This year, Electronic Design's annual Technology Forecast Issue included a diagram of the path to 3G. It showed an eventual convergence of 3G systems in the not-too-distant future. Well, it doesn't look like this will come about very soon, if ever. The new diagram for the path to 3G is revealed in this new figure.
Because of licensing and compatibility issues, it's likely that many of the 3G standards will be deployed concurrently. In Europe, for example, a single standard, GSM, is presently deployed. Operating licenses are granted by technology type. There are no guarantees that a 2G operator will be given a 3G license. Any operators not granted 3G licenses will simply continue operating 2G networks. They will use 2.5G technologies to take their networks as far as possible toward 3G characteristics and features.
In the U.S., multiple standards exist. Licenses are for spectral bandwidth rather than technologies. Network operators, utilizing versions of both TDMA and CDMA, will move to 3G. But they also will want to protect their installed networks. As they upgrade to 3G technology, they will require the assurance that the new networks are backward compatible with their original technology.
These conditions explain why, as the industry takes the next step toward 3G, several paths are emerging. The 3G segment shows some of the initial proposals for the worldwide standard which were made to the International Telecommunications Union in June of1998. Each newly formed standard delivers greater bandwidth through high chip rates, multicarrier transmission, or a higher-order modulation scheme.
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