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Cellphones that Work Everywhere? 52

Posted by Cliff from the don't-I-wish dept.
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?"
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Cellphones that Work Everywhere? More

Cellphones that Work Everywhere?

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  • iridium! (Score:2, Informative)

    by Anonymous Coward
    You could use satelite phone. It has the best cover, albeit being expensive.
    hth
    • Sure. As long as you don't want to make or receive calls when inside a building.


      Cell phones are a commodity item now anyways. What do you think you're gonna have to pay for an "all network" phone? A metric ass load thats what. And don't forget the golden rule of multifunction devices: They'll do most things OK, but won't do any one thing *good*. Why not just purchase separate phones?

  • GSM/GPRS (Score:2, Informative)

    by Anonymous Coward
    I have a Sony Ericsson T68i with AT&T and love it.

    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-

    • I find it amazing verizon goes through all the trouble to put there service in the Holland Tunnel (NYC), yet from my apartment in midtown manhattan (31st floor) I get a shitty connection. From my work in midtown manhattan, the connection is so weak that I can't even use the phone.

      Boy, I'm glad that I can make a call for the 10 minutes that I'm stuck in traffic in the Holland tunnel. I can't seem to make/receive calls from anywhere else.

    • Comment removed based on user account deletion

  • CDMA and AMPS (Score:2, Informative)

    by scum-e-bag ( 211846 )
    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.

    • Re:CDMA and AMPS (Score:5, Informative)

      by jquirke ( 473496 ) on Sunday September 15, 2002 @05:01AM (#4260255)
      Firstly, "3G" is not a standard on its own. There is not going to be a shift away from GSM here in Australia, or in many parts of the world.

      The term "3G" is nothing more than a stupid marketing term, it explains very little and just confuses people about the technology. Hopefully I can clear up some of this confusing mess of acronyms.

      The term GSM however does not refer exclusively to the current "2.xG" digital technology. GSM is constantly evolving, and yes, will become "3G".

      The first stage in the GSM "2.5G" evolution towards 3G was GPRS (General Packet Radio Service). This extended GSM to support packet switched data over multiple timeslots (bandwidth per timeslot = 14400bps). It required little change to the GSM network except for software upgrades on the base station and other minor changes to the backbone. Hence GPRS could be called "2.75G". GPRS is implemented by all 3 Australian carriers Optus, Telstra and Vodafone. It is also implemented in many other countries.

      The next phase will be EDGE (Enhanced Data rates for GSM Evolution). Also called "E-GPRS" this is much like GPRS however it packs more data onto a single timeslot (upto 3 times as much due to improved coding (8 Phase shift keying as opposed to Gaussian Minimal Shift keying) and error correction transferring up to around 3 times as much data - 3 bits per symbol with a raw symbol rate of 270K). This only generally requires hardware changes to the radio interface of the base station. No official term for this yet, call it "almost 3G - 2.9G??".

      Unfortunately Optus scrapped its plans to implement this for now, however I've been told some of the newer GSM base stations do support EDGE.

      It is important to note that GPRS & EDGE operate in the normal GSM spectrum (thats 900MHz and 1.8GHz here in Aus and most of the world, 1900 and 800 in the US/Canada).

      The next part however is to _supplement_ EDGE in other parts of the spectrum. Branded "3GSM", I am not too familiar with the technology however I believe most GSM countries will use a Wideband-CDMA technology (W-CDMA) in the 2.0-2.2 GHz spectrum. Hence, a 3G GSM phone operates on several frequencies using several coding techniques transparently to the user. The different codings are suited to different environments so I guess you have a more reliable service. EDGE can supposedly transfer around as much as 384Kbps whilst W-CDMA can do around 2megabit or so.

      EDGE can coexist peacefully with older GPRS and "plain old GSM" transmissions on the same timeslot, so it's backward compatibility will make it look promising.

      In Australia GSM will be the way of the future here, however CDMA is still useful for the rural hicks :-) where GSM coverage is lacking. But most Australians live in cities.

      Anyway correct me if I've made errors

      --JQuirke

      • Re:CDMA and AMPS (Score:3, Insightful)

        by Cato ( 8296 )
        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.
        • The combined UMTS license costs in Germany set the Network operators back for ca 50 billion Euros.

          I'd f'cking surprised if it failed. At that price it has to work...
  • I think for example Nokia 8990 [nokia.com] should (and does) work pretty good even in the States. If you're more "robust" just buy couple of different cellphones that do the trick. Why? 8890 costs quite a bit.
    • I just went to the US last week and brought with me a 8890. I love that phone. It is one of the best looking mobilephones of all times if you ask me (which - of course - you didn't :-). I worked fine in Southern California. Too bad that the newer models taking over the 8890 segment aren't as nice. Nice to have both the features and the looks.

