Re: [Discuss-gnuradio] Synchronized transmission with two USRP2s with independent ethernet port

[hanwen]

I called sync_every_pps(), and set the timestamp of every frame to 999999999. Now I can align the transmitted samples when interporlation rate higher than 10 but not for above. I guess this it is because the datarate is too high which the buffer on USRP2 can not accommordate. Am I right? What's the size of the buffer for samples from host?

 

Hanwen

 

2009/9/23 Doug Geiger <address@hidden>

hanwen wrote:
> Hi,
>
> We've achieved synchronized receving with two USRP2s with independent
> ethernet port. I'll report in another thread. Here we are beginning to
> build a MIMO transmitter. The question comes again regarding how to get
> the samples to two USRP2 aligned. I tried to set the timestamp of
> metadata in tx_sample.cc in order to schedule the transmit occasion. But
> it seems doesn't work. Still we are using external common 10MHz ref and
> 1PPS.
>
> Thanks in advance.
>
> Bests,
> Hanwen

Are you calling sync_to_pps() for both USRP2's before transmitting to
ensure the internal clocks are aligned?
 Doug

--
Doug Geiger
address@hidden
address@hidden