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CDMA vs TDMA vs GSM

What network is best in your opinion? -Work with the same factors. Phone's dont make a difference nor does reception. I ...

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    Default CDMA vs TDMA vs GSM

    What network is best in your opinion?

    -Work with the same factors. Phone's dont make a difference nor does reception.

    I have heard CDMA is the best network out there (some thing about voice quality n stuff)

    GSM is nice for the sim card if you are a phone hopper.

    What do you think?

  2. #2


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    Default CDMA vs TDMA vs GSM

    GSM has slightly better voice quality. CDMA has slightly better data rates. Everyone agrees that TDMA is inferior to the two.

    GSM is the international standard. It is used in over 184 countries. GSM works by chopping up a conversation into timed bursts and seperates callers by time index and frequency (these are refered to as FDMA - frequency division multiple access - and TDMA - time division multiple access). Although its method of seperating calls is the same as that of TDMA, these are very different technologies. GSM currently uses 2 different codecs for encoding calls: EFR (enhances full rate) and AMR (advanced multi rate). These codecs were developed from the ISDN landline standard and offer very high call quality. GPRS (general packet radio service - the 2.5G data solution for GSM - offers data rates of up to 115kbps according to the International Telecommunications Union, but in reality will never exceed 64kbps. These networks exist in the US today and power networks by Cingular, ATTicon, T-Mobile and I'm sure some other small ones. The next iteration of GSM is called EDGE (enhanced data rates for GSM evolution) may or may not become a reality. It offers data rates up to 2Mbps according to the ITU which will translate into speeds of 384kbps for customers. The reason it may not become a reality is because as time goes on wCDMA - the stage after EDGE - gets closer and closer. wCDMA is a departure from the TDMA/FDMA way of splitting calls that GSM currently uses. wCDMA is a spread spectrum technology similar to CDMA, but over a wider frequency band than CDMA uses. wCDMA is sometimes refered to as UMTS (universal mobile telecommunications service), but they are acutally different - sort of. UMTS refers to wCDMA in a certain frequency band (2.1 or 2.4GHz I believe) not the technology itself, but many people use the UMTS name so that people realise that it isn't owned by Qualcomm. wCDMA does use one Qualcomm patent.

    CDMA is currently the dominant technology in the United States. CDMA works by having all of the calls transmitted on the same frequency at the same time. It identifies different calls by code. This, theoretically, gives CDMA an unlimited capacity under perfect conditions, but of course CDMA does have a limited capacity. There is only a certain ammount of noise that a channel can accomodate before the system and your phone can't recognise one signal from another. If you doubt the limitations of CDMA ask some angry Sprint customers in these forums complaining of network busy signals. Getting back to CDMA, it works to limit this noise by having a phone transmit at the lowest possible setting that will get the call through. One of the factors that determines how much power is need to transmit is distance from the tower. All phones have to take this into consideration. The other factor that only CDMA-type systems have to account for is the number of callers connected to the system. This is an example that one of the mods here (bobolito I believe) used: Say one person is 1 mi. from the tower using 1 watt to transmit. He is the only one connected to the system. Then another person joins the system from 1/2 mi. away transmitting at 1/2 watt. The person further away would have to up his transmition power so that the closer person's signal didn't totally cover his. As more people join the system the current people have to continue to up their power so that their call isn't drowned out by the new ones (think of people at a party talking. The more people talking the louder you're gonna have to talk). Also, the more people who are connected to the system means that there are more distances and more levels of transmitter power and the closer people are starting higher. Now there are 1000s of people connected and the people at 1/4mi. are using 1 watt, the people at 1/2 mi. are using 2 watts, and the people at 3/4 mi. are using 3 watts and the person at 1 mi. looses his connection because it is drowned out by the closer voices and he can't transmit more powerfully (talk louder) than 3 watts. In this way, CDMA coverage is variable in a way that TDMA/FDMA (and systems based on those principals) aren't. Beyond calling, that oversimplification shows how CDMA does have limitations even if everyone is at the same distance using the same transmitting power. 1xRTT - the 2.5G voice/data solution for CDMA - is currently deployed by Sprint and Verizonicon in certain areas. A lot of the times the carrier has implimented 1xRTT data, but not voice since the data is immiedately apparent. 1xRTT voice does offer some improvement in call quality, but not much and is still a tiny bit behind GSM's EFR codec. 1xRTT data improves data rates to a theoretical 144kbps, but again, in reality, it will never exceed 64kbps. After 1xRTT comes 1xEV-DO (data only/optimised) and 1xEV-DV (data/voice). 1xEV-DO has a theoretical 2Mbps, but will be 384kbps in the real world just like EDGE and wCDMA.