      My next phone is going to be the 6610 which is tri-band. Otherwise go for the better Ericsson models. They are all tri-band now. One can get trouble with a dual-band 900/1900 phone in urban areas in Europe due to scarce bandwidth. With a combined 900/1800/1900 that isn't a problem I am told.

      Cheers,

      RiF
  • In Europe, Dual band (900-1800) GSM phones with support are usually sold these days. This includes the older and newer European and Asian GSM frequency. Many offerings include so called "world band" GSM phones with 900, 1800, and 1900. This should be the GSM soulution for you since it works pretty much everywhere in the world where they have GSM, includin the States.

    I am sure you can find this type of phones in the States too, you will see Google gives you many answers [google.com].

  • I have a GSM Tri-band phone. (900, 1800, and 1900MHz) and it works on all GSM networks.

    I found I could roam all over the US using my Australian (Optus) SIM card, it just got billed to my account, and the rates were not unreasonable. (I was pleasantly suprised.) Europe and Asia are not a (technical) problem either. Receiving calls is more difficult, a pre-paid local SIM will help there. (My Ericsson "T28 World" phone dosent do AMPS, but I dont need it.)

    Just make sure that if you pick up a GSM phone, it does Tri-band, and you are covered. If you can find one that does AMPS too, all the better.
    • You might well find that it's no more expensive to send sms from another country than when you're at home. Either that, or fractionally more expensive. I think for Orange on the tariff I'm on it's 6p in the UK and 8p in Europe to send an sms.
  • 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 :)

    • I know of places in the US that have only AMPS coverage, and I don't think that will change anytime soon. I don't know how you pay for a tower that covers Chasely North Dakota (population: < 10, I have relatives that happen to live nearby, within the 36 square mile township there are 100 people)

      Sure, easy to you to say AMPS is dieing, and I don't see anyone putting in an AMPs tower anymore, but I don't see them upgraded a lot of rual towers either, at least not while they can maintain the current equipment. Eventially I expect to see upgrades, but not until a digital standard is agreed upon and looks like it will not be upgraded.

      I can justify upgrading all the cell phone towers in New York City every few years because there are a lot of users to pay for it, and presumibly demand. I cannot do the same for remote towers that are rarely used.

      Don't forget that the problems of city towers are different from rual ones. When the tower is not busy you really want to find some way to increase the range and get rid of a few towers. When the tower is saterated with calls you want to find a way to turn the power down further and split the cell.

    • Very fast data compared with GPRS (CDMAx1=144Kb/s theoretical vs GPRS=40.2Kb/s)

      GPRS Class 8 is 57,6kbps.

      GPRS Class 32 is 172,2kbps, which is a bit higher than CDMAx1.

      or if you're lucky, HSCSD (High Speed Circuit Switched Data) at 42.0Kb/s (mostly in Europe).

      Again, HSCSD is a bit faster than that. You can achieve up to 56kbps without major problems.

  • GSM and You (Score:3, Informative)

    by Sentry21 ( 8183 ) on Sunday September 15, 2002 @10:32AM (#4260683) Journal
    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

    • correction, GSM in europe uses 900 and 1800 Mhz, with either frequency having nearly full coverage. (900 filled up and carriers wanted in, I belive it was an old analog stnadard not used anymore, but I'm not sure.) Note that 1800 is double 900, and thus makes some parts of dual band radio design simpler.

      The US wanted to give 1800 to those who wanted it (at high chost), but that rage was already assigned to someone else (military?) who didn't want to give it up. So trying to be close they assigned 1900. The old US analog freq uencies are at 800 Mhz (you do see CDMA on those frequencies because the cdma people came up with a CDMA/AMPs dual base station, I've not heard of GSM there, but there is no technical reason it couldn't be done)

      Don't forget that until cell phones very few people cared about about compatablilyt of wireless standards across the pond. Other than military and a few commmercial shippers nobody really had the ability to communicate more than a few miles. The US can Canada were used to working togather because radio and TV cross the borders so they needed to be sure there was no interfierence, and it would be nice to pick up those cross border stations once in a while.

      Don't ask just the providers, ask the independant guy who sells all brands of phone. Sometimes they know the answers, and they are not biased to one service.

      • 450 and 900 MHz was used (And still is to *some* extent) in northern Europe. There still are some NMT-phones in use in Norway, but I believe the 900-network will be closed sometime 2003 (The 450-band network was closed a few years ago).
    • Dan said: 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.

      I'm looking at providers right now (I have Sprint and it just doesn't have the coverage, like when I'm sitting at my desk :-( ).

      The problem is that the dealers lie when you ask about coverage areas and stuff like that and without a road trip you really have no idea.

