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CDMA, Cell Phone Standards And Who "Wins"

Fubar writes "Former Qualcomm engineer Steven Den Beste, Captain of the USS Clueless outlines why he thinks the US is primed to overtake Europe and Japan as the technological leader in cell phone technology. He argues it stems from open competition and the use of CDMA."

28 of 498 comments (clear)

  1. Overtake Japan? by Yosho · · Score: 3, Informative

    Uh-huh. My Japanese class just recently watched a short clip of videos from Japan. The have cell phones there with built-in cameras that you can use to see the other person you're talking to (assuming their phone supports it) or even take pictures and e-mail them.

    Not only that, it's common for high schoolers to have these kinds of phones in Japan; at least where I live in America, it's strange for high schoolers to have cell phones at all. And we're poised to overtake Japan? Suuure.

    --
    Karma: Terrifying (mostly affected by atrocities you've committed)
    1. Re:Overtake Japan? by seizer · · Score: 3, Informative

      There's at least one phone that will work in America which can do that (if the network supports picture transmission - otherwise, you could send it via email if you have GPRS).

      It's the Sony Ericsson T68i and it'll work very happily on VoiceStream, because it's a tri-band GSM phone. Aside from the camera, it also has BlueTooth, POP3, and some elite easter eggs :-)

  2. Slashdotted, of course. Here's a mirror. by Anonymous Coward · · Score: 5, Informative

    (On Screen): As I think many of my readers know, I used to work for Qualcomm designing cell phones. Qualcomm is the company which invented CDMA, and made it practical, and made it into a market success, and it now dominates the American market, where Verizon and Sprint both use it. There are two other nationwide cellular systems: AT&T currently uses IS-136 TDMA, which is obsolete and has no upgrade path. Cingular uses GSM, a more sophisticated form of TDMA from Europe.

    And right now I'm basking in the evil glow of a major case of schadenfreude.

    The original cell phones were analog, using fairly straightforward FM for voice communication. When your phone was in a call, it was granted a frequency by the cell and used it exclusively for the entire duration of the call. FM encoding is extremely inefficient in use of bandwidth, and spectrum was scarce and expensive, and it rapidly became clear that FM wasn't able to handle the traffic which was expected and which was really needed to make cellular telephony a profitable business. One obvious approach was to use digital communications, and to take advantage of advances in microprocessor and digital IC technology to compress the voice traffic going both directions, and thus you saw deployment of the first Time Division Multiple Access (TDMA) digital systems. What they do is to take a single channel and timeshare it among several phones, who digitize and compress their voice traffic and transceive it during their timeslice. With IS-136, a 30 KHz channel which had carried only one voice call with AMPS could now carry three digitized calls.

    GSM went further than that, and abandoned the old channel size entirely. It allocated 200 KHz channels and divided them into 8 slices, giving each phone somewhat less than 25 KHz effective bandwidth. (There are some losses due to time guardbands and protocol overhead.)

    GSM also included a very powerful set of features above that, and included some interesting features not directly associated with the RF link, such as a personality module which contained a customer's phone number and billing information that could be moved to another phone any time the customer wished to. (That particular featured turned out to be a decidedly mixed blessing. While that ability was very convenient for legitimate customers, it was also a magnet for thieves and frauds.)

    GSM was clearly superior to IS-136 or such abortions as IDEN (a Motorola design which never became an industry standard because Moto was never willing to license it, which meant that systems which adopted it could only get infrastructure and handsets from Motorola).

    In Europe, various governments decided that they (the Europeans) had designed the ultimate digital cellular system, and they passed laws making it illegal to deploy anything except GSM, whose primary supporters/suppliers were Nokia, Ericsson, Siemens and Alcatel.

    Meanwhile, the FCC decided that it would not mandate any industry standard. It granted licenses for spectrum but permitted the licensee to choose whatever equipment and standard it wanted. (Within limits. There were certain certification standards required by the FCC to guarantee safety and to avoid interference between neighboring systems.)

    And all through the 90's, me and everyone else in the US cell phone industry put up with constant ragging from Europeans about the evident virtues of GSM and the equally evident virtues of a government mandated standard. While in the US you had what seemed at the time to be utter chaos, with a huge number of small companies using a bewildering array of different standards, in Europe anyone could carry their phone almost anywhere in the continent, and if they couldn't use it they could move their personality module into a local phone and use that.

    Of course, that apparent chaos in the US was only a temporary phenomenon, and I think maybe the FCC and the rest of the government knew it would be. There's always shakeout, but in the meantime this kind of government policy of keeping hands off meant that the industry was given broad ability to experiment. And within that environment, early in the 1990's, the founders of my former employer Qualcomm began to work on a radically different way to handle cell phones called Code Division Multiple Access, or CDMA. It's radical in many, many ways but by far the most obvious is that all the phones in the system and all the cells in the system operate simultaneously on the same carrier frequency. They don't "take turns" because they don't need to.

    In the computer industry we talk about the "ISO seven layer model", where the process of communication is modularized and each layer uses the one below it without worrying how the lower layer actually works. TCP works whether the physical layer is 802.11b or ethernet or something else entirely, and TCP itself doesn't change based on that. TCP uses IP, and IP uses the datalink layer, and the problems of the physical layer are dealt with by the datalink layer. But if the physical layer is a 56 KBaud modem, then there are things which won't be possible, which might be possible with 100 megabit ethernet. No amount of work at higher levels can compensate for the fundamental superiority of ethernet over a telephone modem.