    TDMA is more accurately refered to as D-AMPS because that is what it is: digital analog. TDMA takes the old analog system and puts a bandaid on it by converting the signal to digital and adding a time division to it (analog is only divided by frequency). It is not much more advanced than that and is the only system that can handoff from digital to analog.

    In the end, TDMA won't exist and the evolutions of GSM and CDMA will have the same capabilities.

    Some related stuff...
    CDMA's soft handoff. This is something that people always bring up, but it really isn't so amazing. People claim that the signal spiders so that you are connected to 10 towers at a time, but it doesn't. Soft hand-offs are still hard (difficult to do). You are never talking through two towers at the same time (people often think well tower 1 will get part of what I'm saying and the rest will all get other parts and in real time it will all be compared with overlapping sections thrown out and the rest pieced together). The reality is that it would be impossible with the current technolgy to do that (plus, what happens when two of the same pieces are different - which is the correct signal). As previously brought up, edge signals like that are drowned out so that even if you are close enough to be transmitting to 10 towers, other signals would drown your's out in a CDMA system. The difference between a soft hand off and a hard hand off is make before break and break before make. CDMA uses a make before break meaning it connects to a new tower and the tower verifies the connection is better before it breaks the connection with the current tower. The new tower doesn't handle any parts of the call except analyzing the signal strenght until the connection with the previous tower has been terminated. TDMA and GSM use break before make systems (hard handoffs). This means that the tower you are currently connected to directs your phone and you disconnect from the current tower before connecting to the new one. While the CDMA system makes logical sense and is techncally superior, it hasn't proven that way in real life. Part of the downfall of soft hand offs is the fact that they are more difficult to engineer. This leads to soft and hard hand offs having about the same success rate. People always try to determine which is better from their personal experience of dropped calls, but that is faulty. People can't tell if their call was lost due to a gap in coverage or an ill-executed handoff - both drop your call in exactly the same way.

    TD-SCDMA is the new Chinese standard that shows a lot of promise. It is still in its infancy and is developed by Siemens and one of China's universities. It basically seperates signals by time and code. It is unknown how efficient this network is or even if it is viable at this time.

    People always mention analog roaming as an advantage to CDMA. This isn't true. I'm sure we've all seen the single band phones that Sprint sells. CDMA is not inherently compatable with analog. The only truely backward compatable technology is TDMA. Most CDMA phones have had analog capabilities added to them because Verizonicon wanted to slowly upgrade its network (way back when) and still haven't gotten to some areas where there is no reason to upgrade since they aren't taxing the bandwidth there and Sprint found that it couldn't get customers to overcome their fears of no coverage off their network. GSM phone manufacturers could have done this, but it wasn't important to them. CDMA handsets were bound almost entirely for the US where analog still existed en masse. In Europe, the destination for most GSM phones, providers needed to guarentee 99% population coverage for most licences. With GSM literally everywhere, there wouldn't be analog coverage where GSM wasn't so why bother. At the time, the US only had GSM from the companies that became T-Mobile and there wasn't a push to cater to them. Now that Cingular and ATTicon (as well as some others) are moving to GSM from TDMA/analog companies like Nokia and SonyEricsson (Siemens as well) have seen a larger US market for their phones and have begun to experiment with TDMA/GSM/analog hybrids that are just as compatable with analog as TDMA.

    The future...
    GSM will have coverage pretty equal to CDMA in the US when Cingular and ATT finish their upgrades and Western Wireless adds it to their network.

    wCDMA is GSM's ace. It allows CDMA and GSM carriers to upgrade to it easily. This would be the place that any CDMA carriers would jump ship since it would involve the same hassle to upgrade to it as it would to the continuation of CDMA. People will mention things like "Verizon has said it's happy with CDMA" not realising that corporations don't want to talk about any future plans and won't say they are unhappy with what they have to make sure that customers and potential customers think that they are having second thoughts about their own technology.

