USRP2 support to 802.11-like schemes

GNU Radio
1

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

2

Yihu Li wrote:

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 G.
Research Assistant
Communications and Signal Processing Lab
Oklahoma State University
http://cspl.okstate.edu
[email protected]
[email protected]

3

Hi Doug,

Thanks. May I ask what your cpu speed is? And what CPU can match the
capacity of USRP2?

BTW, I don’t have USRP boards yet. I will try your updated bbn 802.11
code
when I get the boards.

Yihu
On Mon, Dec 8, 2008 at 2:17 PM, Douglas G.
<[email protected]

4

Yihu Li wrote:

Hi Doug,

Thanks. May I ask what your cpu speed is? And what CPU can match the
capacity of USRP2?

BTW, I don’t have USRP boards yet. I will try your updated bbn 802.11
code when I get the boards.

Yihu

My development system is a Core2 Duo @ 2.0Ghz.
Doug

–
Doug G.
Research Assistant
Communications and Signal Processing Lab
Oklahoma State University
http://cspl.okstate.edu
[email protected]
[email protected]