In https://www.youtube.com/watch?v=B_fs9fWPTWw I discuss time of flight
measurement referenced to a local loopback channel (B210 for coherent
dual input receiver) to get rid of the data transfer and general purpose
computation time and only consider the communication delay. The
correlation phase
At https://github.com/jmfriedt/active_radar/ you will find the solution
I have been using for Synthetic Aperture RADAR using GNU Radio. In this
application I wish to collect coherent measurements from both reference
(transmitted pattern) and surveillance (reflected signal) channels when
Dear GNU Radio community,
the 2023 edition of the European GNU Radio Days will be held in
France, hosted by the SYRTE laboratory of the Paris Observatory,
March 29 & 30, 2023.
The call for participation is hosted at
https://gnuradio-eu-23.sciencesconf.org
with some preliminary program by
I hope I am not stating the obvious ... but time is only defined at the
ADC sampling time, everything afterward is asynchronous and indexed
with sample number.
So you have sampled the I+jQ stream x(n), n\in\mathbb{N} at sampling
rate fs, and now want to FFT every 40 ms. The number of samples in
Salut Maxime,
a lot of arguments seem to have changed with UHD4. In the
UHD: USRP Source, go to RF Options and for each board define
Ch i: Antenna
manually, replacing the TX/RX tab entry with your own.
I use "A" setting.
Probably your Subdev Spec that might have been defined with UHD3
is no
> I am wondering if it is possible to reliably make another gnuradio
> instance on a low powered computer (like a intel minipc or raspberry
> pi) to interface with the SDR and be connected to the high end cpu
> laptop via a lan cable. This would allow the laptop to be placed far
> away easing
GNU Radio 3.9 is now available for embedded boards (including Raspberry
Pis) in the BR2_EXTERNAL repository at
https://github.com/oscimp/oscimp_br2_external
and has been tested (on Raspberry Pi 4) with the 3.9 port of gr-acars
and gr-rpitx as will be presented at FOSDEM. Of course further testing
If it can be of any help, we discussed generating a GPS-aligned 1-PPS
in http://jmfriedt.free.fr/ifcs2021.pdf and the oral presentation at
http://jmfriedt.free.fr/ifcs2021_presentation_jmfriedt.mp4 prepared
for the International Frequency Control Symposium (IFCS).
What we realized when working on
o? That’s how I control most of my
> flowgraphs when i need to automate parameter control, for example on
> a loose timer. I think the internal Python module and snippets are
> more compact though.
>
>
>
> > On Aug 11, 2021, at 12:40, jmfriedt
> > wrote:
> >
I think I have been trying to address this topic in
https://www.youtube.com/watch?v=M8dqgqO4TuI
with complementing 0MQ streaming (target to host) with a TCP-server
thread running next to the GNU Radio Python flowgraph, accepting
commands (host to target) to tune flowchart parameters.
Best, JM
--
Dear GNU Radio enthusiasts,
the European GNU Radio Days will start in two days: those who wish to
attend can connect to the video streams since the whole conference is
held virtually.
The program is now final and a few schedules have been subject to minor
adjustements: please check
Dear GNU Radio enthusiasts,
the program of the European GNU Radio Days is being finalized and is now
published at https://gnuradio-eu-21.sciencesconf.org/program.
Please expect a few minor adjustements as videos are being uploaded but
the coarse schedule is completed and available. The oral
For what it is worth, slide 10 of
https://archive.fosdem.org/2020/schedule/event/fsr_software_defined_radio_based_scientific_instrumentation/attachments/slides/3895/export/events/attachments/fsr_software_defined_radio_based_scientific_instrumentation/slides/3895/fosdem2020_instrumentation.pdf
Dear GNU Radio enthusiasts,
as part of the virtual event European GNU Radio Days to be held June
24--26, 2021 as a joint meeting with the Software Defined Radio Academy
for the Saturday session, our generous sponsor NI is donating two
B205mini. A challenge has been set to select the winners
gt; >
> > On Mon, May 17, 2021 at 11:07 AM jmfriedt
> > wrote:
> >
> >> I am trying to get an accurate timing of a given sample (1-PPS
> >> transition). To do so, a marker is injected in the AD9831
> >> datastream in the B210 FP
I am trying to get an accurate timing of a given sample (1-PPS
transition). To do so, a marker is injected in the AD9831 datastream in
the B210 FPGA. When this tag is detected in the UHD source block, a tag
is created in the stream:
for (item=0;item PPS_tag;
get_tags_in_window(PPS_tag,0,
head is your friend. See attached.