    The real world (or at least the real US)...
    CDMA and TDMA currently have coverage anywhere there is digital. Once Cingular and ATT finish their upgrades, GSM will be the same. From a user's standpoint GSM and CDMA offer nearly identical features and quality. GSM providers do seem to offer way more minutes though (Cingular, ATT, and T-Mobile offer 1000 anytime for $40/mo.). GSM does offer worldwide roaming and CDMA does have the most phones are analog compatable advantage, but those two difference may be short lived as Qualcomm tries to make a GSM CDMA hybrid and GSM phones are quickly gaining analog capabilities.

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    Default CDMA vs TDMA vs GSM

    Well, I most def cant give you as technical of a description, but I can tell you that CDMA is more used in the US, while GSM is used more in the rest of the world. If you’re not traveling out of the country with your phone, stick with CDMA.

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    Default CDMA vs TDMA vs GSM

    Everone seems to be chaning to GSM, AT&Ticon, Tmobileicon..... But, If they want to advance the technology further in the future, they will need to switch to CDMA. You can do a lot more with it.

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    Default CDMA vs TDMA vs GSM

    By move do CDMA do you mean move to Qualcomm's CDMA or simply a system that seperates calls by code rather than frequency/time?

    Either way, Qualcomm's CDMA (even 1xEV-DO/DV) hasn't surpassed what EDGE can do over an F/TDMA system.

    The whole argument is somewhat mute since if you had looked at the GSM evolution plan or my post you would have seen that the 3rd generation GSM technology is wCDMA (not related to Qualcomm's CDMA).

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    Default CDMA vs TDMA vs GSM

    The future is coming but not here yet... The important thing is go with the carrier that suits your needs. If you travel a lot especially out of major cities then gsm is a no no right now. If you stay put gsm offers more minutes for the money ( as long as there is a network where you live). Just make sure you do as short a contract as possible, because say you go with cdma now, gsm might meet you needs better in a year, or vice versa

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    Default CDMA vs TDMA vs GSM

    Originally posted by: RACERX8518
    The future is coming but not here yet... The important thing is go with the carrier that suits your needs. If you travel a lot especially out of major cities then gsm is a no no right now. If you stay put gsm offers more minutes for the money ( as long as there is a network where you live). Just make sure you do as short a contract as possible, because say you go with cdma now, gsm might meet you needs better in a year, or vice versa
    One of the best arguments I've heard. My only gripe is that you say that CDMA has better coverage when it should really read Verizonicon CDMA has better coverage. Sprintpcsicon won't give you better coverage than the average GSM provider (although they do have expensive analog roam).

    More than network technology, frequency band matters. Cellular carriers have better coverage because their towers transmit further and are FCC mandated to cover 80% of the land area that they have licences in. Most cellular carriers, including Verizonicon, do not have licences in all areas (also Verizon is PCS in certain areas). PCS carriers are only mandated to cover 80% of the population.

    If you would like to see where Verizon has licences check out: http://www.verizonwireless.com/image...repay_natl.gif
    The light green is where they have PCS licences and the blue and dark green are where they have cellular licences (the dark green areas are where Verizon has not yet upgraded to digital technology). Outside of those areas Verizon has no service. That does not mean that your phone will have no service. Verizon has many roaming agreements.

    If you are curious as to Cingular's GSM rollout, there current coverage can be found at: http://onlinestore.cingular.com/imag...L_12_08_02.gif. Cingular isn't selling service in all areas yet, but they have put up a lot of coverage.

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    Default CDMA vs TDMA vs GSM

    (A reprint of a post I made in the Howard Forums)

    Here are some facts about GSM I just made up:

    1: GSM has unlimited voice capacity.

    2: A GSM network provides seamless and uninterrupted coverage in the areas it serves

    3: GPRS lowest data rate is 4.32 Mbps (up and down link) using 300 time slots (Class 750).

    4: GSM uses DTS-ES Discrete 6.1 Surround Sound in its vocoders that sample at 144kbps with 0.00001% distortion.

    5: GSM SIMS can store all of the information contained by all of the websites on the internet.

    6: GSM phones with color screens use True 32 bit color, 16:9 aspect ratio and average 13 inches diagonally.

    7: Bluetooth equipped GSM phones are self configuring and all-knowing.

    8: Only the Europeans know how to use GSM and know what is best for us with regard to personal communications.

    9: The Symbian OS is capable of running apps that can model the physics of a Black Hole and sorting all of the information stored in the SIM (see #5).

    10: GSM does not use TDMA but rather, it uses a form of arcane magic practiced on an obscure planet oribiting Sirius.

