2G networks (GSM, CDMAOne, D-AMPS) are the first digital cellular systems launched early 1990s. 3G
networks (UMTS FDD and TDD, CDMA2000 1x EVDO, CDMA2000 3x, TD-SCDMA,
Arib WCDMA, EDGE, IMT-2000 DECT) are newer cellular networks that came
to the U.S. around 2003 with data rates of 384kbit/s up to 2-3 Mbits/s.