    Cell phone protocols do the same kind of thing. There's an RF layer and protocols above that, some of which can be very high level and quite abstract, such as the one which controls sending of text messages. However, the change from analog to TDMA was a change at the RF layer. CDMA was yet another approach to the RF layer, which was radically different again. (IS-95 is a specification for a complete protocol stack which includes CDMA as its RF layer.)

    In fact, CDMA was so revolutionary that when it was first discussed, many thought it couldn't be made to work. Indeed, at least one European company deeply involved with GSM, Ericsson, went through the three classic stages of Not Invented Here syndrome:

    1. It's impossible.
    2. It's infeasible.
    3. Actually, we thought of it first.

    When I worked for Qualcomm, I had to soft pedal this. Now I'm no longer associated with the company, and I can vent about those idiots. At first, the most vocal top brains at Ericsson tried to claim that CDMA violated information theory.

    In IS-95 CDMA, a single carrier frequency has a bandwidth of 1.2288 MHz, and up to 40 cell phones in a given sector can all be transmitting chips at that rate on the same carrier frequency, which seemed on first examination to assume that it was possible to send fifty million bits through a one-and-a-quarter MHz band, which would indeed violate Shannon. The mistake they made was that chips aren't "information" based on Shannon's definition, and though those phones were sending chips that fast, they were actually sending bits (real data) at no more than 14,400 bits per second each. (I'll try not to get too bogged down in technical details here, but to some extent it's unavoidable.)

    Unfortunately, Qualcomm did a field test in New York City where several prototype phones mounted in vans were able to operate at once on the same frequency talking to multiple cells all of which also operated on the same frequency.

    The next argument was that though it seemed technically possible, it would be too expensive. Everyone knew that the electronics required to make CDMA work was a lot more complicated than what TDMA used, and Ericsson's loud voices claimed that it could never be reduced in price enough to make it competitive. And shortly thereafter Qualcomm proved that wrong, too, by beginning to produce both infrastructure and phones at very competitive prices. (Qualcomm did this to bootstrap the industry. It's no longer in either business.)

    After which Ericsson suddenly decided that it had applicable patents and took Qualcomm to court. Over the long drawn out process of litigation, every single preliminary court judgment went in favor of Qualcomm, and it became obvious that Ericsson didn't have a case and that Qualcomm wasn't going to be intimidated. Ultimately, the entire case was settled in a massive omnibus agreement where Ericsson became the last of the large companies in the industry to license Qualcomm's patents (on the same royalty terms as everyone else) while taking a large money-losing division off Qualcomm's hands and assuming all the liabilities associated with it, and granting Qualcomm a full license for GSM technology. The industry consensus was that this represented a fullscale surrender by Ericsson.

    Nokia wasn't anything like as foolish and had licensed several years before. (Just in passing, the fools at Ericsson are in the front office. Their engineers are as good as anyone else's.)

    Still, in the years of apparent chaos in the US, when loud voices in Europe proclaimed the clear advantage of a single continental standard, order began to appear out of the chaos here. Small companies using the same standards set up roaming agreements, and then started merging into larger companies, which merged into yet larger ones. One company (Sprint) started from scratch to build nationwide coverage. Bell Atlantic Mobile acquired GTE Mobile (who had been a joint partner in PrimeCo), and eventually merged with Airtouch to form Verizon, all of which was based on IS-95 CDMA, mostly on 800 MHz. Sprint eventually implemented a reasonable nationwide system also based on CDMA. The last major nationwide system to form was Cingular, after the various GSM carriers in the US realized they were in big trouble competing against Verizon and Sprint and AT&T (which uses IS-136).

    Once the existence and commercial feasibility of CDMA were established beyond doubt, other aspects of it began to become clear. At the RF layer, CDMA was obviously drastically superior to any kind of TDMA. For one thing, in any cellular system which had three or more cells, CDMA could carry far more traffic within a given allocation of spectrum than any form of TDMA. (Depending on the physical circumstances, it's usually three times as much but it can be as much as five times.) For another, CDMA was designed from the very beginning to dynamically allocate spectrum.

    In TDMA, a given phone in a given voice call is allocated a certain fixed amount of bandwidth whether it needs it or not. In IS-136 that's a bit less than 10 KHz, in GSM it's somewhat less than 25 KHz. (Going each direction; the total is twice that.) But humans don't use bandwidth that way; when you're talking, I'm mostly listening. So your 25 KHz channel to me is carrying your voice, and my 25 KHz channel to you is carrying the sound of me listening to you silently.

    In CDMA, the amount of bandwidth that a given phone uses changes 50 times per second, and can vary over a scale of 8:1. When I'm silent, I'm only use 1/8th of the peak bandwidth I use when I'm talking. (But I don't actually send full rate most of the time even when I'm speaking.) That's very useful for voice but it's essential for data which tends to be extremely bursty, and CDMA was born able to do this. It's always had that capability. It's also always had the ability for different phones to be given different overall allocations of bandwidth, because the initial standard included both 8K and 13K codecs (which respectively use 9600 baud and 14,400 baud). So when higher data rates were desired, it was possible to augment the cell and create new cell phones which could transmit 56 kilobits per second using the same frequency as existing handsets.

    When GSM wanted to do that (send data at a rate faster than the existing voice channel supported), they ended up having to allocate an entirely new carrier just for that job, which handled nothing except data, and to deploy entirely new infrastructure for it. The resulting system is called GPRS, and in many ways it turned out to be very unsatisfactory for the operating companies because it's really expensive to deploy and because it cuts down on the bandwidth they have available for voice. A given chunk of spectrum must be permanently assigned to one or the other; it can't be reallocated dynamically. Data and voice in CDMA, on the other hand, both use the same carrier and bandwidth is reallocated between the two 50 times per second automatically, and you can implement high speed data without having to install new transmitters in all the cells.

