Re: GRC with two URSP2+DBSRX and UHD

Thomas,

For this to work, one of the devices should provide its sync to the
other device.

Unfortunately, this does NOT happen automatically. You need to
configure one to drive its (reference) clock over the cable and the
other to use the signal provided by the cable.

This is pretty easy to do (but, I can only tell you how to do it in
C++)…

set_clock_config() in UHD
-or-
config_mimo() in Raw Enet/GnuRadio

I’m sure there’s some sort of equivalent in GRC, I just can’t tell you
what it is because I’m not familiar with that.

Hope this helps,

–Bob

Hi Bob,

This is pretty easy to do (but, I can only tell you how to do it in C++)…

set_clock_config() in UHD

Do you have some code snippet to share? Does the C++ version support
streaming data from a slave device through a host URSP2 before sending
all data via a single ethernet cable?

I am implementing our passive radar in C++ but I thought that GRC is
nice for testing. I learnt yesterday that things are not completely
available for GRC. But as our project needs to move on I would be highly
interested if you can sync (PPS and freq.) two (or more) URSP2s via MIMO
and (!) stream the data via a single gigabit Ethernet cable with the
current UHD library? This would enable us to place our receivers at
arbitrary locations without the need of pulse generators and a 10 MHz
reference.

Regards,
Thomas


Dr. Thomas H.
Space-Time Measurement Project
Space-Time Standards Group
New Generation Network Research Center
National Institute of Information and Communications Technology

4-2-1 Nukui-Kitamachi, Koganei
184-8795 Tokyo
Japan