[time-nuts] FE-.5680A trimming resolution
magnus at rubidium.dyndns.org
Wed Feb 1 23:59:10 UTC 2012
On 01/02/12 15:07, John Ackermann N8UR wrote:
> There've been numerous threads on the Gnuradio mailing list about code
> to receive GPS using the Ettus Research USRP hardware. I don't know
> whether anyone has actually made it work, but it appears that it's been
> the subject of quite a few academic projects.
I bought one of those GNSS samplers, pulled data from the air and
actually managed to have my GPS SDR written in C scan the doppler bins
and code-phases with FFT correlation techniques (with a little help of
FFTW), find a bird and lock the PLL up to it... locked onto the symbols
and started spitting out the sub-code info. I wrote all the code myself
except for the USB application. I also spent some time to start
calculating position and such.
I will have to get one of those Ettus Research devices to be able to do
anything useful thought.
So, it is certainly possible. Takes a few of the software GPS books
alongside the ICD-GPS-200 and traditional GPS books to piece together
the full suite of references, but it didn't take THAT long to get where
More information about the time-nuts