    [img]i/expressions/face-icon-small-happy.gif[/img]

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    Default CDMA vs TDMA vs GSM

    Originally posted by: emag0rad
    (A reprint of a post I made in the Howard Forums)

    Here are some facts about GSM I just made up:

    1: GSM has unlimited voice capacity.

    2: A GSM network provides seamless and uninterrupted coverage in the areas it serves

    3: GPRS lowest data rate is 4.32 Mbps (up and down link) using 300 time slots (Class 750).

    4: GSM uses DTS-ES Discrete 6.1 Surround Sound in its vocoders that sample at 144kbps with 0.00001% distortion.

    5: GSM SIMS can store all of the information contained by all of the websites on the internet.

    6: GSM phones with color screens use True 32 bit color, 16:9 aspect ratio and average 13 inches diagonally.

    7: Bluetooth equipped GSM phones are self configuring and all-knowing.

    8: Only the Europeans know how to use GSM and know what is best for us with regard to personal communications.

    9: The Symbian OS is capable of running apps that can model the physics of a Black Hole and sorting all of the information stored in the SIM (see #5).

    10: GSM does not use TDMA but rather, it uses a form of arcane magic practiced on an obscure planet oribiting Sirius.

    [img]i/expressions/face-icon-small-happy.gif[/img]
    Actually, it's Dolby Digital not DTS. CDMA uses DTS[img]i/expressions/face-icon-small-smile.gif[/img]

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    Default CDMA vs TDMA vs GSM

    4: GSM uses DTS-ES Discrete 6.1 Surround Sound in its vocoders that sample at 144kbps with 0.00001% distortion.

    Coolio!

    So have they released any 5.1 personal speaker systems for any of the major phones out there - possibly using Nokia's Pop-Port connection?!?

    I guess my only concern is where I'll put the subwoofer - guess I'll have to wear a backpack from now on

    LOL! [img]i/expressions/face-icon-small-wink.gif[/img]

    s.

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    Default CDMA vs TDMA vs GSM

    Hey Northform, a T-Mobileicon customer in California or Nevada is actually roaming on Cingular, correct? If so, why did Cingular build out this 1900 mHz GSM coverage and how long have they had it? They don't sell 1900 mHz GSM phones, right? it just seems odd to me that they would just randomly have some 1900 GSM coverage, when they've traditionally been a TDMA provider who has only recently started building out 850 GSM. Maybe I'm just confused....

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    Default CDMA vs TDMA vs GSM

    Well, Cingular was formed by the merger of the SBC, Bell South, and Pac Bell wireless units. Pac Bell used GSM while the rest of the network was TDMA. Cingular does sell GSM1900 in CA and NV and has begun to roll out GSM1900 in markets where they have 1900 licences. Areas where they own 1900 or both types of licences will see GSM1900 followed by GSM800 if they have an 800 licence. Areas where they don't have 1900 licences will just see GSM800.

    T-Mobileicon and Cingular created an agreement a little while ago that would allow Cingular to begin selling wireless service in NYC and T-Mobileicon to sell wireless in CA and NV. It would also allow customers to roam from one service to another if they went out of their carriers service area. Technically, both companies jointly own the licences in NYC, CA, and NV according to FCC filings.

    So T-Mobile customers are no more roaming on Cingular's network in CA than Verizonicon customers are roaming on Bell Atlantic Mobile's network in the northeast.

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    Default CDMA vs TDMA vs GSM

    http://www.topnic.com/cgi/read.cgi/t57964615

    Which network--CDMA or GPRS? No easy answers

    By David Berlind
    January 13, 2003

    Microsoft's recent announcement that it has added CDMA support to the phone edition of PocketPC is an important story to any corporate customer traveling the WAN upgrade road.

    Microsoft's announcement makes it possible for manufacturers of PocketPC Phone Edition-based PDA/phones (like Samsung) to supply devices to operators of CDMA networks (like Sprinticon and Verizonicon) in addition to the operators of GSM/GPRS networks (like T-Mobileicon and Cingular) with which PocketPC Phone Edition was already compatible. GSM handles voice, while GPRS (General Packet Radio Service)handles data.

    The cross network availability also broadens the target for developers of wireless applications that depend on a PocketPC based client. Prior to this announcement, if you or your company depended on PocketPCs and you wanted to mobilize an application using PocketPC Phone Edition, you only had one choice for a wide area data network: GPRS.

