[ Implementing a Phase Shift block]

GNU Radio
1

Hi all,

I’m working on synchronising two USRPs (connected via a MIMO) and have
calibrated the time-offset which occurs between them for a given set of
signal generator’s frequency, USRPs frequency and the sampling rate.

My next step is to do a phase-compensation for one of the USRPs so that
both are aligned in the time-domain. I read from
thishttp://www.ettus.com/content/files/kb/mimo_and_sync_with_usrp.pdfdocument
that for Phase-shifting, we need to use MRC algorithm or Periodic
Calibration. Also I saw that a “Phase Shift” block has been used in that
document which I guess was developed by the author who wrote it, as I
could
not find it in the GRC.

I’m willing to develop one such simple phase-shift block. Can anyone
suggest me how to approach in implementing it i.e in terms of any
algorithm’s reference that you can suggest to achieve this purpose?

Note: I want my Phase-Shift block to work in real time i.e it should be
able to adjust the phase-offset of one of the signals so that that
signal
gets aligned with the other in the time-domain.

Thanks and Regards,

2

On 01/11/2013 02:30 AM, Ashish R. wrote:

document that for Phase-shifting, we need to use MRC algorithm or
signal gets aligned with the other in the time-domain.

Thanks and Regards,

–

The attached demonstrates phase-shifting using a simple complex multiply
block.

If you want to do coarser phase shifts (large multiples of 180deg), you
can use a delay block.