What is the difference between the REFin and PPSin? May I use the PXI 5652 to synchronize USRPs?

[Jay_c]

Hi, everyone!

I am working on a project which I need to synchronize 8 USRPs(USRP 2920) as receivers. And it seems that PXI 5652 has a REF out connector, so I decide to use it as the reference clock of the 8 USRPs. But I do not know how to connect the PPSin, and in fact I am confused of the difference between the REFin and PPSin.

thanks!

[vvkakade · Accepted solution]

Hi Jay_c,

In brief,

Ref In is the terminal for the USRP device to accept a external reference frequency signal (10Mhz).

PPS In is the terminal for the USRP device to accept a external time base clock source signal (1 pulse per second )

You can refer to this white paper for a detailed description about 8*8 MIMO system.

Please refer to the "Timing and Frequency"  section for information specific to your question.

http://www.ni.com/white-paper/14311/en/

I am not sure whether you can use the 5652 signal generator specifically for your application.