Re: [Discuss-gnuradio] build from source fails - Kubuntu 16.04 / master
Hi, > Most likely you have an old uhd or uhd devel headers installed somewhere. Uh, so I will need to search for this. But I never did anything else but git pull, make, make install with uhd :) Also the whole system is not too old...but who knows?! > Cheers, > >Sylvain Thanks a lot for the hint :) Ralph. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Control Port Thrift Issues
t;>>Does my FG not measure what I claim to be >>>>> wishing to >>>>> measure? >>>>> >>>>>If it does measure it correctly, why do my >>>>> expectations >>>>> of options A and B leading to a different (though >>>>> improved) situation >>>>> not eventuate? >>>>> >>>>> >>>>>Kind Regards, >>>>> >>>>> >>>>> John >>>>> >>>>> ___ >>>>> Discuss-gnuradio mailing list >>>>> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> >>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>>> <https://lists.gnu.org/mailman/listinfo/discuss-gnuradio> >>>>> >>>>> -- >>>>> Very Respectfully, >>>>> Dan CaJacob >>>>> >>>>> >>>>> ___ >>>>> Discuss-gnuradio mailing list >>>>> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> >>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>>> <https://lists.gnu.org/mailman/listinfo/discuss-gnuradio> >>>> >>>> >>>> >>>> ___ >>>> Discuss-gnuradio mailing list >>>> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> >>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>> <https://lists.gnu.org/mailman/listinfo/discuss-gnuradio> >>> >>> >>> ___ >>> Discuss-gnuradio mailing list >>> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> >>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>> <https://lists.gnu.org/mailman/listinfo/discuss-gnuradio> >>> >> >> ___ >> Discuss-gnuradio mailing list >> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> >> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- next part -- An HTML attachment was scrubbed... URL: <http://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20170913/99e78475/attachment.html> -- Message: 5 Date: Wed, 13 Sep 2017 23:20:45 +0200 From: H?kon V?gsether To: GNURadio Discussion List Subject: [Discuss-gnuradio] [SOCIS '17] GRC C++ Output: Week 7 Message-ID: Content-Type: text/plain; charset="utf-8" Hi all, I was on holiday the previous week, but I have created a poster which I have included in my latest blog post. You can read more at: https://grccpp.wordpress.com/ Best regards, H?kon V?gsether -- next part -- An HTML attachment was scrubbed... URL: <http://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20170913/e4f0a7b9/attachment.html> -- Message: 6 Date: Thu, 14 Sep 2017 00:08:47 -0700 From: James Wanga To: discuss-gnuradio@gnu.org Subject: [Discuss-gnuradio] Time sinks out of sync after adding and removing noise in simple FSK simulation Message-ID: <6ef42589-cdc9-4b97-b127-32b78e611...@gmail.com> Content-Type: text/plain; charset="utf-8" Hello. I?m quite new to both SDR and Gnuradio an have been learning by exploring naive simulations. I recently decided to simulate an FSK modulation scheme with a constant source, a noice source and 2 time sinks. The first time sink is pre-modulation and the second is post-modulation. When I first start the simulation, both time sinks display the same waveform as expected. When I add a strong noise signal in real time via a GUI entry the post-modulation time sink displays a randomly changing waveform again, as expected. However, when I reduce the noise source to 0, the post-modulated sink stabilizes to match the pre-modulated sink except that it is translated arbitrarily to the left or right. this causes an arbitrary byte to be spit out when the bits are repacked. I?m sure I?m missing some basic concept that will make this make sense. can someone point me to my oversight? Thank you. I?ve attached screenshots of my flow graph and the sink outputs. -- next part -- An HTML attachment was scrubbed... URL: <http://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20170914/5101167b/attachment.html> -- next part -- A non-text attachment was scrubbed... Name: Screen Shot 2017-09-13 at 11.39.16 PM.png Type: image/png Size: 371830 bytes Desc: not available URL: <http://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20170914/5101167b/attachment.png> -- next part -- A non-text attachment was scrubbed... Name: Screen Shot 2017-09-13 at 11.37.36 PM.png Type: image/png Size: 396655 bytes Desc: not available URL: <http://lists.gnu.org/archive/html/discuss-gnuradio/attachments/20170914/5101167b/attachment-0001.png> -- next part -- A non-text attachment was scrubbed... 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Re: [Discuss-gnuradio] Time sinks out of sync after adding and removing noise in simple FSK simulation