    As a side note, Microsoft was late to the cross-network party. The PalmOS-powered Treo PDA/phones from Handspring are already available for both networks. The other competition to Microsoft on the mobile operating system front --- Symbian (of which Nokia and Samsung are licensees) --- also supports both networks.

    Now that all three mobile operating systems support both voice/data networks, the next question facing corporate developers/users and consumers who didn't have to think about the network before is: Which network?

    To answer this and other questions, I contacted John Strand, of Copenhagen-based Strand Consult, who recently authored a report that said GPRS has so far been a bigger flop than WAP.

    As it turns out, there's nothing wrong with GPRS -- at least nothing that we don't already know. Strand was referring to GPRS' as yet unfulfilled potential from the operator's side of the equation. But, for users, there are differences between the networks. For example, despite the advertised data rates of both networks, Strand notes, "most GPRS users are lucky if they get between 32 and 36 KBps. CDMA users are getting at least twice that--somewhere between 70 and 80 KBps." This corroborates some positive feedback I've heard about the performance of Sprinticon's PCS network when compared to the GPRS-based alternatives.

    Simply because CDMA is going twice as fast as GPRS, and exciting services like Sprint's video phone look, well, exciting, doesn't mean that we should all run to CDMA, says Strand. Since pricing for similar bundles of voice and data from both camps are about the same, it would seem as though you get more bang for your buck from CDMA.

    But Strand advises users to consider other criteria before making a decision.

    "The most obvious one," says Strand, "is coverage. Going with CDMA won't be very helpful if most of your people are running around in area that doesn't have very good CDMA coverage." The same goes for GPRS.

    Assuming that you or "your people" run around in areas covered equally by both networks, your next consideration should be the applications you are running. Strand divides applications into three tiers: light, medium and heavy.

    "Light applications" says Strand, "are ones like e-mail that don't require a lot of bandwidth. Medium apps are the type where you need real-time access to facts and figures and are submitting database queries and things of that nature. Heavy apps include streaming video clips, working with large images, or downloading big documents like PowerPoint or Word documents."

    Either network will suffice for applications whose maximum bandwidth requirement falls somewhere between medium and heavy, says Strand. But once you enter the world of heavy, CDMA is your only choice. E-mail is pretty light, until you enter the world of Microsoft Office and PocketPC. Given PocketPC's support of documents created in Word and Excel (and similar functionality that can be had on PalmOS and Symbian), we certainly aren't discouraged from sending or receiving large documents. If your users like to take full advantage of a mobile device's capability to work with MS-Office documents, then CDMA certainly looks good on paper.

    Value added by operators
    Another area that Strand suggests looking into is the menu of value-added services provided by the mobile operator. Strand is particularly critical of American operators. "Whereas other operators around the world will show you a road map for the additional services and APIs that they're going to make available over time, American operators are little more than dumb ISPs," he says. Leaving room for one or two innovative offerings like Sprint's Business Connection, Strand says, "for the most part, American operators offer two things--voice and data." It's no wonder that users and companies have no idea which way to go when choosing networks.

    Strand points to South Korea as a country that has fully embraced a single infrastructure (CDMA) and where the operators are proactive about value-added services because they represent the biggest opportunity for additional revenue. The Korean operators also are keen on making those services available to third-party developers through APIs.

    Provided the right APIs are available, a developer could write an application that allows a phone user to assign a voice or data transmission to a client's account, and integrate the charges into a billing system (regardless of where it is hosted). Sounds like a job for Web services.

    That corresponds to the answers Microsoft gave me when I asked if PocketPC developers needed any "IF-THEN-ELSE" statements in their source code to deal with network dependencies. If that was the case, then understanding those network dependencies might affect the GPRS vs. CDMA decision. According to Microsoft's Jason Gordon, that depends on the mobile operators and what APIs they make available to developers. Right now, says Gordon, there's no difference. Like Symbian and Palm, PocketPC's equal access to both networks will help to level the playing field for developers. Eventually, if the operators do come up with services that they want to make available to developers, their best bet will be to work with the operating system providers to make sure that the APIs to those services are exposed in Software Development Kits (SDKs).

