osmocom Gnu Radio Blocks

While primarily being developed for the OsmoSDR hardware, this block as well supports:

• ​FunCube Dongle through libgnuradio-fcd
• sysmocom OsmoSDR Devices through ​libosmosdr
• ​Great Scott Gadgets HackRF through ​libhackrf
• ​Ettus USRP Devices through ​Ettus UHD library
• RTL2832U based DVB-T dongles through librtlsdr
• RTL-TCP spectrum server (see librtlsdr project)
• MSi2500 based DVB-T dongles through ​libmirisdr
• gnuradio .cfile input through libgnuradio-blocks

By using the OsmoSDR block you can take advantage of a common software api in your application(s) independent of the underlying radio hardware.

Build process

The Gnu Radio block requires a recent gnuradio (>= v3.7 if building master branch or 3.6.5 when building gr3.6 branch) to be installed.

Before building the block you have to make sure that all the dependencies (see list of supported devices above) you are intend to work with are properly installed. The build system of gr-osmosdr will recognize them and enable specific source/sink components thereafter.

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:

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

If you are building for gnuradio 3.6 series, you have to switch to the gr3.6 branch as follows

git checkout gr3.6

mkdir build
cd build/
cmake ../

Now cmake should print out a summary of enabled/disabled components. You may disable certain components by following guidelines shown by cmake. Make sure the device of your interest is listed here. Check your dependencies and retry otherwise.

-- ######################################################
-- # gr-osmosdr enabled components                         
-- ######################################################
--   * Python support
--   * Osmocom IQ Imbalance Correction
--   * sysmocom OsmoSDR
--   * FunCube Dongle
--   * IQ File Source
--   * Osmocom RTLSDR
--   * RTLSDR TCP Client
--   * Ettus USRP Devices
--   * Osmocom MiriSDR
--   * HackRF Jawbreaker
-- 
-- ######################################################
-- # gr-osmosdr disabled components                        
-- ######################################################
-- 
-- Building for version: 4c101ea4 / 0.0.1git
-- Using install prefix: /usr/local

Now build & install

make
sudo make install
sudo ldconfig

NOTE: The osmocom source/sink blocks will appear under 'Sources' and 'Sinks' categories in GRC menu.

To build the API documentation:

cd build/
cmake ../ -DENABLE_DOXYGEN=1
make -C docs

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.

Device specification

You can specify the source or sink device using a comma separated string of argument=value pairs. The always-up-to-date block documentation with examples is available ​right here.

FCD Source

Argument	Notes
fcd=<device-index>	0-based device identifier

OsmoSDR Source

Argument	Notes
osmosdr=<device-index>	0-based device identifier
buffers=<number-of-buffers>	Default is 32
buflen=<length-of-buffer>	Default is 256kB, must be multiple of 512

RTL-SDR Source

Argument	Notes
rtl=<device-index>	0-based device identifier OR serial number
rtl_xtal=<frequency>	Frequency (Hz) used for the RTL chip, accepts eng notation
tuner_xtal=<frequency>	Frequency (Hz) used for the tuner chip, accepts eng notation
buffers=<number-of-buffers>	Default is 32
buflen=<length-of-buffer>	Default is 256kB, must be multiple of 512
direct_samp=0|1|2	Enable direct sampling mode on the RTL chip. 0: Disable, 1: use I channel, 2: use Q channel
offset_tune=0|1	Enable offset tune mode for E4000 tuners

NOTE: use rtl_eeprom -s to program your own serial number to the device

NOTE: if you don't specify rtl_xtal/tuner_xtal, the underlying driver will use 28.0MHz

RTL-SDR TCP Source

Argument	Notes
rtl_tcp=<hostname>:<port>	hostname defaults to "localhost", port to "1234"
psize=<payload-size>	Default is 16384 bytes
direct_samp=0|1|2	Enable direct sampling mode on the RTL chip 0=Off, 1=I-ADC input enabled, 2=Q-ADC input enabled
offset_tune=0|1	Enable offset tune mode for E4000 tuners

Miri Source

Argument	Notes
miri=<device-index>	0-based device identifier
buffers=<number-of-buffers>	Default is 32

