Re: [Discuss-gnuradio] USRP2 support to 802.11-like schemes

[Douglas Geiger]

Yihu Li wrote:
> Hi,
> 
> I am new to gnuradio and trying to do some work based on 802.11. Through
> my understanding, the current implementations of 802.11-like schemes
> over gnuradio are mostly limitted by the processing delay on and between
> the host computer and USRP boards, eapecially due to the bottleneck of
> the USB connection between the USRP and host computer. Due to such delay
> limitations, in the implementations to 802.11 with USRP, the bandwidth
> has to be scaled down and some tuning to the IFSs has to be done to make
> the implementation work.
> 
> Now USRP2 offers Gigaehernet connection and more powerful signal
> processing hardwares. To what extent USRP2 solve the limitations of
> implementing a full-powerful 802.11 over the current gnuradio framework
> (together with the new m-block)? Besides USRP or USRP2 boards, any other
> issues mattered? Do we still need to scale down the bandwidth and tune
> the IFSs? Are there any working implementations or studies which fully
> exploited the newest gnuradio framework?
> 
> Thanks a lot.
> 
> Yihu
> 
> 

I'm working on this right now as well.  At the moment I'm working with
the original BBN 802.11b stack, modified to work with the hier_block2
API.  The problem I'm running into now is the amount of CPU required on
the host PC to work with the amount of data the USRP2 can put out.  For
the moment I'm trying to get around that by doing the processing
off-line, and plan on investigating a few ways to cut down on the amount
of CPU needed (i.e., besides just buying a faster machine).
 Doug

-- 
Doug Geiger
Research Assistant
Communications and Signal Processing Lab
Oklahoma State University
http://cspl.okstate.edu
address@hidden
address@hidden