On Thu, Sep 14, 2017 at 12:08 AM, James Wanga wrote: > I recently decided to simulate an FSK modulation scheme with a constant > source, a noice source and 2 time sinks. The first time sink is > pre-modulation and the second is post-modulation. When I first start the > simulation, both time sinks display the same waveform as expected. When I > add a strong noise signal in real time via a GUI entry the post-modulation > time sink displays a randomly changing waveform again, as expected. > However, when I reduce the noise source to 0, the post-modulated sink > stabilizes to match the pre-modulated sink except that it is translated > arbitrarily to the left or right. this causes an arbitrary byte to be spit > out when the bits are repacked. > This is not an effect of your simulation but an actual problem in digital communication. When you introduce noise, the GFSK Demod loses track of the actual symbol timing and so its estimate drifts freely. When you remove the noise, it locks on again starting at who-knows-what symbol out of your 8-symbol groups. The same problem would occur in a real receiver which does not share a clock with the transmitter, because you start in the no-information state. If you want to recover properly aligned bytes (or packets, even) you need a way to detect where one begins. This is usually done with a known sequence of symbols at the beginning of a transmission. Unfortunately, I don't have experience with the digital blocks available in GNU Radio so I cannot tell you how to construct a working example. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Control Port Thrift Issues
gards, > >>> > >>> John > >>> > >>> > >>> > >>> On 11/09/17 01:03, Marcus D. Leech wrote: > >>>> On 09/10/2017 08:58 PM, Dan CaJacob wrote: > >>>>> > >>>>> I could be wrong, but I thought the SBX was one of the few > >>>>> daughter cards that starts with s known phase offset? > >>>>> > >>>> Only if you ask it to do so, and only if it's sharing clock > >>>> with its buddies... > >>>> > >>>>> > >>>>> On Sun, Sep 10, 2017, 2:49 PM Fulcrum Associates > >>>>> mailto:sla1nte2...@gmail.com>> wrote: > >>>>> > >>>>> Dear All, > >>>>> > >>>>> I have a couple of USRPs connected, through > >>>>> a strong > >>>>> attenuator to a signal generator (NWT4001). While the > >>>>> units have a MIMO > >>>>> option, I don't have that cable. (Option A) When I run the > >>>>> GRC as > >>>>> attached, I see too good a result to the extent that the > >>>>> differential > >>>>> Phi seems to range over +/- 5 degrees. > >>>>> > >>>>> > >>>>> What I had hoped to prove to myself that two > >>>>> N200 with SBX > >>>>> would have a varying offset without MIMO cable, then I > >>>>> would connect the > >>>>> MIMO cable and move the USRPs into a multi-unit and enable > >>>>> GPSD O/B on > >>>>> the unit which has the feature and MIMO for one without > >>>>> (Option B) and > >>>>> that the phase differential would improve noticeably and > >>>>> be a variable > >>>>> constant, but it didn't. > >>>>> > >>>>> > >>>>>If it had, but there still was a fixed > >>>>> phase offset which > >>>>> varied each time it was setup (which is what I would > >>>>> expect under B) > >>>>> then I would hand-code the SBX stream initialisation code > >>>>> to remove the > >>>>> offset. > >>>>> > >>>>> > >>>>>Does my FG not measure what I claim to be > >>>>> wishing to > >>>>> measure? > >>>>> > >>>>>If it does measure it correctly, why do my > >>>>> expectations > >>>>> of options A and B leading to a different (though > >>>>> improved) situation > >>>>> not eventuate? > >>>>> > >>>>> > >>>>>Kind Regards, > >>>>> > >>>>> > >>>>> John > >>>>> > >>>>> ___ > >>>>> Discuss-gnuradio mailing list > >>>>> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> > >>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > >>>>> <https://lists.gnu.org/mailman/listinfo/discuss-gnuradio> > >>>>> > >>>>> -- > >>>>> Very Respectfully, > >>>>> Dan CaJacob > >>>>> > >>>>> > >>>>> ___ > >>>>> Discuss-gnuradio mailing list > >>>>> Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> > >>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > >&g
