The problem is, they won't be able to use GPRS, UMTS, HDSPA, LTE or WiMax, they will have to come up with a 100% new technology, which doesn't rely on any of the same techniques as the existing methods of wireless communication.
Once they have that sorted, they will have to come up with a totally new method of encoding voice digitally.
Then a way of transferring data between a handset and a basestation, which isn't already patented...
And we haven't even got to the point, where they can make an operating system! Making an OS that is unencumbered, today, is nearly impossible.