    With the push to greater and greater data rates, everyone recognized that a new generation of cellular equipment would be needed, the legendary 3G.

    And for the reasons given above, and several others, it was equally clear that it had to use a CDMA air interface. GSM was the very best propeller-driven fighter money could buy, but CDMA was a jet engine, and ultimately TDMA could not compete. The fundamental weakness of TDMA at the RF layer could not be compensated for at any layer higher than that, no matter how well designed it was. GSM/TDMA was a dead end, and to create 3G, Europe's electronics companies were going to have to swallow their pride and admit that Qualcomm had been right all along.

    This article in the Economist says that it's not going well. When Qualcomm and its partners designed a new 3G system with new capabilities, they were able to make it backward compatible with IS-95. The new standard is called CDMA 2000, and a CDMA2K handset can work with IS-95 infrastructure, and an IS-95 handset can work with CDMA2K infrastructure, and CDMA2K cells can sit next to IS-95 cells and use the same frequencies. Thus existing operating companies using IS-95 can upgrade incrementally replacing individual cells as budget allows and selling new handsets without having to wholesale replace all existing ones at once. Most important of all, it means that you can take an existing system using an existing spectrum license, and phase it over without acquiring any new spectrum.

    None of that is true for GSM. CDMA and TDMA are fundamentally incompatible and there's no way to create a new system (which they're calling WCDMA) which can support existing TDMA handsets. It's technically impossible for the new standard to be backward compatible. Worse is that there's no easy way to phase existing spectrum over. In practice, when WCDMA appears, existing GSM systems will have to install it all, issue new handsets to all customers, and then one day throw a switch -- or else they'll have to license new spectrum for WCDMA while continuing to run GSM on the existing spectrum for legacy customers. It's all going to be very ugly when it happens. (Note: It is possible to design new WCDMA handsets so that they are capable of working with old GSM/TDMA infrastructure, but it adds substantially to the cost of the unit. It is not possible at all to make WCDMA infrastructure work with GSM/TDMA handsets.)

    If it happens, for the other thing they're discovering over across the pond is that making CDMA work is a lot harder than they thought it was. They're having technical problems. This article talks about the experience that DoVoMo had in Japan when it deployed the first WCDMA system in the world. It doesn't mention that DoCoMo has had to recall and replace thousands of handsets at its own expense when it was discovered that the handsets had fatal technical problems which could not be fixed. (In fact, DoCoMo had to do this twice. Both times were fantastically expensive, and both times represented really bad public relations fiascos. DoCoMo's name is mud in Japan now; they may never fully recover.)

    CDMA2K, on the other hand, is real and it works now. Commercial shipments of infrastructure and handsets began a long time ago. Both Sprint and Verizon began their conversion process more than a year ago, and it's been deployed elsewhere in the world (such a by DoCoMo's rival KDDI) and what everyone is discovering is that it works. The transition is clean. There haven't been any unfortunate surprises.

    And it works pretty damned well. (In Japan, half the handsets have cameras in them and their users send each other pictures.)

    On the other hand, in Europe the service providers are in deep trouble. They spent truly vast amounts of money on licenses for new spectrum which they can't actually use yet. The licenses specify that they can only be used for WCDMA, and none of the equipment suppliers are actually ready for deployment. Some of the operating companies are talking about giving the licenses back.

    And others are beginning to ask if they can have permission to deploy CDMA2K instead, but the bureaucrats in the EU aren't having any of it. Yet.

    I confess to a deep feeling of satisfaction about this on a personal level, primarily because of all the horseshit I put up with from GSM fans over the years when they talked about how superior the European approach to this was.

    The thing is that if the US had followed the same policy, CDMA would never have been given the chance to prove itself. We now have just as good of nationwide systems and just as much portability as the Europeans do, only our system is fundamentally better. GSM has many features which are marvelous, but they can eventually be grafted onto IS-95 and CDMA2K, because they're all implemented at high protocol levels or don't have anything to do with the RF link. IS-95 and CDMA2K have many cool features, too, but it isn't possible to implement them on a TDMA air interface, so the only way that GSM can have those features is to toss TDMA and switch, which is what they're now trying to do.

    So I'm sitting here basking in the warm glow of schadenfreude because nemesis has caught up with European hubris in the cell phone industry.

    But there's more to this, because in the microscopic this turns out to be a morality tale which more broadly shows the difference in approaches to most things between the Europeans and the Americans, and I think demonstrates quite clearly why our way is more successful.

    Though the adoption of a continent-wide standard for Europe in the 1990's did have certain benefits, it also had some hidden prices. It gave them compatibility, but it was also protectionism, and as is always the case with industries shielded by protectionism, the European cell phone companies became arrogant and complacent, and as a result they fell badly behind. Now they're trying to catch up, and it isn't turning out to be easy. They licensed Qualcomm's patents, but what they're now discovering is that Qualcomm didn't patent everything it knows about making CDMA work, and that it's a really difficult problem. (Damned straight it is. We know a hell of a lot we're not telling. It's pretty straightforward to make it work badly and unreliably, using a lot of battery power. Making it work well on low power is damned tough, and that knowledge is not for sale.)

    Part of their problem is that they're trying to run before they've learned to walk. Qualcomm and its partners are moving to CDMA2K after many years of working with IS-95, but the GSM coalition is jumping straight into WCDMA cold.

