Re: [Discuss-gnuradio] Interest in beamforming and GNSS receivers

[Pavol Ďuriš]

Hi all,

I have an interest in radioastronomy. I plan to make simple beamforming phase array (primary with 4 and later with 8 antennas) with USRP (later with 2) and GNU Radio. I am inspired by LOFAR radiotelescope.
Now I collect all available information about using GNU Radio and USRP for it.

Martin, could you send more information about your solution, project (url etc.) ?

Thanks,
Pavol

PS: I haven't USRP yet. However, I am buying my first USRP, right now :)

Martin Dvh wrote:

Carles Fernandez wrote:
  

How well are they synchronized?
    

They run off the same 64 MHz clock, so are synchronised.
I have even used two connected USRPs running of the same clock (one is master and exports its clock to the slave USRP)
(You use an additional flatcable between the USRPS and an align software block in gnuradio which aligns the samples)
This gives you 8 ADCs. This means 8 real channels or 4 complex channels.

I used this setup for a phase array with 4 DBSRX daughterboards.
(DBSX daughterboards use complex sampling so they need two ADCs)
DBSRX boards also support the GPS frequencies and are a lot cheaper, so you might want to consider them.
But they are receive only.

You can even go higher and connect 4, 8 or 16 USRPS.