Re: [Discuss-gnuradio] Synchronization issue with multiple USRPs

From:

Khalid Jamil

Subject:

Date:

Tue, 26 Apr 2011 19:36:23 +0300

The GRC file is attached. Here i am showing it scope sink with six
channels.

Khalid.

Date: Sun, 24 Apr 2011 23:36:54 -0700
From: Josh Blum <address@hidden>
To: address@hidden
Subject: Re: [Discuss-gnuradio] Synchronization issue with multiple
USRPs
Message-ID: <address@hidden>
Content-Type: text/plain; charset=ISO-8859-1

Could you post a screen shot of the flow graph or attach the grc file? -Josh

On 04/24/2011 11:10 PM, Khalid Jamil wrote:
> Hi,
>
> I have an eight element circular antenna array and I want to do beamforming
> using eight N210s in receive mode. So, I distributed 10MHz/1PPS reference to
> each N210 to synchronized them and routed the eight GbE ports through a
> switch to the computer. I store data from each channel in one file/channel
> using gnuradio companion. Later I want to do beamforming processing.
>
> Now, when I start receiving the data, there is a fixed phase offset from
> channel to channel. That's OK as long as I know how much is it. The problem
> I am facing is that this phase offset is random each time you start
> acquiring the data. Now how can i know about it to make a correction in the
> array processing. Is there a way to fix it or take care of it in system
> calibration?
>
> Thanks,
>
> Khalid.
>
>
>