    Like all protected industries, the GSM companies didn't make the investment they should have early enough. Part of why they're way behind is that they started late, and much of that was because of ego, because they didn't want to admit that Qualcomm had been right (or to pay Qualcomm royalties). So they lost two full years in lawsuits and negotiations with Qualcomm before the real design process could begin. And then they discovered that the problem was harder than it looked. As it now stands, it's going to be an interesting question to see whether they can ever get it to work (especially to get interoperability), and more importantly, even if they do to see whether they will be too late and will have missed the market window. I think they will make it work, but I think it will be too late.

    Here are some of the lessons I see in this.

    First, Europe pulled this decision up to as high a level as it could. When the legal mandate to use GSM was passed, the EU didn't yet exist. Individual nations each passed such laws based on a consensus. In the US, that decision was pushed down as far as possible, and the superiority of CDMA over any TDMA-based system was decided by millions of cell phone users who voted with their wallets.

    Second, Europe tried to stop the clock. It decided that it had the final answer with GSM and that no further experimentation was necessary because no further improvement was possible. In the US, the government kept its hands off, and in fact if another newer system comes along which is superior to CDMA, it will have the same opportunity commercially that CDMA had. (Not quite; the market has evolved and we're into the "standardization and shakeout" phase now. But there won't be any government mandate preventing it.)

    Europe emphasized cooperation over competition, consensus and agreement over "let's try it and see what happens". It was viewed as important that there be compatibility over the whole continent, and to achieve that they outlawed competition. In the US, we valued competition, and ironically we not only ended up with compatibility over the whole continent but got that compatibility with a superior system which emerged out of competition.

    Despite claims to the contrary, Europe passed those laws in part precisely because the standard which was being protected was European and most of the equipment which would be used was homegrown. Part of why those laws were passed was to lock out the US. (Some American companies made GSM equipment, but they never had much market share in Europe.) In the US, everyone was free to compete, and for quite a while the largest seller of handsets here was Nokia. GSM was deployed here and attempted to compete against CDMA on a level playing field, and got handed its ass.

    GSM fans will point out that GSM is more broadly deployed elsewhere in the world than IS-95. They'll be careful not to point out the extent to which bribery played a role in that. (Things like "If you choose GSM over CDMA, we'll build a factory there" which is how GSM mostly won in Brazil.)

    But that kind of thing is ultimately self-defeating, and TDMA/GSM isn't going to be competitive against CDMA2K, and the Europeans can't make WCDMA work reliably. And as a result of that, a lot of the cellular telecom companies in Europe are in deep financial trouble, not to mention facing legal deadlines for deployment of 3G which cannot possibly be met. MobilCom in Germany is near death, for example, and just announced that it would lay off 40% of its staff. Apparently it would already be dead were it not for a 400 million loan from the German government, which has angered the EU. And because the telecom companies in Europe are all so heavily cross invested, this is a cascading problem. Part of why Mobilcom is in trouble is because France Telecom SA is in trouble and had to renege on an investment commitment. You're eventually going to see a chain-reaction sequence of commercial failures as the money runs out, or more likely you'll see huge government subsidies.

    Both these articles say that CDMA2K is "controlled by Qualcomm". That's true and not true. There's an industry standards body, and Qualcomm is probably the most important and influential member of it. It's also true that most of the CDMA2K proposal came out of Qualcomm. But the members of that standards body understand that they're going to get further by cooperation than by competition, and there's very much a "can do" attitude there which helped get a standard approved a long time ago. Qualcomm's proposal wasn't predatory. (By comparison, Sun's Java standards have been predatory, because part of the goal is to keep Sun the largest player in the Java business. Qualcomm is not the largest player in CDMA and probably never will be.) There's also heavy emphasis on interoperability and testing and standards compliance, and there is an independent testing laboratory, which even Qualcomm uses to verify its own products.

    Another of the ironies in this is that "cooperative" Europe has turned out not to be cooperating as well as "competitive America". The companies involved in the CDMA2K process are cooperating closely because it's in their own best interest to do so, not because of some sort of fuzzy philosophy of "cooperation and centralization are good things". The companies in the CDMA2K process are cooperating because they know they'll be killed if they don't, not to mention the fact that they smell GSM's blood.

    This kind of thing has played out much the same way hundreds of times before between Europe and the US, and nearly always it's had the same result. And as Europe increasingly centralizes and "harmonizes" and moves more and more authority to Brussels, it's going to keep happening. Decisions will be made from the center, and a lot of the time they'll be made wrongly because the "center" is not the infinite repository of all wisdom. The "center" chose GSM/TDMA to be the winner; America decided to let the market figure out the winner, and it didn't turn out to be GSM/TDMA.

    European centralization turned out to be a competitive advantage - for the US. And that's going to keep happening. If I was vicious and wanted to wish failure and misery on Europe, I could think of nothing better to inflict it than the process going on now whereby more and more authority will move to Brussels to be used by unelected bureaucrats who answer to no one.

    Update 20021006: Michael Jennings offers his perspective. He was involved in the cellular industry in Australia and saw the same GSM arrogance I put up with.

    Update: Though the EU didn't exist then, the GSM mandate came from the EC rather than being passed by individual nations.

    1. Re:Slashdotted, of course. Here's a mirror. by CaptainAlbert · · Score: 4, Informative

      > CDMA was so revolutionary that when it was first discussed, many thought it couldn't be made to work.

      I have to take issue with this, as it's clearly nonsense. Multi-user spread-spectrum radio communications have been in use for over fifty years by the military. The technology is so basic they've been teach the principles to undergraduates for at least ten years.

