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Focus On CDMA |
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CDMA2000 Subscriber Growth History:
By Leon Perlman, Editor CellularOnline What
is CDMA? There are now different variations, but the original CDMA is now known as cdmaOne.
We now have cdma2000 and its variants like 1X EV, 1XEV-DO, and MC 3X. The refer to variants of usage of a 1.25Mhz channel. 3X uses a 5 Mhz channel. Wideband CDMA that forms the basis of UMTS 3G
networks, Developed originally by Qualcomm, CDMA is characterized by high
capacity and small cell radius, employing spread-spectrum technology and a
special coding scheme. Over 35 countries have either commercial or
trial activity ongoing. There are already 43 Wireless Local Loop (WLL)
systems in 22 countries using cdmaOne technology. Worldwide resources are being devoted to roll out third-generation CDMA technology, including Multi-Carrier (cdma2000 1xMC and HDR in 1.25 MHz bandwidth), and 3xMC in 5 MHz bandwidth) and Direct Spread (WCDMA in 5 MHz bandwidth). This first phase of cdma2000 - variously called 1XRTT, 3G1X, or just plain 1X - is designed to double current voice capacity and support always-on data transmission speeds 10 times faster than typically available today, some 153.6 kbps on both the forward and reverse links. (see more on cdma2000) QUALCOMM owns a substantial portfolio of CDMA
patents, including many ``essential'' patents that are necessary for the
deployment of any proposed 3G CDMA system, such as Multi-Carrier, Direct Spread,
and another system referred to as TD-SCDMA. A significant number of these companies'
licenses cover third-generation applications, including WCDMA, 1x and High Data
Rate (HDR). Under terms of QUALCOMM's existing 3G licensing agreements, a
licensee will pay the same royalty to QUALCOMM for 3G systems, including WCDMA,
TD-SCDMA and 1x, as that licensee pays QUALCOMM for today's CDMA infrastructure,
phones and test equipment. Enhancing today's data capabilities is the 1XRTT CDMA standard - this next evolutionary step for cdmaOne operators will provide data rates up to 300 kbps, significant capacity increases as well as extended battery life for handsets. Worldwide resources are being devoted to roll out third-generation CDMA technology, including Multi-Carrier (cdma2000 1xMC and HDR in 1.25 MHz bandwidth), and 3xMC in 5 MHz bandwidth) and Direct Spread (WCDMA in 5 MHz bandwidth). |
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