    Can mobile operators change their spots? Despite the glut of bandwidth, the telecommunications service providers (land and air) continue to overcharge for voice and data. Sooner or later, if public 802.11 networks don't come from nowhere and kill 3G altogether, that market dynamic is going to come back to haunt them. When it does, the operators that survive may very well be the ones that can transform themselves from pipe providers to platform providers. Who that will be is anyone's guess.

    Unfortunately, this is one important data point that's tough to fill in if you are trying to make an informed decision today.


    What has your experience been with CDMA and GPRS? Share your thoughts and opinions using TalkBack below, or write to me at [email protected].

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    Default CDMA vs TDMA vs GSM

    I feel that the relative merits of various 3G technologies are of theoretical value and of no use to me as a consumer today.

    My approach to cellular phones over the last several years has been simple.

    Every year, I evaluate all the cellular providers for their coverageand plans being offered as a promotion. I pick the one that has the best coverage for my lifestyle - predominantly urban with free roaming in the western US. I pick the dealer (local or online) that has the best phone for the lowest price (typically free) when combined with a new contract. I then sign up for a maximum of a 1-year contract.

    At the end of the 1 year, I redo the above process. I am thus guaranteed to be no more than 1 year behind the best cellular
    technology, provider (for my lifestyle), plan and handset. The only drawback with my plan is that I have a new cellphone # every year - I don't care. I also don't see why I should pay premium $ for an after-market phone just so I can avoid a 1 year contract - I have never paid for a single phone I've owned and I feel that I can reasonably predict my phone usage for the next 1 year so that I don't have the need to switch before my contract is up.

    So, T-Mobile/ATT/Verizonicon/Sprint, CDMA/GSM, WCDMA/CDMA2000 - bring 'em on! As an American consumer I say - long live the free market, and I will pick the best deal out there every year!

    - Sam
    "If I don't practice the way I should, then I won't play the way that I know I can." - Ivan Lendl

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    Default CDMA vs TDMA vs GSM

    There's a couple of things that were said here and are innacurate so I am sticking my nose to correct them:

    - CDMA DOES handoff to analog. However, analog cannot go back to CDMA. I've seen it happen myself.
    - CDMA handoffs are controlled by the phone, not the towers. The phone dictates when to connect or disconnect from a tower.
    - CDMA and TDMA carriers use the ANSI-41 core network which is what's behind the air interface taking care of billing, OTA and roaming permissions. The fact that TDMA and CDMA carriers run the same ANSI-41 network is what makes possible for your phone to be located so it can ring when you are analog roaming in a totally different carrier network. You can be a TDMA native user and be on Verizonicon's analog system and if roaming agreements are set, your TDMA phone will work on Verizonicon's analog network. This cannot happen, however, with GSM carriers. Carriers who use WCDMA will be using the GSM MAP network which means they cannot natively roam or connect to ANSI-41 carriers. This is why CDMA carriers who wish to migrate to WCDMA will have a steep mountain to climb, not to mention the high cost. It is much easier for them to stick to their CDMA path and migrate to CDMA2000. Only recently, there are efforts to allow both core nets to communicate with each other and that's why there are developments of these hybrid phones like GSM/CDMA and GAIT. This is why GSM roaming on analog was not possible but it is now thanks to GAIT. It is like marrying the Macintosh with the PC.
    "Jobs was brave enough to think differently, bold enough to believe he could change the world, and talented enough to do it."
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    Default CDMA vs TDMA vs GSM

    Originally posted by: bobolito
    There's a couple of things that were said here and are innacurate so I am sticking my nose to correct them:

    ...that TDMA and CDMA carriers run the same ANSI-41 network is what makes possible for your phone to be located so it can ring when you are analog roaming in a totally different carrier network. You can be a TDMA native user and be on Verizonicon's analog system and if roaming agreements are set, your TDMA phone will work on Verizonicon's analog network. This cannot happen, however, with GSM carriers. Carriers who use WCDMA will be using the GSM MAP network which means they cannot natively roam or connect to ANSI-41 carriers. This is why CDMA carriers who wish to migrate to WCDMA will have a steep mountain to climb, not to mention the high cost. It is much easier for them to stick to their CDMA path and migrate to CDMA2000. Only recently, there are efforts to allow both core nets to communicate with each other and that's why there are developments of these hybrid phones like GSM/CDMA and GAIT. This is why GSM roaming on analog was not possible but it is now thanks to GAIT. It is like marrying the Macintosh with the PC.

