900MHz packet radio?

[Paul Gardner-Stephen]

Greetings all,

At the Serval Project we have created a mobile mesh telephony system
that currently works over wifi.

>From the outset, we have wanted to get it working on the ISM915 and/or
ISM868 bands that are located adjacent to the GSM 850/900 frequency
allocations.

My initial investigations and enquiries indicate that this should be
possible by creative programming of the baseband processor in many
models of phones.  The trick, as I suspect you well know, is the
difficulty in getting the information and tools required to reprogram
these radios.

I am now in a position to potentially fund further work on this.

So, as the open-source group with the most experience reprogramming
baseband radios, what is the feasibility of creating a
proof-of-concept using the types of phones you already work with to
send and receive arbitrary data packets without reliance on a cell
tower (even for time synchronisation)?

I know there are a lot of constraints and problems, but I am most
interested in creative solutions that can get us to a working
prototype, however crude, that can be used to demonstrate the
feasibility of what I am proposing.

If this discussion is off-topic here, I am happy to hold the
conversation at the serval-project-developers google group, but I am
equally comfortable with it continuing here.

Thanks in advance,
Paul Gardner-Stephen.
Shuttleworth Telecommunications Fellow at Flinders University.