[Discuss-gnuradio] Tonight: Cyberspectrum Software Defined Radio Meetup (San Diego, Thu Sept 14th, 6:30PM PT)
Dear all, Announcing the the 22nd #cyberspectrum special meetup tonight, during this exciting week of #GRCon17, from 6:30 PM in San Diego at Qualcomm. For those that wish to try car pooling, please meet at the GRCon hotel lobby at 6 PM. For those unable to attend the event in person, you can live stream it here: https://www.youtube.com/watch?v=u1RA8eScOIs There's also IRC: #cyberspectrum on Freenode. Full details, including the speaker lineup/topics, are here: https://www.meetup.com/Cyberspectrum/events/243307509/ Don't forget all our videos are here: https://www.youtube.com/ playlist?list=PLPmwwVknVIiXGzKhtimTMjhcyppeRRsnE ...and materials here: http://www.meetup.com/Cyberspectrum/about/ For updates before, and photos during the event: https://twitter.com/spe nchdotnet Please support Cyberspectrum by submitting a talk, requesting a topic/presenters, or spreading the word about us! If you would like to learn more about setting one up, please get in touch. (Anyone on the US East Coast?) If you're not familiar with Cyberspectrum: "The Bay Area SDR Meetup will serve as a forum to exchange knowledge and ideas related to Software Defined Radio (the software and hardware), and generally aim to get people excited about all the applications that can be realised with the technology. At each meetup, attendees will have the opportunity to present their work/ideas to the group. Engineers, enthusiasts, hobbyists and people of all experience levels are welcome, no matter what your software/hardware background." As always, if you would like to present at a future event about a project you're working on, or something interesting you've discovered, please get in touch! Stay tuned and hope to see you there, Balint ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Time sinks out of sync after adding and removing noise in simple FSK simulation
That's really helps me understand what's happening, thank you. I'm curious if this can be solved by sending packets instead of raw bytes. Is it correct to assume that sequence detection is one of the responsibilities of a packet decoder? I'm also curious if I there is any advantage to using a clock recovery block and binary slicer instead of the monolithic GFSK demod block? Stated another way. Is the GFSK demod block just a quadrature demod, clock recovery, and binary slicer rolled into one? Another thought is, once you loose symbol timing, do I need to then dynamically tweak the clock recovery settings (like mu) in order to realign? James Wanga > On Sep 14, 2017, at 7:20 AM, Kevin Reid wrote: > >> On Thu, Sep 14, 2017 at 12:08 AM, James Wanga wrote: >> I recently decided to simulate an FSK modulation scheme with a constant >> source, a noice source and 2 time sinks. The first time sink is >> pre-modulation and the second is post-modulation. When I first start the >> simulation, both time sinks display the same waveform as expected. When I >> add a strong noise signal in real time via a GUI entry the post-modulation >> time sink displays a randomly changing waveform again, as expected. However, >> when I reduce the noise source to 0, the post-modulated sink stabilizes to >> match the pre-modulated sink except that it is translated arbitrarily to the >> left or right. this causes an arbitrary byte to be spit out when the bits >> are repacked. > > This is not an effect of your simulation but an actual problem in digital > communication. > > When you introduce noise, the GFSK Demod loses track of the actual symbol > timing and so its estimate drifts freely. When you remove the noise, it locks > on again starting at who-knows-what symbol out of your 8-symbol groups. The > same problem would occur in a real receiver which does not share a clock with > the transmitter, because you start in the no-information state. > > If you want to recover properly aligned bytes (or packets, even) you need a > way to detect where one begins. This is usually done with a known sequence of > symbols at the beginning of a transmission. Unfortunately, I don't have > experience with the digital blocks available in GNU Radio so I cannot tell > you how to construct a working example. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