      Anyone who did express that kind of scepticism would surely have been laughed out the door.

      Grrr misinformation grr!

      --
      These sigs are more interesting tha
    2. Re:Slashdotted, of course. Here's a mirror. by Anonymous Coward · · Score: 1, Informative

      That's not entirely correct. "Spread spectrum" is simply spreading a signal across a section of bandwidth much larger than the required bandwidth necessary for the desired data speed. There are basically two forms of spread spectrum: frequency hopping and code-division multiplex. The military has used synchronized, ultra fast freqency hopping technology together with encryption to provide very secure communications for years. The Qualcomm brand of spread spectrum does not use frequency hopping. Rather it uses code divisible encoding that effectively spreads a 14.4kbps link over a bandwidth of 1.288Mcps (mega chips per sec). Each radios uses the entire bandwidth and they are distinguishible by a beautiful mathmatical encoding scheme. Designing transceivers that meet the very strict synchronization and power-balancing requirements is extremely difficult because one bad radio degrades the entire system. The code divisible form of multiuser spread spectrum was not developed into a large-scale working product prior to the 80s.

  3. Oh, I forgot.... by Anonymous Coward · · Score: 1, Informative

    To include the link to the Economist article he references:

    http://www.economist.com/business/displayStory.cfm ?story_id=1353050

  4. Re:Den Beste is an American bigot. by YeeHaW_Jelte · · Score: 3, Informative

    For the factually obsessed:
    It wasn't actually Schröder making the comparison, but the minister of Justice of his cabinet.

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    ---
    "The chances of a demonic possession spreading are remote -- relax."
  5. Re:Readable summary by kuiken · · Score: 3, Informative

    Couple that with European governments kneecapping their operators with insane 3G license fees
    The 3G was auctioned by the gov's, telco's have nobody to blame for those insane prices but themself

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  6. GSM is technically superior by igotmybfg · · Score: 4, Informative
    GSM is technically superior for two reasons. The first is that it is modular. You can stick a SIM card in anything that has a GSM slot - your mobile phone, your PDA, your laptop, your anything, and then that device becomes your communication tool, with your address book and account information. If you want, you can even copy your SIM card, so that you can have two or more devices sharing the same account information - I did this for my Dad so he could use the same account for his mobile phone and the phone we put in his car. GSM's modularity is also nice in that when your current phone breaks, you can take it into the repair shop, and they'll lend you a replacement phone. If you used CDMA you wouldn't be able to use the replacement phone without calling the mobile company and going through loads of red tape. If you use GSM, you just stick in your SIM card, and that's the end of it. Likewise, buying new phones is just as painless. In most countries in Europe you just walk into a store and buy a new phone - the mobile company isn't involved at all. The second reason GSM is superior is that the entire world uses it, outside of the USA and parts of Korea. If you get a triple band phone, you can use it here in the US as well as in Europe and Asia just by switching out SIM cards. This is what I do with my Ericsson T68.

    Incidentally, as far as I know, only providers that use GSM (in the US, Voicestream/Deutsche Telekom) offer prepaid accounts - like a debit card, you load them up with credit. This has two advantages: 1) You can't run up a huge phone bill, because after you run out of credit no outgoing calls are allowed (with the exception of emergency calls) until you buy more credit, and 2) the mobile company has no information about who you are. Because you buy the SIM card in a brick and mortar store, you can pay for it in cash and the mobile company will never know who you are. Just food for thought.

  7. GSM, UMTS, WCDMA, etc... by jrmbadger · · Score: 4, Informative

    Some people here have been getting confused about some things so let me clarify: There is a difference between discussing a SYSTEM (GSM, UMTS, CDMA 1x, CDMA2000, Iden) and discussing it's RADIO ACCESS METHOD (TDMA, CDMA, W-CDMA). For the record: GSM: Uses the TDMA Radio Access Method. UMTS: Uses the WCDMA radio Access Method. CDMA: obviously uses CDMA radio access method. A previous poster did a good job of clarifying how the different Radio Access methods work so I won't get into it. The main differences between the different systems that use the same Radio Access Method (Umts and Cdma 2000) is architecture -- that is, how the system is structured and built, as well as the messanging that goes on to bring up and support a call. So in talking about how "good" one system is vs. another, it really does no good to compare say CDMA2000 to UMTS. YES there will be some significant differences between the systems, but not in the way the information is sent on the air. If you want to talk about differences, talk about other things other than the Radio Access method.

  8. -1 Clueless Troll by Andy+Dodd · · Score: 3, Informative

    UMTS uses CDMA at the RF layer

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    retrorocket.o not found, launch anyway?
  9. Re:Den Beste is an American bigot. by Gerein · · Score: 4, Informative
    His recent blahblah parade about Schröder's comparison of Bush to Hitler (the comparison is fair and valid to anyone who has studied the rise of the 3rd Reich) reveals a "Patriot" who just doesn't get it.

    AARGH!! This story is getting worse everytime it's being told!

    First: It wasn't Schröder who did this, but one of his ministers in a unimportant election speech in some small town!
    Second: She didn't compare GWB and Hitler either, but just happened to mention both names within one sentence without any direct comparision!!

    I recently was in Taiwan and even there I saw this story on the front page of the newspaper. People, move on. Nothing to see here. The whole thing is not true and has been dramatically overblown by the media!

    Sorry for being OT, but this whole story makes me angry...

  10. Re:A Brit asks ... by Mr_Silver · · Score: 3, Informative
    Why do you have to pay BT for "metered" local calls? (In the US local calls are basically a flat fee for essentially unlimited local service.)

    It's true that with the bog standard BT package local calls are metered. This is pretty good for people who barely use the phone and hence make very few local calls.

    However there are various packages which will give you unmetered dial-up, local and/or national calls:

    From their site:

    • BT Together [£11.50] per month
    • BT Together with unlimited Local calls [£14.50] per month
    • BT Together with unlimited UK calls [£18.50] per month
    • BT Together with unlimited surf calls [£15.50] per month plus ISP charges
    • BT Together with unlimited Local & surf calls [£20.50] per month plus ISP charges
    • BT Together with unlimited UK & surf calls [£24.50] per month plus ISP charges

    It's not perfect and probably by no means near what the US has, but it's a start. I live in a shared house and my calls come to about £5 a month which means that it's not worth me paying the flat rate as I'd end up losing money.

    Mind you, BT have always been renown for dragging their heels when it comes to giving the consumer a better deal ... just look at our broadband prices and subsequent low adoption :o(

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  11. UMTS = CDMA by Andy+Dodd · · Score: 4, Informative

    Or more specifically, W-CDMA. CDMA has won at the RF later.

    That said, if you read his article, CDMA2000 (The "next generation" after IS-95 CDMA) is Here Now while UMTS equipment isn't here yet in a working form. W-CDMA has proven to be an embarassment for those providers that have rolled it out, and those that haven't are begging to use CDMA2000 instead of W-CDMA, and when the politicians say no, you see the multibillion dollar spectrum writeoffs you've been seeing right and left in Europe.

    If UMTS is so much better than CDMA2000, then why have there been so many spectrum writeoffs in Europe, while you don't hear about Verizon or Sprint writing off massive amounts of spectrum?

    --
    retrorocket.o not found, launch anyway?
  12. Re:Minnow says "Hey we will win" by Yokaze · · Score: 4, Informative
    >The phrase "widely optimistic" comes to mind.

    "Biased" is another word. Or maybe "rant".

    On the RF-level, he raves about the advantages of CDMA over TDMA, without mentioning any deficiencies of CDMA.
    Granted CDMA has a higher capacity.
    But he fails to mention breathing cells.

    Criticising Ericsson with the words:

    [...]Ericsson, went through the three classic stages of Not Invented Here syndrome:
    1. It's impossible.
    2. It's infeasible.
    3. Actually, we thought of it first.

    and later stating

    CDMA and TDMA are fundamentally incompatible and there's no way to create a new system (which they're calling WCDMA) which can support existing TDMA handsets. It's technically impossible for the new standard to be backward compatible.

    Sounds like phase 1 of NIH.
    Having a look at UMTS World and a look at the news on the frontpage (emphasis mine):

    [...]
    BLUETOOTH WCDMA CALL: Qualcomm announces worldâ(TM)s first Bluetooth WCDMA (UMTS) and GSM Voice Calls. [...]. (1/10/02)
    [...]
    GSM - WCDMA HANDOVERS: Ericsson announces the first live, dual mode WCDMA/GSM calls with seamless handover between the two modes.
    [...]

    Later, he is admitting it is possible on the mobile, but not feaseable. (NIH Phase 2). But impracticable on the infrastructure. You have to install a new one.
    Partially, correct. There have to be installed new Base Tranciever Stations. But hardly a new complete infrastructure. The whole GSM "back-end" is compatible.

    In what way is that more inpracticable than installing a new "back-end" for the higher level functions? Which he says, can easily added to CDMA2k.

    Lastly, which users are looking at the baseband-specification, when buying a mobile?
    The reason for the advantage of Japan and Europe is at a higher level. Availability and acceptance of services. Ease of use.
    --
    "Between strong and weak, between rich and poor [...], it is freedom which oppresses and the law which sets free"
  13. CDMA vs GSM by tree_frog · · Score: 5, Informative

    BIAS NOTE: I work for a major telecoms manufacturer on UMTS (the technical name for 3G - a W-CDMA technology).

    This is an interesting commentary, but it fails to note many things.

    First, the continent-wide adoption of GSM in Europe has led to huge take up of mobile phones. Everyone (schoolkids upwards) has one, communications across networks are not a problem (and are cheap), moving across national boundaries are not a problem (hell - I closed a deal on buying a house (in the UK) over the phone while crossing the border between France and Spain). There are various economic effects going on in Europe which make GSM a winner - the huge take-up, the ease of interconnection, SMS, etc.

    That is not to say that GSM does not have problems. There are certainly capacity problems in many European cities - the operators are running out of bandwidth, and this is one of the drivers for the adoption of 3G. Certainly CDMA technology offers much high capacity than GSM. GPRS does offer adequate data rates for must currently conceivable apps, but doesn't do anything for the bandwidth problem. Of course, it's also possible that GSM/GPRS is the way forwards - especially if it will interwork with 802.11 a/b for high speed data in built up areas.

    Oh, and did I mention that UMTS and CDMA (IIRC) are both frequency (rather than time) split between the uplink and downlink. This is fine for voice, but when you start running lots of hugely asymetric services (like web browsing), it doen't look so smart.

    It is probably a bit disingenuous to claim that the Europeans can't make UMTS work. The system is just going into deployment now. All the major telco manufactureres have systems out on test, and not only are they testing their own kit, they are testing interoperability of parts of the system that are being built from rival vendors kit. So, for example the Radio Access Network might come from the people I work for, but the core comes from someone else. And they are making it work with 5 nines reliability. It will arrive, and soon.

    The main problem, and one that is touched on in the article, is actually the huge take-up of GSM. The problem is that everyone who has a 3G phone is quite happy with it. Sure, new things come along all the while (e.g. picture messaging), but no-one has yet come up with a really good reason why you might want to trade in your GSM phone for a 3G one (what do you need up to 2Mb/s for on a phone??).The operators have a good reason for you to switch - they're running out of bandwidth - but that is their problem, not the users.

    Probably, what will happen is that the new 3G phones will be dual system GSM/UMTS phones. Pure GSM will gradually be phased out, but will probably always remain in remoter areas where the arguments for 3G just don't stand up economically. The handover between the GSM and UMTS systems is quite nightmareish, but their are a lot of people wrking on it at present.

    A big question is the business economics. Nokia are very strong in handsets, and they have a few UMTS contacts. Ericsson have the lion's share of UMTS contracts, but can't get the kit out of the door quick enough. Motorola doesn't have enough contracts, but may be heavyweight enough to survive to the next round, where the quality of competing products may count more. Most of the rest are dead in the water. Alcatel, Lucent, Siemens, Nortel. would you honestly count on any of them being around in a year or so?

    Hold on, it's going to be bumpy, but I think UMTS will arrive. CDMA won't disappear, but it won't go global. And the major problem that the US telcos have is their pricing models. There is more to a succesful business than technology - you have to have a product that people want.

    regards, treefrog

  14. One little correction by Andy+Dodd · · Score: 3, Informative

    UMTS (the broken piece of crap you refer to) is W-CDMA, not TDMA.

    It's still, as you say, horribly broken at the moment.

    --
    retrorocket.o not found, launch anyway?
  15. Re:Yeah, like sure by Earlybird · · Score: 3, Informative
    • It seems to me that Steven Den Beste is comparing Europe's old standard (GSM) with America new-to-be standard CDMA.
    He is comparing the currently deployed US standard (CDMA) with the currently deployed European standard (GSM/GPRS). Seems fair to me.
    • Why doesn't he compare it with UTMS, which is in all probability going to be the new standard in Europe?
    First of all, it is called UMTS (Universal Mobile Telephone Service), aka IMT-2000, aka "3G".

    Secondly, UMTS isn't really available yet. There are no public carriers, nor any consumer phones on the market. For the man on the street, UMTS for all intents and purposes does not exist. It would be an apples-to-oranges comparison.

    UMTS is actually a next-generation replacement for both GSM and CDMA. It is really a "family" of standards revolving around a set of evolutionary upgrades to CDMA called W-CDMA (Wideband Code Division Multiple Access) and TD-CDMA (Time-Division CDMA, which combines code division and time division). UTMS is designed to be able to offer both modes simultaneously.

    UMTS is being rolled out in both Europe and the US, though slowly.

  16. GSM is a not an encoding method by Midnight+Thunder · · Score: 5, Informative

    CDMA is a method of transmission, GSM is not. GSM is a collection of technologies for communication, of which transmission method is one of them. If GSM decided to include CDMA into GSM it would be possible, but it would not necessarily use the same data format across those frequences, nor the same frequency band. To find out more, see the GSM Technologies page.

    --
    Jumpstart the tartan drive.
  17. Re:It costs the cellcompany the same amount of mon by Mr_Silver · · Score: 3, Informative
    What happens in England if a land line person calls a cell phone? Do they have to pay for the cell phone charges?

    BT generally tends to charge roughly the same sort of price to call each of the mobile networks. This price is higher than the local/national calls. The advantage we have is that all mobile/personal numbers start with 07. So if you give me 07123 456789 I know how much it's going to cost me before I call.

    If I am on T-Mobile and I phone Vodafone then it'll cost me about 48 pence per minute (as it's cross network). Vodafone gets nothing as it's the receiving party. If I call my own network then it costs very little.

    In the UK, the operators don't charge you for the receiving bandwidth, just the outgoing one. Therefore it is up to them to make it so that their customers call people as much as possible to get their revenue, rather than encouraging other people to call them (it's much easier to incentivise someone to call people on their mobile than it is to say, "hey, get your friends to phone you more!").

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  18. Re:Europe has aging infrastructure by Yokaze · · Score: 2, Informative

    From the CIA World Factbook:
    [...] Germany has one of the world's most technologically advanced telecommunications systems [...] connected by modern networks of fiber-optic cable,[...]
    France: highly developed [...] extensive cable and microwave radio relay; extensive introduction of fiber-optic cable;
    Italy: modern, well developed, fast; fully automated telephone, telex, and data services

    Actually, the reverse could true. In standardising the various froms of DSL, special respect to the US situation had to be paid. Only two wires, high impedance. A professor of mine (lived in Germany/Sweden) called them "Klingeldraehte", which means they are usually used for a doorbell.

    In my experience, the US is highly diverse. Including the infrastructure. In some regions, you have a top-notch infrastructure some people only can dream of (highways, public transport, telephone), in others you're better of with a pidgeon and a mule.

    The higher influence of the state controlled monopolistic telcos lead to an almost equal level of quality (not to mention the equally high costs)

    > This is why Europe pushed so hard at establishing the GSM standard for the continent.

    Actually, before having GSM, each country in Europe had it's own analog network. They became aware of the various disadvantages of this approach and started almost at the same time with the developement of GSM.
    In 1982 the Group Spécial Mobil was founded.

    The first commercial analog cellular based on AMPS was introduced in 1983 (Japan 1979, Nordic Europe 1981)

    --
    "Between strong and weak, between rich and poor [...], it is freedom which oppresses and the law which sets free"
  19. Re:It costs the cellcompany the same amount of mon by POPE+Mad+Mitch · · Score: 2, Informative
    What happens in England if a land line person calls a cell phone? Do they have to pay for the cell phone charges?
    Yes, and it's easy to work out how expensive the call is going to be too.