NOTE: if you don't specify rtl_xtal/tuner_xtal, the underlying driver will use 28.0MHz

UHD Source / Sink

Argument	Notes
uhd	Use this argument without a value
nchan=<channel-count>	For multichannel USRP configurations use the subdev parameter to specify stream mapping
subdev=<subdev-spec>	Examples: "A:0", "B:0", "A:0 B:0" when nchan=2. Refer original ettus documentation on this
lo_offset=<frequency>	Offset frequency in Hz, must be within daughterboard bandwidth. Accepts eng notation

Additional argument/value pairs will be passed to the underlying driver, for more information see ​specifying the subdevice and ​common device identifiers in the Ettus documentation.

HackRF Source / Sink

Argument	Notes
hackrf	Use this argument without a value
buffers=<number-of-buffers>	Default is 32

Only the first device found may be used at the moment because of libhackrf limitation.

Transmit support has been verified by using the crc-mmbTools DAB sdr transmitter.

IQ File Source

Argument	Notes
file=<path-to-file-name>
freq=<frequency>	Center frequency in Hz, accepts eng notation
rate=<sampling-rate>	Mandatory, in samples/s, accepts eng notation
repeat=true|false	Default is true
throttle=true|false	Throttle flow of samples, default is true

Included Apps

Spectrum Browser

usage examples:

osmocom_fft -a rtl=0 -v -f 100e6 -s 2.4e6 -g 15
osmocom_fft -a hackrf -v
osmocom_fft -a uhd -v

Signal generator

usage examples:

osmocom_siggen -a hackrf -f 100e6 --sine
osmocom_siggen -a hackrf -f 100e6 --sweep -x 2M -y 1 -c34
osmocom_siggen_nogui -a hackrf -f 100e6 --sweep -x 2e6 -y 10 -v
osmocom_siggen_nogui -a uhd,subdev=A:0 -f 100e6 --sweep -x 2e6 -y 10 -s 4e6 -v

Spectrum sensing

TODO: document

Known Apps

The following 3rd party applications are successfully using gr-osmosdr:

Name	Type	Author	URL
gr-pocsag	GRC Flowgraph	Marcus Leech	​https://www.cgran.org/browser/projects/gr-pocsag/trunk
multimode RX	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
Wireless Temp. Sensor RX	Gnuradio App	Kevin Mehall	​https://github.com/kevinmehall/rtlsdr-433m-sensor
gqrx	SDR GUI	Alexandru Csete	​https://github.com/csete/gqrx
tetra_demod_fft	Trunking RX	osmocom team	​osmosdr-tetra_demod_fft.py and the ​HOWTO
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/ ​Notes from the author
gr-air-modes	ADS-B RX	Nick Foster	​https://www.cgran.org/wiki/gr-air-modes call with --rtlsdr option
gr-ais (fork)	AIS RX	Nick Foster Antoine Sirinelli Christian Gagneraud	​https://github.com/chgans/gr-ais
GNSS-SDR	GPS RX (Realtime!)	Centre Tecnològic de Telecomunicacions de Catalunya	​Documentation and ​http://www.gnss-sdr.org
gr-scan	Scanner	techmeology	​http://www.techmeology.co.uk/gr-scan/
pocsag-mrt	Multichannel Realtime Decoder	iZsh	​https://github.com/iZsh/pocsag-mrt
osmo-gmr-rtl	GMR1 RX	Dimitri Stolnikov	​http://gmr.osmocom.org/trac/wiki/GettingStarted#RTLSDRdongles
simple_ra (NEW)	Radio Astronomy App	Marcus Leech	​https://cgran.org/wiki/simple_ra
FS20_decode (NEW)	FS20 Decoder	Thomas Frisch	​https://github.com/eT0M/rtl_sdr_FS20_decoder
OpenLTE (NEW)	LTE Toolkit	Ben Wojtowicz	​http://sourceforge.net/p/openlte/home/Home/

Credits

gr-osmosdr is developed by Dimitri Stolnikov with contributions from Hoernchen and Steve Markgraf.