JM
--
JM Friedt, FEMTO-ST Time & Frequency, 26 rue de l'Epitaphe, 25000
Besancon, France
> May 8, 2021 12:58 AM, "Muhammed Sefa KOÇAKOĞLU"
> (mailto:msefakocako...@gmail.com?to=%22Muhammed%20Sefa%20KO%C3%87AKO%C4%9ELU%22%20)>
> wrote: Hi Everyone, I'm
I wanted to demonstrate quantization noise (V_q^12/12/fs noise floor)
with GNU Radio and somehow my demonstration is failing. I am trying
http://jmfriedt.org/untitled.png (or http://jmfriedt.org/untitled.grc)
following the chart of the Quantizer. Somehow I had already noticed
that the Qt Freq Sync
I am characterizing a weak (-80..-60 dBm) signal next (5 MHz away) to a
strong (-30..-40 dBm) carrier interfering with my measurement. I am
looking at power and phase (these are CW signals), and hit the issue
that the interfering carrier affects the sideband power measurement.
To demonstrate the
Thank you for your reply which helped me find a (temporary at least)
solution to my problem: indeed you reminded me that we had been
streaming data from GNU Radio to a MS-Windows computer running ZeroMQ
on its GNU Radio flowgraph and that was working well last
december/january. So downgrading to
> Radio as you need; so, no GRC, no gr-qtgui, hence no GTK, QT, …). I'd
> expect that to easily fit in 4 GB.
we have GNU/Linux + python + GNU Radio in less than 32 MB on the PlutoSDR :)
https://github.com/oscimp/PlutoSDR
JM
--
JM Friedt, FEMTO-ST Time & Frequency/SENSeOR, 26 rue de l'Epitaphe,
> All in all, this is pretty ambitious, but exciting!
> How will you tackle the OFDM signal recovery? I think your reference
> [2] is really much to be completely done in one GSoC, so it would be
> totally OK to say you just picked a reduced approach. Still, if you
> want to do that in all its
after a few more experiments with synthetic signals, I figured out that
the Constellation Decoder output is already the set of bit pairs
expected from the QPSK constellation, not the families themselves. So
as expecter -1-j->00, -1+j->01, 1+j->11 and 1-j->10, it all makes
sense with an output rate
I am investigating Meteor M2 decoding. So far I had tackled BPSK
decoding (RDS, GPS) and it is the first time I analyze QPSK signals.
Based on github.com/otti-soft/meteor-m2-lrpt.git, decoding works
fantastically well, but I don't understand why. Costas and MM Clock
recovery are understood, but it
I am also unable to understand what you aim (or problem) is but if it can be of
any use to you, a small movie of 24 hour of GRAVES radar recording is available
at
http://jmfriedt.free.fr/1707_graves_36h.ogg
Horizontal axis is Doppler shift in Hz (df=2*v/c*143.05 MHz, or a velocity of
750 km/h
> The I/Q plot show complex cross-correlation between two noise signals at
> 100 MHz center frequency (2.4 MHz bandwidth noise). The phase of the signal
> can be converted into time and Allan deviation, but I never did. I was just
> happy to see a straight line.
I continued the measurement this
I am tackling again the coherence issue with multi-RTL dongles for
interferometric measurements.
I have two R820T2 based DVB-T dongles connected to the same USB bus (USB hub)
and am feeding
both dongles with a high quality 100-MHz source (-34 dBm output of a
Rohde SML03 synthesizer,
30 dB gain
as a followup to my own post, some simulation with a smaller FFT size
and synthetic data (as opposed to records from the sound card) do yield
the expected behavior of an FFT analyzer used in cross-correlation
mode: jmfriedt.sequanux.org/test_vector.grc generates a
cross-correlation peak every N
I am trying to understand how to use the output of FFT vectors for computation,
rather than just displaying spectra (FFT Sink). I have assembled a pseudo-random
generators (linear feedback shift registers) which output two identical
pseudo-random
sequences (PRN) when clocked by the sound card
As briefly mentioned at FOSDEM, I have been investigating RDS since last
christmas, trying to
tackle each issue step by step from LO synchronization for BPSK demodulation,
bit decoding,
sentence synchronization, station name and free text extraction, error
correcting code implementation
and
anwering my own question ... just found the answer at
http://www.ece.uvic.ca/~elec350/grc_doc/ar01s05s04.html
that the number of outputs defines the number of input channels (I mistakenly
thought they would be duplicates of the same stream).
