Explanation of GSM/CDMA/TDMA

I have cingular service. I am not necessarily unhappy with it as it serves my family's needs. However, my phone is crap. I have the V551 moto and this is the second one. So, yes this is a cingular refurb model. But I have been looking at ebay, craigslist, yahoo and such for another cingular phone and I am totally confused. Some say verizon/att/cingular use the same phones (just switch the sim) others say absolutely not the same phones. Can anybody help explain this. Thanks.

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› See More: Explanation of GSM/CDMA/TDMA

well, here's a simple answer.

gsm: this is the technology used by cingular and t-mobile. there are other carriers, but those are the big 2. gsm uses sim cards inside the phone.

cdma: this technology is used by carriers such as verizon, sprint, us cellular, altel, etc.. basically, if you're not using a gsm carrier in the US, you're cdma.

iden: that's nextel and boost. they also have sim cards, but are not compatible with gsm phones.

now to replace your cingular phone...

the easiest option is to get a cingular branded phone (store, ebay, for sale forum, etc..). the next option is to get an unlocked gsm phone. if/when you do this, make sure it has the 850/1900 bands as a minimum. a lot of unlocked gsm phones for sale online are european and can/will reduce your service. and if you use the internet and messaging, you'll have to change the settings in an unlocked phone other than cingular branded. but you'll find help on that here.

hopefully that helps you out. happy hunting!

To add to the previous post:

The most common technologies being used now a days is GSM and CDMA, TDMA is being fade out.

GSM: AT&T, Cingular, T-Mobile etc...

Global System for Mobile Communication.

GSM is the dominant 2G digital mobile phone standard for most of the world. It determines the way in which mobile phones communicate with the land-based network of towers.

GSM is one of two major mobile phone technologies in the U.S. The other is CDMA. Cingular and T-Mobile use GSM. Sprint and Verizon use CDMA. GSM is more prevalent in most other parts of the world, and especially in Europe.

Although GSM and CDMA provide similar basic features and services to end-users, (such as voice calling, text messaging, and data services,) they operate very differently at many technical levels. This makes GSM phones completely incompatible with CDMA networks, and vice-versa.

The most visible feature of GSM are SIM cards. SIM cards are removable, thumbnail-sized smart cards which identify the user on the network, and can also store information such as phone book entries. SIM cards allows users to switch phones by simply moving their SIM card from one phone to the other.

CDMA: Verizon, Sprint, Alltel, etc...

(Code-Division Multiple Access.)

CDMA is a digital wireless technology. It is a general type of technology, implemented in many specific technologies. But the term "CDMA" is also commonly used to refer to one specific family of technologies (IS-95 and CDMA2000) that competes with technologies such as GSM.

CDMA is a "spread spectrum" technology, which means that it spreads the information contained in a particular signal of interest over a much greater bandwidth than the original signal.

Unlike many competing technologies, CDMA has no hard limit for the number of users who may share one base station (tower). Instead, with CDMA, additional users can connect until the base station determines that call quality would suffer behind a set limit.

CDMA (IS-95) systems have been in commercial operation since 1995. CDMA networks operate in the 800 and 1900 MHz frequency bands with primary markets in the Americas and Asia. IS-95 CDMA systems are sometimes referred to as cdmaOne. The next evolutionary step for CDMA to 3G services is cdma2000.













source p/s

thanks for adding in all the data i omitted for simplicity, tony!

Originally Posted by n1ckel5

thanks for adding in all the data i omitted for simplicity, tony!

It wasn't posted for you. just in case someone needs reading material..