    Mobile phones have a seperate area code to landlines, so do free phone (toll free) numbers, lo-call (charged local call rate no matter where you are), and premium rate numbers.

    So if you dial an area code starting 01xxx or 02xxx then you know its a national rate land line call. if you dial 07xxx its a mobile, 09xxx premium, etc.

    This also means that a mobile phone could be registered anywhere in the country, the first few digits of the number only tell you which telecoms provider they are with.

    The exact cost of the call to a mobile varies according to how much that mobile phone carrier, and how much the originating carrier charges. Which can vary, but not much generally. In the same way that the exact cost of a premium rate call can vary, but the area code prefix tells you the rough size of charge.

  20. Re:Don't forget... by 10Ghz · · Score: 3, Informative

    "In short, the European politicians said, "If you want to stay in business, you MUST buy this spectrum at the prices we dictate""

    Ummmm, no. In several countries the licenses were handed out in a "beauty-contest", where the telcos only had to pay nominal fees. As to the countries that auctioned the liceses. They did not dictate the prices. The operators wanted those licenses and they competed between each other, THAT'S what drove the price up. Governments didn't dictate the price, it was settled in a bidding-war. In other words: the price was decided in an auction.

    --
    Lesbian Nazi Hookers Abducted by UFOs and Forced Into Weight Loss Programs - -all next week on Town Talk.
  21. Re:Minnow says "Hey we will win" by JanneM · · Score: 3, Informative

    True - but the coverage is not centered only in the densely populated aeras. /Janne

    --
    Trust the Computer. The Computer is your friend.
  22. FUD about GSM in Brazil by Fafhrd · · Score: 4, Informative

    This column has a lot of bias for CDMA, which is understandable, as the author has worked for Qualcomm. However, one of his points is basically FUD: the mention that Brazil has chosen GSM because of bribery.

    Brazil has started deploying GSM networks only this year. Previously, cellular companies used AMPS, which was later migrated to TDMA and CDMA, in different parts of the country. GSM was chosen as a new standard because it was the easiest upgrade path for TDMA, which was the largest installed base.

    For the public, GSM phones are selling like hotcakes here for one simple reason: the SIM card (or "personality chip", like it's called in the article) inhibits stealing service over the air. In Brazil, cell phone cloning is a widespread problem, and criminals actively monitor CDMA frequencies to grab handset codes to steal (certain regions are known as a hotbed of cloning, and people are advised to NOT turn on their phone when passing through, as the likelihood of being cloned is very high). This is not possible with GSM, as this depends on a key on the card.

    So, GSM is selling now, but it's not the entrenched standard, rather the upstart. And it's selling because it provides something that people in Brazil want, not because of bribery of the government, like the article alludes to.

    Disclaimer: I work for a GSM cellullar company in Brazil.

  23. Re:Not worth reading, but some here some facts... by gyc · · Score: 2, Informative

    1) There are many other countries that decided to have CDMA networks besides U.S., Korea, and Japan: Canada, China Mexico to name just a few off the top of my head.

    2) Spectrum: You have to buyu a lot more spectrum to switch from GSM -> UMTS then from CDMA -> CDMA 2000. Why? Because of the backwards compatibility of CDMA 2000, old CDMA phones can still communicate with CDMA2000 networks. Meanwhile, GSM operators will have to buy lots of new (expensive) spectrum, then for at least a while operate both the GSM and UMTS networks! (or they could give everyone new phones but that is equally as expensive).

    3) U.S. operators didn't go with CDMA2000 simply because it was developed by Qualcomm. U.S. CDMA operators went with CDMA2000 because of the backwards compatibility. AFAIK, the TDMA/GSM operators in the U.S. will probably go with UMTS.

  24. Re:GSM is better because of SIM ;-) by Anonymous Coward · · Score: 1, Informative

    GSM != SIM
    GSM = SIM + TDMA
    CDMA > TDMA
    CDMA != !SIM
    newGSM = WCDMA = SIM + CDMA

  25. Re:A Brit asks ... by Ronin441 · · Score: 4, Informative

    > how on earth did you Americans get to the insane pricing structure of your mobile phones?

    Easy -- it's the whole centralised versus distributed thing again. In sensible countries, the telephone standards body (Oftel, Austel, whoever) mandated a new set of phone numbers specifically for cell phones. For example, in Australia, all mobile phone numbers begin with 04.

    In the US, this sort of centralised control would be regarded as unamerican, and as such the work of Satan. Instead, each phone company set up their own numbering system. They all elected to work within the existing US ten-digit numbering scheme (I'd guess because they had to, based on what existing phone switches would handle). So in the US, a landline phone owned by a Las Vegas subscriber might have a number like 1 702 364 1234; but a Las Vegas cell phone subscriber might have a number like 1 702 682 1234.

    Now, if I'm calling you on your Las Vegas number, I can tell from looking at the area code (702) whether or not it's going to be a long distance call, and therefore how much I'm going to be billed. But I cannot tell from looking at the number whether I'm calling a landline or a cell phone; and it would therefore be unfair to bill me differently. So the phone company can only reasonably charge me, the caller, the same that they would charge for a regular call. But of course cell phone infrastructure is expensive, so someone's got to pay for it, and the only person left is you, the owner of the cell phone.

    Incidentally, when mobile phones first came out in Australia, there were several different payment plans that the subscriber could choose between. One was the American style, and one was the rest-of-the-world style. Guess which one everybody chose.