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America's 3rd Generation (3g) Wirless Race 10/2001
The Technology Behind the 3G Evolution CDMA's evolution to 3G will be a bit more straightforward. The migration to 3G for CDMA will move from its current 2G speeds of up to 14.4 Kbps, to a 2.5G standard called IS95B. This 2.5G technology utilizes the same spectrum, but offers speeds up to 64 Kbps. The next step will involve carriers moving to a realm known as CDMA 2000. CDMA 2000 will begin with a 1X version, then move to 2X, and reach full 3G capacity at 3X. The 1-3X represents the various steps that CDMA 2000 will take before reaching its full 3G capacity. "Upgrading networks to 1X will facilitate data rates up to 144 Kbps. Once networks are upgraded to CDMA 2000 wireless transmission should be able to achieve speeds of up to 2 Mbps. To migrate through these steps, carriers will basically only have to change a channel card in their base stations, which will allow them to continue to utilize their infrastructures. The speed of this migration is a true economic incentive for carriers" says Perry LaForge, executive director of the CDMA Development Group (CDG). LaForge contends that upgrading to 3G will be a much more cumbersome process for those currently using GSM and TDMA. IMT-2000 (International Mobile Telephone Standard) is a framework developed by the International Telecommunications Union that is designed to set global standards and spectrum allocation for 3G. Under these guidelines 3G packet-based technology is capable of 144 kbps in a moving location, such as a car or train, and up to 2 Mbps in a fixed location. These guidelines also spell out the capability of global roaming, which is not possible using today's wireless technology. IMT-2000 offers support for both W-CDMA and CDMA 2000. Figure 3.1 shows the roadmap that must be followed by these competing technologies, in order to reach third generation wireless. Figure 3.2 illustrates the projected growth rates of the different technologies. Chart 3.3 provides reference definitions for each of the different technologies associated with 3G.
Figure 3.2
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