Subject: proposed change to ugen to enable USRP to work
To: None <>
From: Greg Troxel <>
List: tech-kern
Date: 05/03/2006 13:58:56
At BBN we are working on a project involving teams of
cognitively-controlled software radios, funded by the US government.
As part of this, we will be using GNU Radio on NetBSD (which Berndt
has placed in pkgsrc).  The Universal Software Radio Peripheral (USRP)
is "software radio hardware", and attaches via USB.  Due to the
current implementation of ugen(4), reads from the USRP are not
pipelined and transfer rates top out at around 4 MB/s, compared to 32
MB/s on Linux.

Joanne has written a proposal to modify ugen(4) to get good
performance for the USRP.  We'd like feedback about the technical
approach, both on its own and about including the results in NetBSD.
(Once we have it working, I'd like to commit the changes to -current.)

        Greg Troxel <>