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Cellphones that Work Everywhere?
spoonist asks: "The vast array of available wireless protocols in the US is quite
bewildering: CDMA, TDMA, GSM, AMPS. I spend most of my time in urban areas. Major providers appear to be rolling out GSM, so that seems like the way to go. I also spend a lot of time hiking and climbing in rural areas and like having my mobile phone in case of an emergency. My ancient analog phone gets a signal in all but the most remote of areas
LONG after friends' digital phones loose their signals. Are there any dual mode mobile phones that can talk both GSM and AMPS? Also, I occassionally travel to Europe. From what I understand, GSM in the US uses a different frequency from the rest of the world (WHY!?!).
Are there any phones that talk European GSM, US GSM, and AMPS?"
3GSM is usually known as UMTS, and is associated with W-CDMA (the commonest radio interface for UMTS). (Only the GSM Association calls it 3GSM). UMTS should be the most widespread 3G standard a there is an upgrade path for GSM operators - even though the UMTS technology is very different from GSM, handover between GSM and UMTS cells will be possible.
As for CDMA - it has been deployed at 800 MHz in Australia to replace the analogue AMPS network, primarily to provide rural coverage. An interesting comparison table for GSM and CDMA in Australia is at http://www.austarmobile.com.au/tools_netinf02.asp - looks relatively unbiased as it's from a company with a foot in both camps.
The kicker is that current 3G deployments using the CDMA upgrade for 3G (CDMA2000) are going very well in Japan and Korea, while NTT DoCoMo's flavour of 3G (W-CDMA based, similar to UMTS) is having real trouble (due to poor coverage, single-mode handsets, applications, pricing, etc). So there is a chance that UMTS won't really succeed and CDMA2000 will take over. However, given the sheer amount of investment in UMTS by Ericsson, Nokia and many wireless operators, I'd be surprised to see this happen.
Why do you care if the phone is GSM? That is the technical standard. I care that my phone works where I want to use it. GSM, CDMA, AMPS, TDMA (others?) are technical standards, and it the the phone companie's job to figgure out which is best and how to switch people to it. You problem is getting clear calls in various locations. Figgure out where you need a phone, and use it there.
Many US carriers will rent you a phone that will work in Europe, with your number, even though they don't have a GSM network.
The only advantage of GSM has over the others from a consumer stand point is anyone can remove their SIM card and put it in a different phone. (Thus you can buy a US phone, and if you travel get a europe only phone for use there) That is only an advantage that consumers need to care about. (In truth, GSM was an early standard, that like most got some things right, and some wrong, but it happened to win. Windows won the OS war long ago, but it was never the best)
Quit looking at the phone companies problems, and start looking at coverage areas, roaming charges, minutes, roaming coverage, and cost. That is what you care about.
As an aside, if you find one plan you like, but it doesn't cover everywhere, call the provider, they can only build so many towers per year, so they have to decide where. If you tell them that you want coverage someplace they might put a tower there in 6 months or so. It is worth a shot, it might or might not work.