Robert,
This is a easy solution here:
Commotion-OpenBTS
==Introduction==
Commotion-OpenBTS is packaged as a customized x86 Ubuntu Linux distribution.
It comes as a live image that can be booted from a USB drive or CD. This
repository contains resources used to create the Commotion-OpenBTS image.
The purpose of this software is to allow voice calls over a Commotion
wireless mesh network. Phone calls can be made between GSM unlocked phones,
or between GSM unlocked phones and phones meshing over WiFi with the Serval
"Batphone" software.
In order to use Commotion-OpenBTS, you need a compatible GSM hardware
transceiver. Currently, compatible hardware includes the Range RAD1;
the Ettus USRP1, USRP2, N200 series, B100 series, and E100 series; and
the Fairwaves UmTRX.
==How to Run It==
To run Commotion-OpenBTS, download the ISO file at
unetbootin, or your tool of choice. You can then boot from the USB drive
with your laptop or desktop computer, with your GSM radio attached. Once
the OS is loaded, a configuration wizard asks you what type of GSM hardware
you have, and configures the proper driver. After that, everything should be
running, and you can start making calls!
==Components==
Commotion-OpenBTS includes the following open source software components:
http://files.opentechinstitute.org/~critzo/commotion/Commotion-OpenBTS-x86.iso
Just utilize the Commotion-OpenBTS-x86.iso and it *should* work for both the USRP1 and the UmTRX.
Only one application can access the SDR device of your choice at a time.