Tilen, gr-radar is probably still a great starting point. I was playing around with it just recently, and will be contributing some fixes to gr-radar in the next few week.
B210 support, I think, is not natively available. I was going to characterize the TX/TX leakage, I'm not entirely sure how well it'll fare for radar applications. In you case, leakage could be drown out your measurements, but maybe it won't. -- M On 02/09/2018 12:48 PM, Tilen Matkovič wrote: > Hi, > > thanks for quick reply! > > I was aware of range resolution equation, apparently I didn't specify > project enough and wasn't really paying attention while reading some > articles :/. > > Goal of my project would be to measure breathing/heartbeat rate of a > human using FMCW radar in GNU radio. I just realized that I do not need > to measure the distance of some object (human chest in my case), but > only the phase variation, which would be much more precise for breathing > monitoring than technique used in gr-radar, with some other limitations. > > I believe that beam antennas would help me, so I will try to use them > also, once I understand theory and get it working in implementation. > > Article and webpage that helped me to understand such monitoring: > Smart Homes that Monitor Breathing and Heart Rate > - http://witrack.csail.mit.edu/vitalradio/content/vitalradio-paper.pdf > <http://witrack.csail.mit.edu/vitalradio/content/vitalradio-paper.pdf> > http://hforsten.com/heartbeat-detection-with-radar.html > <http://hforsten.com/heartbeat-detection-with-radar.html> > > If such implementation for monitoring phase variation already exists in > GNU radio, please point me in right direction :) > > Regards, > Tilen > > 2018-02-08 19:02 GMT+01:00 Sebastian Müller <gse...@gmail.com > <mailto:gse...@gmail.com>>: > > Hi Tilen, > > Am 8. Februar 2018 um 16:31:37, Tilen Matkovič > (matkovic.ti...@gmail.com <mailto:matkovic.ti...@gmail.com>) schrieb: > >> Hello everyone, >> >> I am working on a project where I am using radars to measure >> distance/range from one point to another (with relatively high >> range resolution - range of centimeters or even millimeters). > > Generally I’m not sure if you will achieve this with the B210 > hardware you mention later. Keep in mind the range resolution > equation for radar: > > dr >= c/(2*B) > > For a range resolution of 1 cm you’ll need a signal bandwidth of 15 > GHz [1], while the URSP has a maximum frequency coverage of up to 6 > GHz, which means your center frequency plus half the bandwidth must > be less equal 6 GHz. Common radars, for instance in automotive > applications, work on a center frequency near 100 GHz, allowing much > higher bandwidths! > >> I found the gr-radar (https://github.com/kit-cel/gr-radar/ >> <https://github.com/kit-cel/gr-radar/>) module for GNU radio, >> which already has some implemented radar techniques, the most >> promising for me would be the FMCW radar. But the github >> repository was not updated in years, so I am asking you guys if >> some of you may know some alternatives for GNU radio (googling >> radar gnuradio was not so successful) or maybe anyone has already >> worked with gr-radar. > > I’m not aware of any other projects, but I’ve used gr-radar myself. > It definitely works in the real world, which you can see on Stefan’s > Youtube channel [2]. > >> Now what exactly is my problem - I managed to get the gr-radar - >> FMCW working on one USRP B210 (with TX/RX and RX2 using >> omnidirectional antennas). I was playing around with modifying >> some of the variables but I am still not getting useful range data >> (mostly it is constant, even if moving both of the antennas for a >> few meters or putting some obstacles in between). Modifying the >> samp_rate or sweep_freq, and others (samp_cw, samp_up, samp_down) >> has also not given me useful results. > > The original setup for gr-radar consisted of two USRP N210, > connected with a MIMO cable. It never ran on a B10, though there > were some attempts, that seem to never have been further pursued [3]. > > Also, since you’re using omnidirectional antennas with FMCW, you’ll > detect a lot of static objects in *all* azimuth angles, while > gr-radar was designed for one target only IIRC. So assuming it > theoretically could work on a B210 (please let us know!!), I would > propose to use beam antennas and try to use the dual CW waveform, > which only detects moving objects. > > Let us know about any progress :) >> >> Perhaps I am doing something wrong and not understanding the >> theoretical principles about radars/signal processing or maybe the >> FMCW flowgraph is not implemented correctly? I also have to >> mention here that author (on github) only tested the FMCW >> flowgraph in the simulation (which works ok), but not on the hardware. >> >> Thanks for your help. >> >> Regards, >> Tilen >> _______________________________________________ >> 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> > > >> > > [1] http://www.radartutorial.eu/01.basics/Range%20Resolution.en.html > <http://www.radartutorial.eu/01.basics/Range%20Resolution.en.html> > [2] https://www.youtube.com/channel/UCv7cqqFkkiRFJIGkNEyMu3g > <https://www.youtube.com/channel/UCv7cqqFkkiRFJIGkNEyMu3g> > [3] https://github.com/kit-cel/gr-radar/issues/19 > <https://github.com/kit-cel/gr-radar/issues/19> > > Regards, > > Sebastian Müller > gse...@gmail.com <mailto:gse...@gmail.com> > PGP ID DC2AA3EE > <http://pgp.mit.edu/pks/lookup?op=vindex&search=0x9FFBD55DDC2AA3EE> > > > _______________________________________________ > 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 > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio