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The US is the only country with CDMA phones. ROW uses sim based GSM phones.

You might wanna tell that to the countries on this list. Or are they all owned by the US?

CDMA requires accurate time synchronization among all base stations and mobile stations. The accuracy must be within a few microseconds among base stations because the pilot code phase is used to distinguish them. When a mobile station is communicating with a base station they must be synchronized to within a fraction of a chip (814 ns). And the "clocks" (the PN generators) that must be synchronized have a period of 37 centuries...System time is referenced to Global Positioning System (GPS) time.

- cdg.org

Yes, cell sites did have GPS timing receivers prior to E911 location requirements. E911 location wasn't even a requirement until the end of 1995, and aging GPS timing receivers from cell sites were present on the surplus market years before that.

Finally, you're unsuccessfully arguing against a single point in my original post, and there were four, any/all of which falsify your original argument, not that it takes much to find completely incorrect statements in what you post.

Perhaps they are implementing this? http://www.cdg.org/news/press/2009/Aug17_09.asp

A complementary device enhancement known as simultaneous 1X Voice and EV-DO Data (SVDO) will also become available during the same timeframe and will enable CDMA2000 devices to access EV-DO packet data services while in an active 1X circuit-switch voice call.

So that is a simple upgrade then? Is it backwards compatible with existing devices? If you are going to upgrade every tower anyway, why not go with HSPA+/HSUPA and get near LTE speeds right now and be able to support the iPhone 4 and other existing handsets?

A complementary device enhancement known as simultaneous 1X Voice and EV-DO Data (SVDO) will also become available during the same timeframe and will enable CDMA2000 devices to access EV-DO packet data services while in an active 1X circuit-switch voice call.

Most of those place listed were some little island in the middle of nowhere

So Canada, Mexico, India, Brazil and China are little islands in the middle of nowhere, huh? My goodness, you are one dense individual. Why don't you take a look around and realize that despite what you seem to think, the world does not revolve around Europe. Honestly, we Americans tend to be horrible about thinking about things through our perspectives only, but you're definitely giving us a run for our money.

If you think anyone in Europe is seriously going to roll out a CDMA network I have a nice bridge to sell you.

CDMA is already there, dude. Maybe not in your neighborhood, but don't act like it doesn't exist.

To travel internationally you only need GSM. It is only the US that has the CDMA standard.

Not true. CDMA is available worldwide - pretty much everywhere except Central America, western Europe, and Australia.

In fact, there are more CDMA subscribers in Asia than North America. There's no GSM in Japan, but there is CDMA.

did you know that GSM is used in every market in the world, and CDMA is only used in the US?

OR... MAybe I HAVE a CDMA phone and can actually check these things? At the very least you could do a quick check of the capabilities of your own country.

iCell is already used in the cellphone industry. Though most cellphone users don't know this. It has been used for years, by Telos Technologies (bought by UTStarcom), for the IP base stations. Most specifically the All-IP CDMA base stations.

Though not exactly the same, I think there will be trade mark problems.

UTStar iCell: IP Based cellular base station system
Apple iCell: iPod cellular phone

And you know how sensitive people are to trademarks these days, especially across industries.

For those interested in what an IP base station is, and how it relates to traditional base stations have a look at a presentation (pdf) done by Jack Marr about All-IP CDMA infrastructure, it has some nice differences between traditional infrastructure and All-IP infrastructrue.

The link you provide (CDMA site) while a useful list of CDMA-2000 operators, it is not at all the same as the list of 2G CDMA operators (which is less extensive).

And while you find GSM networks in almost all countries which have CDMA or CDMA2000 (e.g. in the US it is now about 50%-50%), the opposite is by far not true. Both by coverage, by countries and by number of users, GSM is the standard (e.g. over 1000M GSM vs. 226M CDMA)

Even where CDMA operators exist, you can't bring your phone to one of those countries and swap a SIM, because there is no SIM... you need a new phone anyway to use their service at local rates (while any unlocked GSM phone can accept a SIM from any GSM operator in the world).

Finally, GSM is vendor-independent - not tied to a single company like CDMA with Qualcomm...

The link you provide (CDMA site) while a useful list of CDMA-2000 operators, it is not at all the same as the list of 2G CDMA operators (which is less extensive).

And while you find GSM networks in almost all countries which have CDMA or CDMA2000 (e.g. in the US it is now about 50%-50%), the opposite is by far not true. Both by coverage, by countries and by number of users, GSM is the standard (e.g. over 1000M GSM vs. 226M CDMA)

Even where CDMA operators exist, you can't bring your phone to one of those countries and swap a SIM, because there is no SIM... you need a new phone anyway to use their service at local rates (while any unlocked GSM phone can accept a SIM from any GSM operator in the world).

Finally, GSM is vendor-independent - not tied to a single company like CDMA with Qualcomm...

The link you provide (CDMA site) while a useful list of CDMA-2000 operators, it is not at all the same as the list of 2G CDMA operators (which is less extensive).

And while you find GSM networks in almost all countries which have CDMA or CDMA2000 (e.g. in the US it is now about 50%-50%), the opposite is by far not true. Both by coverage, by countries and by number of users, GSM is the standard (e.g. over 1000M GSM vs. 226M CDMA)

Even where CDMA operators exist, you can't bring your phone to one of those countries and swap a SIM, because there is no SIM... you need a new phone anyway to use their service at local rates (while any unlocked GSM phone can accept a SIM from any GSM operator in the world).

Finally, GSM is vendor-independent - not tied to a single company like CDMA with Qualcomm...

Try that with a CDMA or iDEN phone...

Check out the Samsung i790. It's a combination CDMA/GSM phone. You can pretty much use it anywhere they use CDMA (South Korea, Canada, US, parts of China, Taiwan, Thailand, Israel, Australia, New Zealand, Japan, India....there's a lot of them), then you can use in GSM mode in all the other countries. Pretty cool.

Europe uses GSM and now UMTS, and there's no option to use something better, because GSM/UMTS is The Law.

Oh fuck. I better tell all these providers that GSM/UMTS is the law. Especially Portugal.

Or how about Sweden launching rural 3G in Sweden and Norway using 450MHz CDMA. Shit. I better ring them too. That was close!

Sorry, the US isn't the only one using TDMA/CDMA. In fact, over 202 million people use it worldwide, with over 120 million outside the US.

GSM has about 1 billion subscribers.

Um, in the US as a whole, the CDMA (Sprint/VZW) network is far superior to the GSM networks--and that includes both CingulATT and T-Mobile. Everyone I know agrees. My roommate got an ATT phone--and requested specifically the older TDMA technology just to avoid the GSM hell we have here.

Another example of this smart decision--another US TDMA provider, US Cellular, is transitioning its subscribers not to GSM, but to CDMA, after having considered all options. Who gives a shit if you can use the latest stupid-ass Sony-Ericsson phone if your service is so bad half your calls are dropped and the rest, nobody can hear you?

I'll take CDMA and no Bluetooth support over the pathetic US GSM network any day. And by the way, the whole world most certainly has not standardized on GSM technology. Far from it. Over 188 million subscribers worldwide rely on CDMA.

Just because large portions of Europe use GSM only doesn't make CDMA any more proprietary. What's wrong with competition in the marketplace? When several vendors join forces to cooperate on one network, we get what happened after the T-Mobile/Cingular accords in 2001--the companies cram twice the subscribers onto one network while investing no more resources in network infrastructure. This results in a shitty, unreliable network. But with competing standards, each companies has to keep up its network or die. I'd say that's preferable. Who cares if phones are portable between networks? The contracts keep you in one place for a year or two anyway, and by the time the contract is up you can buy a comparable replacement phone that works on the other network for $40 on eBay. Big deal.

At first, it seems that the solution portrayed in the article would make the deployment of GSM networks easier and cheaper. This would not only be a solution for developing countries, but also for rural areas in western countries. An illustration of this last point is readily made by comparing the GSM coverage of a densely populated country like The Netherlands (former state provider KPN) to that of a much more sparsely populated country like the US (AT&T wireless).

However, GSM is not the only cell-phone standard there is. Another standard which is often used in rural areas is CDMA. It seems this standard features larger cells, and fewer base stations (for, of course, a less densely populated cell). Indeed, Verizon has plans to convert parts of its network to CDMA: see here.

Does anybody have altual experience with deploying CDMA networks? (obviously, given the coverage map for GSM, I don't need that experience in Holland ;)

The whole point of GPRS is that you pay for the traffic you use (rather than connect time)...

Here's a little background for people in GSM-only land. Outside the U.S. In the U.S., providers refused to standardize their technology, claiming that GSM wasted too much bandwidth. If I remember correctly, CDMA is the leading technology, with TDMA second, and various forms of GSM (not all of them compatibile with international GSM systems) a distant third.

and here - for a CDMA FAQ

and here for why CDMA is better than analog along with a whole lot of other shit as to why dropped calls are far less frequent on digital networks as opposed to analog ones...

The only thing you missed is that CDMA stands for Code Division, Multiple Access not Channel Divison, Multiple Access.
CDMA also uses 1.9 GHz and GSM in Europe uses 1.8GHz.

Getting access to the carriers network isn't something the major carriers do happily. All of them salivated at the idea of providing highly accurate traffic data to both the transit authority, companies and consumers, but they couldn't stop bickering enough to move ahead. Most of the arguments where over the value of the technology, but whether they should develop it in house and who should lead the effort.

For those who want to know more about cell technology here is a slide about CDMA, which talks about GSM and TDMA. It's biasd towards CDMA, but the information is still good.

This is so true, regarding the silly european carriers choosing wcdma instead of cdma2000, which can be deployed in existing spectrum, since it only needs 1.25mhz of bandwidth. This article does not mention 1xEV-DO, which also runs in 1.25mhz of bandwidth, but delivers 2.4mbps. It is already commercially deployed in South Korea, and Verizon is trialing it in Washington D.C., and San Diego. See here for details on that. Monet Networks is also trialing 1xEV-DO.

This is so true, regarding the silly european carriers choosing wcdma instead of cdma2000, which can be deployed in existing spectrum, since it only needs 1.25mhz of bandwidth. This article does not mention 1xEV-DO, which also runs in 1.25mhz of bandwidth, but delivers 2.4mbps. It is already commercially deployed in South Korea, and Verizon is trialing it in Washington D.C., and San Diego. See here for details on that. Monet Networks is also trialing 1xEV-DO.

This is so true, regarding the silly european carriers choosing wcdma instead of cdma2000, which can be deployed in existing spectrum, since it only needs 1.25mhz of bandwidth. This article does not mention 1xEV-DO, which also runs in 1.25mhz of bandwidth, but delivers 2.4mbps. It is already commercially deployed in South Korea, and Verizon is trialing it in Washington D.C., and San Diego. See here for details on that. Monet Networks is also trialing 1xEV-DO.

There seems to be a lot of confusion running around on this issue. I would recommend looking at this whitepaper. Admittedly, it is from the CDMA development group web page, so take some of the spectral efficiency claims with a grain of salt. Still, it is a pretty good introduction, and there are some other helpful papers on the technology there.

Monet Mobile Networks provides wireless broadband in rural areas using cdma2000 1xRTT (144kbps), and is upgrading to 1xEV-DO which provides 2.4mbps downstream and 144kbps up. The already have 1xEV-DO trial network Manhattan, Kansas. Their service fee is a flat 49.95 a month, unlimited usages. They also have 1xRTT service up in Fargo, N.D., and Sioux Falls, S.D.
Here is more info on the 1xEV-DO network.

PCS is NOT a frequency variant of GSM. PCS (Personal Communication Services) is the FCC definition for digital wireless services at the 1900 MHz bandwith range. This includes CDMA, TDMA, and GSM which run in North America at 1900 MHz as opposed to 800 MHz most everywhere else.

The problem here is not Europe being technologically superior the United States, but the fact that their mobile systems run at GSM 900 and 1800 MHz. GSM in the united states is exclusively 1900 MHz.

That being said, Nokia et. al. could easily retool their 800/1800 MHz GSM phones to work at 1900 MHz, but that's just part of the problem. Nokia doesn't sell directly to the consumer, and support is left to the provider, whose customers have a tendency to be more idiotic than their european counterparts.

Providers here have a hard enough time trying to teach Sally Chatterbox and Joe AOL how to use their digital phones, and here you have the other reason why you're not likely to see these kinds of mass-marketed advanced phones here.

Hey Jage,

I think that you missed the point with this one. Qualcomm was able to get 153kbit/s with one person in a moving car. That's quite an accomplishment. This is part of their High Data Rate (HDR) portion of CDMA2000. That specification is aiming at providing 1MB/sec to a stationary person & 384 kbit/s to a walking person.

Although I don't care to start a holy war with the GSM folks (for those who don't know, the war between CDMA & GSM is almost as ferocious as Gnome vs. KDE, Macintosh vs. Windows, Ford vs. Chevy, etc), I will say that GSM will not get 144 kbit/s in the USA, because of the extremely limited bandwith provided by the FCC. Because of the way the FCC split the 800MHz band, Qualcomm was limited to design CDMA into a 1.25 MHz framework. (IMHO, the FCC did do a much better job allocating the 1900MHz (aka PCS) bandwidth, but we are still stuck with the 800MHz regulations) To get 153 kbit/s in 1.25MHz bandwith is pretty amazing, IMHO.

Maybe when the FCC auctions off the next frequency, they will take back the 800MHz frequencies and limit them to FDMA (frequency division multiple access, aka AMPS). That way, we would be able to take advantage of a wider spectrum for our data transfer.

If you want to learn more about CDMA, I recommend looking through the CDG (CDMA Development Group) website. (should I link to that, or is Judge Kaplan going to get mad =-) )

Dan