On Mon, 2008-11-10 at 20:14 +0100, Bruhtesfa Ebrahim wrote: > Hi Johnathan, > > Thank you so much for the advise that you gave me ! ! ! > Could you also look at the following description and give me your > comment.? - Thanks > > Ya! I am looking to detect human motion at a distance of minimum 1 > meter and maximum 10 meter. > I have one USRP and two XCVR2450 Trancievers(operating freq. 2.45GHz), > which I will be using one of them as transmitter and the > other as reciever. So, I have two possible ways of implemetation. > > 1) As pulse doppler radar = here to get a minimum distance of 1 > meter, the usrp should transmit a pulse of width 5 nanosec, then > should stop and the reciever should start to recieve, then to measure > a velocity as high as 3m/sec, I can use PRF of 100. Here the problem > is as you said the USRP can not generate such a short pulse of 5 > nanosec, plus it can not switch between transmitter and reciever so > fast. > > 2) As CW radar = here my idea is to transmit a CW from one shell > script and recieve the reflected data at the same time in another > shell script. Here the problem is the isolation between the transmit > and recieve paths. The data I recieve will not be just a reflected > data but also signal from the transmitter. > > This means both of the implementation ways have problem. > So, what do you suggest? Just my 2 cents. I would suggest using sound in stead of radio waves. The lower speed of soundwaves (around 300 m/sec) means the timings go down with a factor 1000000 and you could do very precise short-range radar (actually sonar).
You could still use the USRP. Just use amplifiers and ultrasonic transducers in stead of antenna's. Good luck, Martin > And which one do you recommend me from your previous experience on the > USRP? > > > Also Mr. Lee Pathon, the Author of "GNU based Software Defined > Radar ", I know you worked on such stuff , could you give me some > comment based on your work? - Thanks > > Bruhtesfa > > > > > > On Mon, Nov 10, 2008 at 4:45 PM, Johnathan Corgan > <[EMAIL PROTECTED]> wrote: > On Mon, 2008-11-10 at 16:39 +0100, Bruhtesfa Ebrahim wrote: > > > Is there any tutorial (documentation) that explains in > detail > > gr_radar_mono and other gnu radio packages? > > I look on GNU radio 3.0svn documentation but it has no > details. is > > there any other that has more details? > > > There is a README inside the directory that explains the > command-line > parameters. > > But I'll warn you ahead of time that, based on a prior email > where you > said you were looking at targets 10 meters away, that this > software > won't work for you. > > Without going in to detail, the minimum range is about 200m, > based on > transmitting a long enough chirp and the time it takes to > switch from TX > to RX. > > Just FYI, however, this software was able to image targets 1.5 > km away, > using an RFX2400, a 3W PA, and a horn antenna. > > -Johnathan > > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