JM
> Am I missing an option of the audio source block
Am I missing an option of the audio source block of gnuradio-companion for using
both channels of the stereo microphone input of my sound card ? I'd like to
time-stamp,
using a GPS 1PPS signal, samples recorded from the sound card and use for that
purpose
the second channel of the microphone
My apologies for such a trivial bug report, but has anyone experienced issues
with gr-osmosdr
"lately" (not sure when the problem started) about "PLL not locked" and data
flow rate mismatch
in gnuradio data flows ?
I have a couple dozen RTL2832U based dongles used for various SDR activities
GPS data records and processing scripts for GNU/Octave are available at
http://jmfriedt.free.fr/efts_archive.tar.gz. The tutorial I presented on this
topic during the EFTS seminar is summarized at
http://jmfriedt.free.fr/sdr_gps_eng.pdf
JM
You may try this GPS signal simulator to generate IQ
As briefly mentioned on the #gnuradio IRC mailing list, I am facing an issue
with tuning a R820T
channel
[...]
I have completed the following experiment:
* a frequency synthesizer (Rohde
I am facing an issue with one of my decoding blocks in which I call
manually FFTW3 (ie *not* going through the gnuradio-fftw3
implementation since I have not (yet) understood how it operates). If I
call a processing chain with a single appearance of my processing
block, all goes fine. If I add a
I am completing a summary of this summer's experiments including
* decoding weather satellite and the opportunity to introduce
channelized decoding (Frequency Xlating FIR Filter)
* since satellites are not often visible at my latitude, application
to POCSAG which is easier to grab, and most
I am not aware of the details of the GPSDO implementation but your sources must
be phase locked, not only synchronized through the GPS signal. The GPS control
loop
on the LO only has a finite bandwidth above which each oscillator is free to
drift
at will. Under such conditions, the interference
I wish to inform the GNURadio community on some of the latest results on the
use of the Xilinx Zynq platform
for real time radiofrequency signal processing aimed at making the best use of
the PS/PL architecture.
Let me emphasize that although I am writing this email, all the technical work
has
I am facing a funny issue: I want to use the sound card for analyzing the
spectral response
of a quartz tuning fork at 32768 Hz. I just happened to discover that my laptop
(Panasonic CF-19)
has a sound card able to sample a signal at 192 kHz. I checked with audacity
(Generate - Tone at
32768 Hz
in the system.
Have you tried using the explicit device name (aplay -L) of your
physical device in the audio sink?
Greetings,
Marcus
On 25.06.2014 10:40, jmfriedt wrote:
I am facing a funny issue: I want to use the sound card for analyzing the
spectral response
of a quartz tuning fork
most enthusiastic about this development: I was disappointed not to get the
current
http://www.gnss-sdr.org/documentation/gnss-sdr-operation-realtek-rtl2832u-usb-dongle-dvb-t-receiver
running on my dongle and am really looking forward to some demo on this topic.
JM
Congratulations for the
I am still trying to receive NOAA APT signals using the RTL-SDR DVB dongle.
What I did
so far:
1/ using a wideband discone antenna, I receive the NOAA APT characteristic
signal during passes
on a AOR3000 scanner. I know the NFM mode of the AOR3000 is too narrow for full
decoding of the
image
Is anyone planning on attending the OHM2013 conference
(https://ohm2013.org/site/) in the
nederlands this summer ? I'd like to submit a talk about GNURadio/rtl-sdr and
signal processing
prototyping using this tool/sound card (oriented towards digital mode reception
and time frequency
For what it is worth, some might (or might not) be interested in the
tutorial document I wrote concerning the implementation of some decoding blocs
for GNURadio, from signal processing prototyping using GNU/Octave on recorded
signals
to the actual bloc http://jmfriedt.free.fr/en_sdr.pdf
For the
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