GSM in the U.S.

GSM Carriers in the U.S.
Two major U.S. carriers are deploying GSM networks in the U.S., AT&T Wireless, and Cingular. A third carrier, T-Mobile has always been GSM. Cingular launched GSM service in 2002 in New York City. AT&T is now migrating from TDMA to GSM. AT&T probably has the best cellular network in the U.S. based on its TDMA and AMPS networks. All of AT&T Wireless's affiliates are also moving to GSM.

GSM Coverage Varies by Region; In some regions it's great, in some it's fair, in some it's non-existent.
GSM coverage in the U.S. varies by region. In urban areas where T-Mobile has had a long presence (previously as Voicestream) the GSM coverage is pretty good (i.e. the eastern seaboard). In California, it's fair, and it is improving as AT&T overlays GSM onto their TDMA network. When AT&T and Cingular complete their conversion to GSM and when they have 800 Mhz GSM coverage as well as 1900 Mhz, GSM will indeed be competitive in terms of coverage (except for the lack of AMPS). GSM handsets lack the AMPS capability that is present in most CDMA and TDMA handsets. This means that you will have no coverage in many rural areas where AMPS is the only wireless system.

I recently visited Alaska. There is no GSM service in the entire state, except perhaps a tiny amount on one island (no Nextel service either). There is no GSM service in Vermont. You can look at some of the GSM coverage maps over at http://www.gsmcoverage.co.uk/maps_go/namerica_init.html . In five years or so, GSM coverage will likely be equal to CDMA, but even then you'll want a phone that includes AMPS for areas with no digital coverage of any kind.

How Did AT&T Wireless Come to Choose GSM?

AT&T Wireless was all set to move to CDMA (see: http://www.lucent.com/press/0895/950824.nsa.html and http://www.thestreet.com/comment/wirelesswiz/1193961.html until they were swayed by a 9.8 billion dollar investment by Japan's NTT Docomo. Now AT&T Wireless is in a panic trying to roll out W-CDMA in four cities by the end of 2004 (this agreement was renegotiated from a commitment to roll out W-CDMA in thirteen cities by mid-2004), see: http://www.nwfusion.com/news/2002/1231attwirel.html. As someone pointed out, AT&T Wireless is no longer part of AT&T, it's a separate company. But in 1995, AT&T Wireless was indeed part of AT&T. The two companies didn't separate until July of 2001. 

Everyone in the wireless industry expected AT&T to convert their TDMA network to CDMA, and that Cingular would fall into the CDMA camp as well. A big pile of money changed AT&T's mind. It was a huge blow to Qualcomm. AT&T chose GSM as a result of the investment by NTT Docomo, not because it was the better standard. As stated in the article Qualcomm faces conundrum , "Late last month, Japan's NTT DoCoMo (OTC : NTDMY ) agreed to acquire 16 percent of AT&T Wireless (NYSE : AWE ). As part of the deal, AT&T decided to spurn Qualcomm's CDMA technology in the near term and build out a GSM network in the U.S." 

AT&T made this decision freely; they wanted the money from NTT Docomo, and moving to GSM and W-CDMA was the price they had to pay.

GSM's Challenges in the U.S.

Spectrum Availability
In Europe, separate spectrum has been allocated for voice and data on GSM; in the U.S., voice and data must share the same limited spectrum. AT&T will have sufficient spectrum for W-CDMA once they turn off their TDMA and AMPS services, but Cingular cannot go beyond EDGE due to lack of spectrum.

Coverage
800 Mhz TDMA, 800 Mhz CDMA, and 800 Mhz AMPS offer far better coverage than 1900 Mhz GSM. It is not an issue of GSM versus CDMA, it's an issue of 800 Mhz versus 1900 Mhz. To duplicate the existing coverage of TDMA, CDMA, and AMPS will require years of siting and constructing new cells. It is an over-simplification to state that a carrier is overlaying GSM onto TDMA because they need far more 1900 Mhz sites to provide the same coverage as 800 Mhz TDMA. The alternative, and one which is coming in a few years, is the wide deployment of 800 Mhz GSM. When this rollout occurs then GSM will at least be more usable in urban and suburban areas, and inside buildings. Most GSM service in Europe and Asia is at 900 Mhz.

