Thanks both,
All good now - I get a roughly constant phase
delta and when I re-run the FG, I get a different phase delta ( I
don't need to power cycle the USRPs). Now I will put in the
synchronisation code and the phase offset should be close to zero.
Kind Regards,
John
On 12/09/17 21:12, address@hidden wrote:
Use "unknown PPS" on both of them. The MIMO cable shares both
REFCLOCK and 1PPS signals, so they will both be synchronized to
the same time.
On 2017-09-12 16:13, John Shields wrote:
Thanks Derek,
No, I hadn't been power cycling between
the runs - good point, obviously, I should have.
In terms of the 10 MHz and 1 pps
references, in the configuration I was testing, I don't
believe so in that I had the MIMO cable disconnected. My
strategy was to have 2 USRPs with no MIMO - expecting little
synchonisation. Then I was going to add the devices into the
same container and connect the MIMO cable and expected things
to improve and lastly, I was going to hand-code the SBX phase
synch code.
In terms of the version of UHD, the fg
shows: <<< Welcome to GNU Radio Companion 3.7.11.1
>>>
Thanks Marcus,
I will implement your way of measuring
the running phase offset and also thanks for correcting my
understanding of O/B GPS .
In terms of getting the devices in the
container to be the best synch they can be, I presume for the
device which has the GPS, for the clock source and time
source, I would put O/B GPS for the device which has it and
for the other, I would put MIMO cable for both but in terms of
the 'Sync' field, where the options are PC Clock, Unknown PPS
and Don't Sync, which option should I select?
Thanks again for your help.
Kind Regards,
John
On 11/09/17 09:00, Derek Kozel wrote:
Hi John,
Are you power cycling the USRPs between tests or just
rerunning the GRC flowgraph? Do you have shared 10 MHz
and 1 PPS references? What version of UHD is printed
in the output?
Thanks,
Derek
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