Toward True 3G
For a long time, cellular networks in the United States have been saddled with old technology, and early attempts to offer high-speed data services left consumers more confused than connected. So-called 2.5G standards--which didn't quite reach anticipated 3G network speeds (for 3G, 300 kilobits per second is widely considered a rough lower bar)--were ultimately disappointing. Frustrated users of 1xRTT (the 2.5G technology deployed by CDMA carriers Sprint and Verizon) or EDGE (the slightly faster 2.5G technology adopted on the Cingular/AT&T side) regularly received harsh reminders of their service's similarity to analog dial-up: None of these services could manage speeds much higher than 60 kbps or so in the real world.
Enter 3G. With eyes on wireless data speeds that can match those of DSL, a revolution is finally under way. Two main 3G technologies are currently rolling out in the United States. The first--and more widely deployed--is EvDO (Evolution Data Only, or Evolution Data Optimized). An update to the CDMA radio technology used by Sprint and Verizon in the United States, EvDO provides very high data throughput, with a theoretical maximum speed of about 2 megabits per second.
Even so, the GSM-based networks (run by Cingular and T-Mobile), although trailing, aren't out of the game. The 3G version of GSM, called HSDPA (High Speed Downlink Packet Access), is newer than EvDO and is being launched just now by Cingular. We were able to do only some last-minute tests in San Francisco (see "HSDPA vs. EvDO: Cingular Starts Its Own Broadband Service"). HSDPA speeds theoretically can reach 3 mbps and faster--so fast that some people call HSDPA a "3.5G" service. T-Mobile won't launch HSDPA here until 2007.