1900 Mhz PCS versus 800 Mhz Cellular & In-Building Penetration
Most GSM service in the U.S. has been at 1900 Mhz because the more desirable 800 Mhz spectrum is being used for TDMA, CDMA, and AMPS, which were here first. This is changing as the existing 800 Mhz TDMA carriers deploy GSM in the 800 Mhz spectrum, but ubiquitous 800 Mhz GSM is a long way off. 1900 Mhz PCS uses lower power cells which requires more cells, and the higher frequency also means that more cells are required. T-Mobile has no 800 Mhz spectrum and no plans to get any. There is further information on the in-building penetration issue at the site: http://www.arcx.com/sites/CDMAvsTDMA.htm (remember that GSM is just one type of TDMA).

AMPS (Analog) fallback
The AMPS analog cellular system is still the only system in many rural areas. Furthermore, AMPS cells cover a much wider area than digital cells of any kind, so in areas where no cells are permitted (i.e. National Parks) you can often get AMPS coverage from surrounding areas. No for-profit carrier is going to install CDMA or GSM cells that will cover the areas that AMPS currently covers. Perhaps the government needs to fund a program similar to the Rural Electrification Authority to provide service in areas that are not economically viable enough for a for-profit carrier to cover.

Most CDMA phones include AMPS capability. Two GSM phones do. Cingular does offer two phones with AMPS, the Nokia 6340i and the Sony-Ericsson T62u (though these are not offered in New York City), AT&T now offers the T62u.

International Roaming
With a tri-band (or quad band) GSM phone (900 Mhz, 1800 Mhz, 1900 Mhz) a subscriber can roam internationally in most of Europe and much of Asia (not Korea or Japan). However there is a way to achieve the almost same result (but not as cleanly) at a much lower cost. Buy a low cost unlocked GSM phone that supports 900 Mhz and 1800 Mhz, and buy prepaid SIM cards in the country you visit. Even GSM users in the U.S. will often buy prepaid SIM cards in Europe and Asia because it is cheaper than doing international roaming.

Handsets
There is a much better selection of GSM handsets than of TDMA or CDMA handsets, and at lower costs. The market for CDMA handsets is much smaller and hence commands higher prices. On the other hand, CDMA handset growth is greater than GSM, as emerging markets such as India and a lot of China are installing CDMA networks, so there are still new and improved CDMA handsets being designed and manufactured.

Repairs
If your GSM phone breaks you simply move your SIM card to another GSM phone. You can buy a spare GSM phone pretty cheaply if your carrier does not provide loaners. If your CDMA phone breaks you have to buy a replacement at a high cost.

What does all of this Mean to You?
If ubiquitous coverage is important to you that you should choose a TDMA or CDMA carrier, with AMPS, that operates an 800 Mhz network in the areas that you frequent the most.

As the author of the Oregon and Pacific Northwest Cell Phone Information site wrote:
"I continue to read horror stories from folks who are sorely disappointed with AT&T's GSM system in various places around the country. If you choose AT&T, stick with their TDMA/analog offerings which are infinitely superior to their GSM plans at this time. Yes, AT&T's GSM will eventually be the way to go (at least if you choose AT&T) but it's really not "there" yet. You've been warned :)"

Respected industry analyst Andrew Seybold, in a Wireless Week interview, stated: 
"I talk to LOTS of folks who are NOT happy with their NEW GSM coverage over what they had with their TDMA system."

The Future of GSM in the World
A mobile failure waiting to happen
The final blow is the unbridgeable gap between selling the concept and facing up to the reality (from The Guardian)

Time for plan B
A technological escape-hatch exists for Europe's troubled mobile operators. But they are not allowed to use it (from The Economist)

USS Clueless
CDMA, 1. It's impossible. 2. It's infeasible. 3. Actually, we thought of it first. A funny, but true account of the GSM misinformation campaign about CDMA.

Some Funny TDMA versus CDMA stuff from the Past
In the "I wish the Internet didn't exist" department, read these hysterical, 1995 and 1995, anti-CDMA, Qualcomm hit pieces, by Bill Frezza, whose company did consulting for TDMA system vendor Ericsson:

Succumbing To Techno-Seduction (1 April 1995) and CDMA: Blazing A Trail Of Broken Dreams (15 April 1996).

Then when he finally realizes that he was totally wrong about CDMA he grudgingly writes: 

CDMA: The Revenge Of The Nerds

Nothing seems to change! A new crop of anti-CDMA zealots continue to spout lies about both CDMA and GSM. I'm going to broker a peace treaty. Here's the deal. The GSM advocates will stop telling lies about CDMA, the CDMA camp will stop telling the truth about GSM.