Clock Synchronization Question

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Clock Synchronization Question

Post by DocJava » Tue Jan 22, 2019 12:54 am

I recall reading a few years ago about there being some work done on clock synchronizing captures from multiple bladeRF devices all at the same time. (I don't recall any of the URLs pointing to the relevant info unfortunately).

I noticed several u.fl connectors for clock in/out on the bladeRF xA9. Is it officially supported now to synchronize clocks among say 2 to 4 radios at the same time? Perhaps with full support in libbladeRF?


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Re: Clock Synchronization Question

Post by bglod » Tue Jan 22, 2019 2:08 pm

I could be wrong, but to my knowledge, this has always been supported via the trigger in/out pins on J71 for bladeRF1, and J51 for bladeRF2.

The bladeRF devices also have the ability to receive or transmit an external 38.4 MHz clock (SMB port for bladeRF1, J93/J92 on bladeRF2). The bladeRF2 also has a REF_IN U.FL (J95), which is routed to an analog PLL. When a reference clock is present and the analog PLL is enabled, the frequency and phase of the onboard VCTCXO will be tamed to that reference. All of these features are fully controllable via the libbladeRF API and bladeRF-cli.
Electrical Engineer
Nuand, LLC.

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