Linking PRIMO with gps-sdr

Hello,

just finished adapting the open-source project www.gps-sdr.com to use PRIMO. On our Ubuntu Karmic 32bit laptop runs nicely but still uses a lot of resources (especially the GUI). The effect is nevertheless outstanding!

Figure 1: The gps-sdr GUI running with PRIMO (PVT window).

Figure 1: The gps-sdr GUI running with PRIMO (alm. and eph. window).

I really have to congratulate with Gregory Heckler and his colleagues for the fantastic job they have done so far. Every PRIMO user can now also enjoy their open-source receiver.

Thank you guys,
Michele


P.S. On their project website you should be able to find the archive with a preliminary snapshot of the code. Compile and run the GUI with ./gps-gse and the receiver with sudo ./gps-sdr -primo. I had no time to test it with the USRP 'cause we only have tweaked ones in the lab.. just be aware I tuned the scaling in acquisition and correlators.

Galileo E5AltBOC tracking in slow motion

Hello everyone,

not grabbed with our "TUNE" boards (the plot would not be as detailed at 61.44Msps) but with our next one I did not write about yet (samples at about 440Msps), here is a basic E5AltBOC pilot signal tracking:

Figure 1: Galileo PRN02 E5AltBOC tracking. Spirent GSS8000 simulator, static scenario, GPS L1, L2, L5, Galileo E1, E5a/b, E6 all in view.



Figure 1: GIOVE-B E5AltBOC tracking. Clear sky conditions, Novatel GPS704-X antenna, static scenario in Nottingham, May the 6th 2010, 00:05 GMT.

These animations are obtained using octave and ffmpeg... at 40x slower motion :)

More to come soon,
Michele

Opening the door to new signals

Well,

I don't manage to keep my promise of updating regularly this blog (blush). Anyway, I am improving little by little so another pretty stable thing is a board which I use to capture the new civil signals from GPS, Glonass, Galileo, Compass. I might refer to it as "TUNE".

Figure 1: Six single channel TUNE boards.

With a much wider bandwith than PRIMO, these boards can capture through USB a continuous endless stream of E5AltBOC signal with 1 bit quantisation (122.88Mbps). Two can also be connected together to have some sort of a dual-frequency sampler.

At the moment, the GUI to configure everything (tuner, clock distribution, ADC) is a little "complicated":

Figure 2: The TUNE configuration GUI.

...so it's my next part-time job to make it little more user friendly.
Some results of acquisitions and tracking of "famous" signals will follow shortly.


Regards everyone and thanks for all the comments had so far,
Michele

Still alive and working hard

Hi,

despite not writing anything in here, I have been working on a new version of the dongle and on many other things.

First, I'm now in hardware design: look at the new signal samplers, my personal joy and pride :)

Fig.1: Primo USB dongles: very flexible GNSS data samplers.

These have the same functionality of the old CPLD version, but are more slick and robust. Eheh!

Second, I'm playing with a new platform:

Fig.2: The Gumstix Overo Earth runs our software GNSS receiver.

Above is one of our dongles connected to a Gumstix OVERO earth carrier board. Not only the OMAP3503 can reliably record the raw GNSS stream, but it is also capable of processing 16 GPS -or Galileo BOC(1,1)- channels in real-time, continuously!
To do that, quite some assembly code had to be written (especially for the FFTs!). The NEON core within the Cortex-A8 is a wonderful machine, and the learning curve with gcc is very acceptable. I won't give more details of how we did it, just want to share -again- my joy and pride :)

To finish, this time I HAVE TO thank all my colleagues-friends working hard with me at NSL, and the opensource community of the Beagleboard and the BeagleSDR project.

Cheers!
Mic

P.S.: Next post is coming soooon...