On Fri, Nov 25, 2011 at 7:01 AM, Nick Othieno <nickothi...@gmail.com> wrote: > Hi Ryan, > > What did you use for your setup, ie daughterboards, antenna and LNA (if you > do not mind my asking). I have been trying a setup for months that uses a > DBSRX2 and a mighty mouse 2 antenna only, but I have never been able to > acquire the L1 signal. I am wondering where I have gone wrong in the setup.
I've successfully used a DBSRX + active antenna to receive GPS signals before. What software are you using to do the correlation and find the L1 signal? --n > > Nick > > On Fri, Nov 18, 2011 at 9:47 AM, Wolfarth, Ryan <wolfa...@muohio.edu> wrote: >> >> Hi folks, >> >> My group is using USRPs to do the task Kouki described, although our flow >> diagram is a little different. We only use the USRP2 to receive the raw RF >> data which is written to file. This data is processed to the point where we >> decode the navigation bits, but no position is ever found. We're more >> interested in the effects of ionosphere scintillations on GNSS signal >> structure so we don't need to calculate antenna position. >> >> I can recommend two books that have helped me immensely. The Kaplan "blue >> book:" >> >> >> http://www.amazon.com/Understanding-GPS-Principles-Applications-Second/dp/1580538940/ref=sr_1_1?ie=UTF8&qid=1321627222&sr=8-1 >> >> And the Kaplan "blue book:" >> >> http://www.gpstextbook.com/ >> >> I do know of a group that has used a USRP1 to develop a 4 channel L1 >> receiver, but they had to modify the FPGA to do all the real time >> processing. Let me know if you have additional questions! >> >> -Ryan >> >> On Fri, Nov 18, 2011 at 7:56 AM, Brian Padalino <bpadal...@gmail.com> >> wrote: >>> >>> 2011/11/18 山本弘貴 <k.yamamoto.0...@gmail.com>: >>> > Hi, All >>> > I have very trouble >>> > My experiment enviroment isUBUNTU 11.04 , USRP N200, DBSRX2 ,active >>> > antenna and gnuradio >>> > I am worrying about good software GPS receiver is not exist . >>> > I want to receive L1 signal , and want to demodulate that signal >>> > However GPS signal is used Spread spectrum modulation scheme. >>> > I try to creating gnuradio-companion's blocks.(use to Spread spectrum >>> > demodulation blocks) >>> > but that is very difficult so Now I think method is >>> > >>> > GPS L1 signal → USRP N200 → gnuradio-companion(UHD_source→File_sink) >>> > → software decode soft → output(Location data) >>> > >>> > >>> > Eventually I want to Calculate location data, >>> > Please let me know if you're a good this way >>> >>> I recently came across this product listing at Spark Fun: >>> >>> http://www.sparkfun.com/products/10981 >>> >>> Which has a link to a book all about GPS receiving and even comes with >>> MATLAB source code: >>> >>> >>> http://www.amazon.com/Software-Defined-GPS-Galileo-Receiver-Single-Frequency/dp/0817643907 >>> >>> I am sure, with the source, you could adapt it to use the USRP >>> recorded signal, and then possibly port the MATLAB over to either >>> Python (using Josh's signal processing in Python blocks) or straight >>> C++. >>> >>> > I am sorry that My English is not good >>> > >>> > Kouki >>> >>> Good luck - it's definitely not a trivial task, but it sounds extremely >>> fun. >>> >>> Brian >>> >>> _______________________________________________ >>> 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 >> > > > _______________________________________________ > 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
