In the early nineties, GSM was deployed in many European
countries. GSM offered for the first time international
roaming for mobile subscribers. The GSM's use of TDMA as
its communication standard was debated at length. And every now
and then there are big discussion whether CDMA should have
been chosen over TDMA.
If you want to know more about GSM, TDMA, CDMA
and oa, just read a book about mobile communication.