      That said I'm leaning towards Verizon and am going to stay away from the 3g stuff for a bit more (it is nice though).
  • If you want a phone that will work almost anywhere checkout AT&T's Siemens TDMA/GSM tri band phone TDMA/GSM tri band phone /a> . AT&T's TDMA coverage is by far the most in the U.S (compared with GSM & CDMA) and it can also be used where AT&T is sprouting up their new GSM network(CA, TX, FL...) not to mention Europe, Asia, South America.... The only country I can think of is perhaps South Korea they're using CDMA. So if you don't plan on going to South Korea. It would be a good idea to buy one off the net (costs more) that does not come sim card locked, You know, that way when you're on you're in Italy or France you can still use the same phone, it would be just a matter of swapping out sim cards with the providers that reside in that country. Also you could switch over to T Mobile at anytime. Also clearing up some mis stated comments earlier: "CDMA is a good standard.. Very fast data compared with GPRS (CDMAx1=144Kb/s theoretical vs GPRS=40.2Kb/s)" GPRS is actually 171 Kb/s theoretical, using all 8 time slots of course, However in actual use the speed is much less than theoretical, as always with any technology especially in its initial use actual is far from theoretical. Also CDMA 1X is what I believe he's refering to, CDMA is only about 19 kb/s, this is because 2G is circuit switched(time based) not packet switched like 2.5G and up. "First I would recommend looking seriously at the CDMA network or one of the other 2.5G networks." CDMA is a 2G standard ->CDMA 1X is 2.5G -> CDMA 2000 GSM is a 2G standard -> GPRS is 2.5G-> WCDMA or EDGE is 3G When you hop on a network provider with GSM this is what they'll offer you as an upgrade path to 3G over the next years. When you use 2.5G (GSM/GPRS based), you would still use GSM for voice, but GPRS for data. It's not a question of what are service providers going to, but a question of which path they choose first and then which Generation have they upgraded to. At the minimum they must have either 2G (CDMA or GSM). [siemenscordless.com]
  • I have the Motorola 120c and it works great and is web ready. The Web only works on digital networks, but other than that, it works fine on Digital and Analog networks.

  • Why do you care about GSM? (Score:3, Insightful)

    by bluGill ( 862 ) on Sunday September 15, 2002 @06:27PM (#4262425)

    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.

  • GSM and CDMA are the current contenders in the US, with VERY few GSM handsets offering analog (AMPS) capability. Verizon and Sprint are CDMA, T-Mobile (nee VoiceStream) is GSM. Cingular and AT&T are currently migrating from TDMA to GSM, I recommend avoiding them in their TDMA markets. (I sell these things, all carriers in the Philadelphia market, where both are currently TDMA, but AT&T migrates next month)

    Nextel uses iDEN, standing alone. Good digital voice service, minimal data capabilities right now, but coverage density on par with the others. (mid-atlantic area, at least)

    AMPS towers are no longer being maintained/built TTBOMK, but they still provide considerably more coverage geographically in the eastern US (don't know elsewhere) than any of the digital services.

    If you can find a GSM/AMPS handset (and a carrier that will support both, or just GSM and emergency use on AMPS) then you will probably be well served. Otherwise look to Verizon's CDMA/AMPS network. Sprint has similar coverage, on a different frequency from Verizon [of course!] but their customer service and support practices are atrocious. (Like often $3 per customer service call, and shutting off service 2-3 days after activation!) If passing a credit check is a problem, see Sprint, otherwise move on.

    If multinational roaming is in the cards, GSM is probably the only contender, (check gsmworld.com [gsmworld.com] for lots of info) and more than half of the current T-Mobile handsets handle it. (3 motorola, 2 samsung)

    j

  • ... one of these [thuraya.com]. GSM roaming where it's available, satellite where it's not.
  • I work for a cellular equipment company [sonyericsson.com]. To help get our newbies/co-ops/etc up to speed, I put together a brief explanation of the standards and how they evolved into the current mess. You can read it here [kr4jb.net].

    By the way, my company made one GSM1900/AMPS850 phone, the CF888. From what I can tell, it did not sell very well, and operator support was a little sketchy (there are a lot technical details to get inter-network roaming to work properly).
  • My ancient analog phone gets a signal in all but the most remote of areas
    Welcome to Kansas, chump.

  • Try GAIT phones. They are phones that support GSM + TDMA (and therefore AMPS also). What GSM/TDMA frequencies they support depends on model.

    GAIT phones were created so that Cingular and AT&T have a smoother migration path to GSM/GPRS for their TDMA markets.

    Here are a few GAIT phones I know of:

    FYI, here in the US we use GSM1900, TDMA800 and TDMA1900. TDMA isn't widely used outside of North America bcause TMDA800 is basically Digital AMPS. Hence most TDMA phones should support AMPS also.

    The rest of the world use GSM900 and GSM1800. There soon will be GSM850 available globally, which allow GSM850-compatible phones be used worldwide. Though I'm not sure if a GSM800(US) or GSM900(non-US) phone can use the GSM850 band.

    • One more thing about the phones I mentioned:

      They all support AMPS, TDMA800/1900 and GSM900/1800/1900. So they can be used just about anywhere in the world with a cell signal.

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