Daniele,

I have worked on this problem for a specific case as well.  I have a
document with source code and a short description of what's happening that
can be found here (
https://www.dropbox.com/s/bcma7fqa7ip2own/unwrap_example.txt).

Michael


On Mon, Jun 16, 2014 at 10:05 AM, Daniele Nicolodi <dani...@grinta.net>
wrote:

> Hello Matt,
>
> thank for your answer. I'm aware of the problem and in my application I
> can keep phase bounded, but not bounded to (-pi, +pi]  therefore I need
> unwrapping to make sense of my modulation data.
>
> If such feature does not exist in GNU radio, I hope it is not too hard
> to code it myself.
>
> Thanks. Cheers,
> Daniele
>
>
> On 16/06/2014 15:44, Matt Ettus wrote:
> >
> > Daniele,
> >
> > The problem with phase unwrapping is that it is unbounded, and will tend
> > to infinity.  Once it gets very big, when you try to add a small number
> > to a very big number, floating point loses precision.  Eventually,
> > adding small to extremely big returns the big number unchanged.  This
> > isn't that useful.
> >
> > Matt
> >
> >
> >
> > On Mon, Jun 16, 2014 at 2:40 PM, Daniele Nicolodi <dani...@grinta.net
> > <mailto:dani...@grinta.net>> wrote:
> >
> >     Hello,
> >
> >     I just started to work with GNU radio for my very basic needs, so
> please
> >     excuse my naive questions and probably my inappropriate use of the
> >     jargon.
> >
> >     My first trivial application of GNU radio is to simply measure the
> phase
> >     of a phase modulated signal with an Ettus Research USRP N210 and a
> LFRX
> >     daughter-board.
> >
> >     Everything works as expected, but I haven't found a way to do phase
> >     unwrapping (removing the 2pi ambiguity in the phase obtained from the
> >     arctan function looking at discontinuities in the phase data). Is
> this
> >     functionality offered somewhere, and I missed it, or should I look
> into
> >     implementing it myself?
> >
> >     Thanks. Cheers,
> >     Daniele
> >
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> >
> >
>
>
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