Interesting article from Telecom Magazine
In US Sprint Nextel and Verizon Wireless fly the flag for CDMA2000, while AT&T and T-Mobile USA spearhead the W-CDMA charge.
So far, CDMA2000 clearly has taken the high ground. Verizon laid claim to about 60.7 million CDMA2000 customers by the end of March 2007, while Sprint Nextel said it had captured 53.6 million. The W-CDMA operators, by comparison, could muster just 2.5 million customers between them.
The CDMA Development Group (CDG), which lobbies for CDMA2000, attributes this gulf to a technology lead. CDMA2000 operators, it notes, have deployed enhancements like EV-DO Revision A, which can deliver speeds of up to 3 Mbps for VoIP and multimedia applications. W-CDMA, in stark contrast, is still unavailable in many parts of the U.S. Even where it has been deployed, it typically is capable of a far less impressive 384 kbps.
W-CDMA, however, is definitely on the march. AT&T and T-Mobile USA are planning rollouts using HSDPA, a W-CDMA enhancement that offers speeds of up to 3.6 Mbps. More importantly, while W-CDMA’s customer base of 2.5 million appears low when judged alongside CDMA2000, it has grown from just 350,000 late last year.
“AT&T uses a higher frequency [than its CDMA2000 competitors], which is a disadvantage,” explains Allen Nogee, a principal analyst with In-Stat.
Generally, U.S. operators have deployed CDMA2000 using spectrum in the 800 MHz or 1900 MHz bands, while AT&T is rolling out W-CDMA using 2100 MHz spectrum. The lower frequencies have better propagation characteristics, allowing CDMA2000 operators to serve a wider area using fewer base stations.
Generally, U.S. operators have deployed CDMA2000 using spectrum in the 800 MHz or 1900 MHz bands, while AT&T is rolling out W-CDMA using 2100 MHz spectrum. The lower frequencies have better propagation characteristics, allowing CDMA2000 operators to serve a wider area using fewer base stations.
“AT&T is also in a transitional phase,” Nogee adds. “Although it can advertise its new HSDPA network, that network has not been rolled out everywhere yet.”
Meanwhile, T-Mobile USA, the fourth largest operator in the U.S., plans to launch a W-CDMA service using the 2110 MHz to 2155 MHz spectrum it purchased in last year’s auction for advanced wireless services. Although it did not respond to requests for an interview, T-Mobile USA previously issued a statement on its 3G intentions in which it says the company will transition to a next-generation technology, which may include W-CDMA/UMTS with HSDPA, in the next two-to-three year timeframe.
And finally we cannot have a discussion without looking at the future (4G?):
Although W-CDMA is still in its early days in the United States, operators already are thinking about the next generation of mobile technology.
While a 4G standard is not yet defined, marketing departments are applying the label to some technologies already in development.
While a 4G standard is not yet defined, marketing departments are applying the label to some technologies already in development.
For W-CDMA operators such as AT&T and T-Mobile USA, the technology typically viewed as 4G is called long-term evolution, or LTE. It represents the destination on their journey through upgrades to HSPA, but will use a different air interface called OFDMA and require more work. Theoretically LTE will deliver downlink speeds of 100 Mbps and uplink speeds of 50 Mbps.
CDMA2000 operators also have 4G in their sights in the shape of EV-DO Revision C. Like LTE, Revision C promises vast improvements over the current crop of wireless standards. Allen Nogee, a principal analyst with In-Stat, thinks both LTE and Revision C could see commercial deployment by 2010.
In the meantime, Sprint Nextel has been vocal about another 4G technology. Last year, it earmarked US$2.5 bn for investment in a nationwide deployment of WiMAX, using 2.5 GHz spectrum it already owned. WiMAX proponents have made some bullish claims about its capability (promising up to 70 Mbps on the downlink), but the technology has not evolved from other standards—unlike LTE and Revision C—and will lack any scale economies when it is launched next year.
Chris Pearson, president of 3G Americas (a lobby group for W-CDMA), is unconvinced by the WiMAX business case. “It’s a wild card. In our view, most subscribers will be using W-CDMA and EV-DO for years to come.”
3 comments:
i think that the article has a few fundamental errors.
AT&T is the only one WCDMA operator in the country.
HSDPA is already deployed by At&t. AT&T uses for 2G and 3G the same frequency that CDMA: 850 Mhz and 1900 Mhz.
LTE is not a 4G technology, it's an evolution of 3G and it is still 3G. The generations are defined by the ITU and there is not a definition for 4G yet(Wimax isn't 4G either).
The equal to LTE in CDMA world is UMB
Hi Daydalaus,
I agree with some of your comments as you have properly said, LTE is not 4G. I was copying from the article and didnt want to pick up on the author. Nevertheless some people refer to WiMAX and LTE as 4G. Referring to WiMAX as 4G 'sexes' it up.
T-Mobile has already launched its WCDMA network in US. They are a small player right now but have plans to expand the coverage and i dont think it will take them time to ramp up to speed. They have awarded the contracts to Nokia and Ericsson who are experts in these technology.
T-Mobile also has licence for 1700MHz and 2100Mhz band for UMTS but i dont exactly know which frequencies they operate in right now and what are their plans for future. But with WCDMA there is lots of flexibility for the frequency use.
T-mobile is currently building the network, but they don't have launched it commercially. The spectrum is the AWS which uses two bands the 1700 and the 2100 at the same time. 3G UMTS it's an FDD technology (such as GSM) so it needs two separate spectrum allocations, one for the uplink and other for the downlink. (this is known as 1700)
The European 3G uses 1900 Mhz for the uplink and 2100 Mhz for the Downlink, this combination is known as 2100 (easier to use in this way). AT&T uses the same approach (3G FDD) but the uplink and downlink are more closer to the 1900 Mhz (that's why this band is known as 1900)
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