible tuning range (may heavily vary by some MHz depending on device and temperature), call

{{{

rtl_test -t

}}}

To check the maximum samplerate possible on your machine, type (change the rate down until no sample loss occurs):

{{{

rtl_test -s 3.2e6

}}}

A samplerate of 2.4e6 is known to work even over tcp connections (see rtl_tcp above). A sample rate of 2.88e6 may work without lost samples but this may depend on your PC/Laptop's host interface.

== Using the data ==

To convert the data to a standard cfile, following GNU Radio Block can be used:[[br]]

[[br]][[Image(rtl2832-cfile.png)]][[br]][[br]]

The GNU Radio Companion flowgraph (rtl2832-cfile.grc) is attached to this page. It is based on the FM demodulation flowgraph posted by Alistair Buxton [http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/44461/focus=44525 on this thread].

Please note: for realtime operation you may use fifos (mkfifo) to forward the iq data from the capture utility to the GRC flowgraph.

You may use any of the the following gnuradio sources (they are equivalent):

[[br]][[br]][[Image(osmosource.png)]][[br]]

What has been successfully tested so far is the reception of [https://www.cgran.org/browser/projects/multimode/trunk Broadcast FM and air traffic AM] radio, [http://tetra.osmocom.org/ TETRA], [http://gmr.osmocom.org/ GMR], [http://svn.berlin.ccc.de/projects/airprobe/ GSM], [https://www.cgran.org/wiki/gr-air-modes ADS-B] and [https://github.com/smunaut/osmo-pocsag POCSAG].

Tell us your success story with other wireless protocols in ##rtlsdr channel on freenode IRC network.

== Known Apps ==

The following 3rd party applications and libraries are successfully using either librtlsdr directly or the corresponding gnuradio source (gr-osmosdr):

||'''Name'''||'''Type'''||'''Author'''||'''URL'''||

||gr-pocsag||GRC Flowgraph||Marcus Leech||[https://www.cgran.org/browser/projects/gr-pocsag/trunk]||

||multimode RX (try first!)||GRC Flowgraph||Marcus Leech||[https://www.cgran.org/browser/projects/multimode/trunk]||

||simple_fm_rvc||GRC Flowgraph||Marcus Leech||[https://www.cgran.org/browser/projects/simple_fm_rcv/trunk]||

||python-librtlsdr||Python Wrapper||David Basden||[https://github.com/dbasden/python-librtlsdr]||

||pyrtlsdr||Python Wrapper||Roger||[https://github.com/roger-/pyrtlsdr]||

||rtlsdr-waterfall||Python FFT GUI||Kyle Keen||[https://github.com/keenerd/rtlsdr-waterfall]||

||Wireless Temp. Sensor RX||Gnuradio App||Kevin Mehall||[https://github.com/kevinmehall/rtlsdr-433m-sensor]||

||!QtRadio||SDR GUI||Andrea Montefusco et al.||[http://napan.ca/ghpsdr3/index.php/RTL-SDR]||

||gqrx (fork)||SDR GUI||Alexandru Csete||[https://github.com/mathisschmieder/gqrx]||

||rtl_fm||SDR CLI||Kyle Keen||merged in librtlsdr master||

||SDR#||SDR GUI||Youssef Touil||[http://sdrsharp.com/] and [http://rtlsdr.org/softwarewindows Windows Guide] or [http://rtlsdr.org/softwarelinux Linux Guide]||

||tetra_demod_fft||Trunking RX||osmocom team||[http://cgit.osmocom.org/cgit/osmo-tetra/tree/src/demod/python/osmosdr-tetra_demod_fft.py osmosdr-tetra_demod_fft.py] and the [http://tetra.osmocom.org/trac/wiki/osmo-tetra#Quickexample HOWTO] ||

||gqrx (original)||SDR GUI||Alexandru Csete||[https://github.com/csete/gqrx]||

||airprobe||GSM sniffer||osmocom team et al||[http://git.gnumonks.org/cgi-bin/gitweb.cgi?p=airprobe.git]||

||gr-smartnet (WIP)||Trunking RX||Nick Foster||[http://www.reddit.com/r/RTLSDR/comments/us3yo/rtlsdr_smartnet/][[br]][http://www.reddit.com/r/RTLSDR/comments/vbxl0/attention_grsmartnet_users_or_attempted_users/ Notes from the author]||

||gr-air-modes||ADS-B RX||Nick Foster||[https://www.cgran.org/wiki/gr-air-modes] call with --rtlsdr option||

||Linrad||SDR GUI||Leif Asbrink (SM5BSZ)||[http://www.nitehawk.com/sm5bsz/linuxdsp/hware/rtlsdr/rtlsdr.htm][[br]]DAGC changes were applied to librtlsdr master||

||gr-ais (fork)||AIS RX||Nick Foster[[br]]Antoine Sirinelli[[br]]Christian Gagneraud||[https://github.com/chgans/gr-ais]||

||GNSS-SDR  '''(NEW)'''||GPS RX (Realtime!)||Centre Tecnològic de[[br]]Telecomunicacions de Catalunya||[http://www.gnss-sdr.org/documentation/gnss-sdr-operation-realtek-rtl2832u-usb-dongle-dvb-t-receiver Documentation] and [http://www.gnss-sdr.org]||

||LTE-Cell-Scanner '''(NEW)'''||LTE Scanner||James Peroulas||[https://github.com/Evrytania/LTE-Cell-Scanner]||

||Simulink-RTL-SDR '''(NEW)'''||MATLAB/Simulink wrapper||Michael Schwall[[br]]Sebastian Koslowski[[br]]Communication Engineering Lab (CEL)[[br]]Karlsruhe Institute of Technology (KIT)||[http://www.cel.kit.edu/simulink_rtl_sdr.php]||

||gr-scan '''(NEW)'''||Scanner||techmeology||[http://www.techmeology.co.uk/gr-scan/]||

[[br]]

Using our lib? Tell us! Don't? Tell us why! :)

[[br]][[br]][[br]]

[[Image(rtl-sdr-gmr.png)]][[br]]

Multiple GMR-carriers can be seen in a spectrum view with the full 3.2 MHz bandwidth (at 3.2 MS/s).