Re: [Discuss-gnuradio] USRP2 + UHD MIMO implementation

[Josh Blum]

You may want to use the uhd_multi_usrp_blocks. They handle alignment and
synchronization in the driver. They can be used with and without the
MIMO cable. That is to say, that the MIMO cable is transparent to the
operation.

-Josh

On 01/21/2011 06:41 PM, Yong J. Chang wrote:
> 
> Hi all,
> 
> I'm working on implementation of MIMO system based on USRP2+UHD.
> I used MIMO method #3, which uses 10Mhz and 1PPS external reference clock.
> Also multiple USRP2s are connected to one PC though multiple Gbit Ethernet
> connections. 
> 
> I used multiple uhd_single_usrp_source and uhd_single_usrp_sink blocks to
> create MIMO.
> They are also connected to traditional GR blocks with some modifications. 
> 
> After aligning two timetags, synchronization is pretty much satisfied. 
> 
> However, using multiple uhd_single_usrp blocks seems not clever.
> I just look over uhd_mimo_source and  uhd_mimo_sink block codes. 
> 
> Are they just for MIMO cable setup?
> 
> ps: is there anybody who built a MIMO system with more than two antenna
> using USRP2s?
>      I want to talk with them seriously. =)
> 
> 
>