    This is confusing.....HELP !!!!
    I understand the part about roaming agreements with the analog systems, but it doesn't fully explain why phone manufactures have decided not to implement analog in their GSM phones(with the exception of the Nokia 6340). You state it's because of the ansi-41 carriers, but that doesn't fully expain it. Doesn't the analog part of the phone connect to the analog network ?? Doesn't the analog part of the phone tell the analog network what provider you are with so they can figure out how to bill you? Analog is analog is analog. IE - it's not a technology thing, it's an agreement thing, so why have the manufactures stopped making use of good old AMPS 800 as a fallback. I'm sure several years in the future this won't be an issue as digital networks continue to grow, but I live in the now unfortunately....

    Does anyone know of any GSM providers that allow the use of the Nokia 6340 ??

    Thanks

  17. #17

    bobolito's Avatar
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    Default CDMA vs TDMA vs GSM

    Cingular is the only provider that uses the 6340.

    Just a clarification: Analog, TDMA and CDMA ALL run on the ANSI-41 core. This is why roaming is easily implemented on them. GSM runs on a different core network.
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    Default CDMA vs TDMA vs GSM

    Thanks, unfortunately, cingular doesn't offer it in my area...in fact, they don't offer any digital/analog phones in my area, only digital [img]i/expressions/face-icon-small-sad.gif[/img]

    I understand that GMS doesn't run on the ansi-41 core, however if the phone had analog, wouldn't the analog part use the ansi-41 core?? Why is it so difficult to have both in one phone? Guess I just don't get it...

    thanks



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    Default CDMA vs TDMA vs GSM

    The difficult part is not the phone side. It's the network side. Your native (or home) core network has to communicate with the foreign core network before you can use your phone. That requires a gateway. It's like trying to get a Macintosh to talk to a PC. You need a "translator" in between. To get this to work you need to invest money. Previously there was no interest in getting the two networks to talk to each other. Now, things have changed.
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    Default CDMA vs TDMA vs GSM

    Re Northform's statement:

    CDMA is not inherently compatable with analog.

    Perhaps inherently is the key word here.

    Verizonicon followed SK Telecom's lead by upgrading 800 MHz AMPS to 800 MHz CDMA. The towers shared the available channels allocating some to AMPS and the rest to CDMA according to usage. SK Telecom has upgraded to CDMA2000 1X (Oct 2000) and now to 1XEV-DO.

    I would say that based on the experience of Verizonicon and SK Telecom that CDMA and AMPS are rather compatible.

    I am a customer of both companies. From 1994 through 1998, I had an OKI 900 registered both in the US and on SK Telecom. I upgraded my SK Telecom account to CDMA in mid 1998.

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    Default CDMA vs TDMA vs GSM

    Originally posted by: northform

    If you would like to see where Verizonicon has licences check out: http://www.verizonwireless.com/image...repay_natl.gif
    The light green is where they have PCS licences and the blue and dark green are where they have cellular licences (the dark green areas are where Verizonicon has not yet upgraded to digital technology). Outside of those areas Verizon has no service. That does not mean that your phone will have no service. Verizon has many roaming agreements.

    If you are curious as to Cingular's GSM rollout, there current coverage can be found at: http://onlinestore.cingular.com/imag...L_12_08_02.gif. Cingular isn't selling service in all areas yet, but they have put up a lot of coverage.
    One thing to note...

    The Verizon map shown here is not correct if in fact the dark green areas are where Verizon has not yet upgraded. As I'm in few of those areas often and they are 1xRTT, so, I guess your mileage will vary with coverage maps, as (and we all know) they're always changing.

    Another thing to note, is that even though Cingular posts that GSM map. Most of that network is not theirs. As you see, it's the "preffered nation" map. Most of the network shown is T-Mobileicon's. I think Cingular has most of their GSM out on the west coast right now and not too much more, except for sporadic high density metro areas where they can (obviously) make the most money initially...

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    Default CDMA vs TDMA vs GSM

    It seems the 800 pound gorilla of handsets has an opinion on the upgrade path carriers should follow. Northform and the others who are technically well versed, how do you think this will change the scene?



    <DIV class=hugin>IRVING, TEXAS - Nokia (NYSE: NOK), the expert in mobility, confirms that evolution of its CDMA2000 mobile station chipset supporting IS-2000 Release C (also known as 1xEV-DV) is on schedule for field trials with CDMA operators during the 2nd half of 2003. Nokia believes that 1xEV-DV represents the logical next step for incumbent CDMA operators upgrading their existing CDMA2000 1X (IS-2000 Release 0) networks. Already a major supplier of IS-95 and CDMA2000 1x handsets based on Nokia's own chipsets, Nokia plans to develop and market new terminals based on Nokia-designed CDMA2000 1x EV-DV chipsets.</DIV>

    <DIV class=hugin></DIV>

    <DIV class=hugin>"CDMA operators must carefully choose the next step in evolving their networks and maximizing existing investments from several possible evolution options," said Adam Gould, chief technology officer of CDMA for Nokia Mobile Phones. "The key considerations when choosing an evolution path should be efficient spectrum usage, maximum deployment flexibility, backwards compatibility for legacy handsets and support for the broadest range of applications including those requiring simultaneous voice and high speed data. For operators committed to a CDMA2000 1X migration path, 1xEV-DV is the best evolution option to satisfy these considerations." </DIV>

    <DIV class=hugin></DIV>

    <DIV class=hugin>CDMA2000 1xEV-DV offers the flexibility to dynamically balance voice and data traffic by allocating bandwidth on demand and allows for the performance of two high-value tasks simultaneously on a single RF section device. Unlike other CDMA standards like 1xEV-DO, 1xEV-DV creates a more attractive cost structure for operators with its combination of flexible network resource allocation and its ability to support concurrent voice and data services.</DIV>

    <DIV class=hugin></DIV>

    <DIV class=hugin>"Nokia is aggressively moving forward with 1xEV-DV technology development in preparation for the data-intensive products and applications that will be launched in the near future. 1xEV-DV deployment will coincide with increased demand by mobile users for the kinds of data rates it has to offer," continues Gould. "The applications and services now becoming available on 1X networks are creating increased expectations for future service offerings by 1X operators that only evolution to 1xEV-DV can satisfy."</DIV>

    <DIV class=hugin></DIV>

    <DIV class=hugin>Nokia is currently in discussions with multiple CDMA stakeholders to cooperate in 1xEV-DV interoperability testing and field trials. </DIV>

    <DIV class=hugin></DIV>
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    Default CDMA vs TDMA vs GSM

    I have ZERO interest GSM cell phones.

    GSM makes sense if the phone used is issued by an employer and the employee travels internationally often.

    I travel to rural U.S. areas frequently to hunt and fish and you're screwed without the ability to switch to analog service. Perhaps in a few years when GSM service is more prevalent, it might make sense to go GSM, but not now, at least not for me.

    Take a look at a T-Mobileicon coverage map. Entire states have virtually no coverage whatsoever.

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    Default CDMA vs TDMA vs GSM

    I use the T-Mobileicon coverage map when my US Atlas CD is not available. Nice markings on the highways [img]i/expressions/face-icon-small-wink.gif[/img]...
    "Jobs was brave enough to think differently, bold enough to believe he could change the world, and talented enough to do it."
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    Default CDMA vs TDMA vs GSM

    Originally posted by: Kieran
    I have ZERO interest GSM cell phones.

    GSM makes sense if the phone used is issued by an employer and the employee travels internationally often.

    I travel to rural U.S. areas frequently to hunt and fish and you're screwed without the ability to switch to analog service. Perhaps in a few years when GSM service is more prevalent, it might make sense to go GSM, but not now, at least not for me.

    Take a look at a T-Mobileicon coverage map. Entire states have virtually no coverage whatsoever.
    ...unless you get a GAIT phone from Cingular.
    I can help you in English. Puedo ayudarle en español. Je peux vous aider en français. Posso aiutarli in italiano. Ich kann Sie auf Deutsch helfen. Я могу помочь вам по-русски.

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    Default CDMA vs TDMA vs GSM

    Originally posted by: ZaphodB
    Originally posted by: Kieran
    I have ZERO interest GSM cell phones.

    GSM makes sense if the phone used is issued by an employer and the employee travels internationally often.

    I travel to rural U.S. areas frequently to hunt and fish and you're screwed without the ability to switch to analog service. Perhaps in a few years when GSM service is more prevalent, it might make sense to go GSM, but not now, at least not for me.

    Take a look at a T-Mobileicon coverage map. Entire states have virtually no coverage whatsoever.
    ...unless you get a GAIT phone from Cingular.
    But then you can not travel internationally - no 900 MHz and no 1800 MHz on the GAIT phones.


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