USRP Software Radio

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Octoclock and PPS generator using USRP

I have to synchronize 2 USRP RIO 2952. So I need PPS signal and reference clock. Cannot we generate programmed PPS using one master USRP and use T shape RF splitter to distribute reference signal.

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I haven't done any testing with daisy chaining. I *do not* think this code should be used without lots of testing. I have my doubts about the synchronization repeatability from run to run, and across different systems with different cables lengths and delays. With that said...


Here's some code you can use to configure your USRPs with the USRP RIO API. If you generate a one of the Time-based Sample Projects, you can modify the host code to have this:


time daisy chain.PNG


The 0th device uses an internal reference clock and an internal PPS. The 0th device exports its reference clock and PPS to the other devices. The other devices use this external reference clock and external PPS.


Again, this approach comes with zero support and zero testing and zero recommendations! Good luck!

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I cannot see the blocks clearly can you post the vi file?

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I've attached the VI snippet to this reply.

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Thanks fot the reference figure. What I am interested in figuring out is the generator/master side. The reference figure you gave corresponds to slaves.


Can I control PPS and CLOCK outputs from USRP and make a programmable OCTOCLOCK?   


I want to design the master which will give these reference signal.

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