2 x 1 MISO Transmission with WBX

GNU Radio
1

Hi,

I am trying to transmit simultaneously from two WBX boards each in an
N210. They are connected to each other via a MIMO cable, and then one is
connected to my PC by Ethernet.

They are both synchronized with external PPS and 10MHz from the Ettus
Octoclock system.

I have connected them both to an oscilloscope and there the two inputs
are only sometimes are correlated, and the delay is variable.

Is the flow graph attached the correct way to achieve ‘simultaneous’
transmission? And what sort of offset can I expect?

Thanks,

David

2

Hi All,

I resolved the problem by using a single USRP sink with two mother
boards, as shown in the attached. I now get totally synchronized
transmission from both USRPs - even without any message/tagging blocks
(as suggested by Mike). I inferred this setup from
‘rx_multi_samples.cpp’ where it shows how to set multiple motherboard
addresses, and a GNU Radio forum post that Josh answered at
http://lists.gnu.org/archive/html/discuss-gnuradio/2013-05/msg00417.html
where he suggests the possibility.