Slashdot Mirror
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?"
You could use satelite phone. It has the best cover, albeit being expensive.
hth
Last time I was in Greece, I just went into a Vodaphone, bought a prepaid SIM, installed it and I was on my way. Easy as pie (mostly :-)
By the way, for all the admins that are wondering... The GPRS data latency makes using your laptop to ssh in your *nix boxes workable, but frustratingly slow. The phone works great with linux tho-
First I would recommend looking seriously at the CDMA network or one of the other 2.5G networks. There is going to be a shift away from GSM over the next few years towards 3G (third generation) phones. While the uptake isnt quite what has been expected in Asia, it is comming.
There are dual CDMA and AMPS phones available here in Australia that were introduced to cover the phase out of the AMPS network. They support all new digital features, including short message service (SMS), call forwarding, call waiting, caller identification and voice privacy.
GSM doesn't like hilly regions, so if you are planning regular trips into "hilly" regions then CDMA or AMPS would be a better system. However if you are a "city slicker" then GSM is for you!
A quick google search allowed me to find quite a few CDMA/AMPS phones.
Does it go on forever?
I think it's because the 900MHz spectrum was already set aside as unlicensed. It's the frequency used by many cordless phones and baby monitors.
--Be human.
Personally I recommend a tri-band GSM phone. That will cover you in nearly every country in the world.
:)
CDMA is a good standard.. Very fast data compared with GPRS (CDMAx1=144Kb/s theoretical vs GPRS=40.2Kb/s) but over all, I find that its limited use globally makes it way too restrictive for my use.
With Tri-band GSM (800/1800/1900) you cover all five major continents. You're covered for Europe, Africa, Asia/Pacific, and Nrth America. Very useful if you just want a phone. Due to the limited release of GPRS, you may have to rely on 14.4Kb/s GSM Data (9600bps in some places) or if you're lucky, HSCSD (High Speed Circuit Switched Data) at 42.0Kb/s (mostly in Europe).
There are also phones like the dual band Treo 270 (GSM 800/1900) (also note, the Treo 300 is a CDMA phone) that will cover you for Europe, Asia and the Nrth American continents but when you're on Safari in Africa somewhere, its not usable.
AMPS is pretty limited. In fact, most places have phased it out by now with it kept purely for backwards compatibility and it has a very limited life span now. I'd say good luck buying a phone now that could still handle it and works across all regions. New Zealand (my backyard) has phased it out a long time ago, TDMA replaced it before CDMA replaced that. GSM was the catalyst for that progression when Bell South (who has since sold their GSM network here to Vodafone in the early 90's) originally set up shop in NZ in the 80's.
I personally run around with a Nokia 7650 (dualband 800/1800). I don't go to Canada too often so that when I do, its viable to rent a phone. I am intending to purchase a Nokia 3650 (GSM/EGSM 800/1800/1900) next year to solve that problem. That and MMC cards are sorely missed in my 7650.
The convenience of being able to just plug a sim card in to any phone is a huge bonus. Makes number portability a real sweet deal
GSM uses three frequencies, depending on which bastardization you use: 900, 1800, and 1900 MHz. One is Europe's standard; the other two are used in the US and Canada because the American government enjoys giving away frequencies without stopping to think what they're used for elsewhere in the world. In this case though, I think the Restoftheworldian frequencies are reserved for military use.
Anywho, you can purchase phones that support all frequencies, but they cost more. The Motorola V60 is such a phone, as are any expensive Nokias. You may be looking for a 'world phone', as some people advertise them.
You can also get tri-mode phones. The phone I'm going to pick up next week is such a phone, and has digital 1900 MHz reception if it finds a Telus tower; if not, it looks for a digital NB Tel/Aliant tower (local telco's cheaper PCS service), and if not that, then analog, if any (and most of my country's population is covered by analong at least, with the exception of my roommate's hometown, about which I mock him).
Your best bet is to find a good cellular provider (Verizon in the US), and go in and ask THEM. THey have all the answers about the phones they offer and the services that go with them. Slashdot is a bad place to go for anything but theoretical discussions and anecdotes.
Good luck.
--Dan