CDMA vs. GSM, Which One Is the Best for You?

Are you looking to pick a side between CDMA vs GSM, the two major telecommunication standards that are used by the cellular networks worldwide?

It can be a hard choice to choose between CDMA vs. GSM, as both have their own advantages. When in the hunt for a cell phone carrier, you may have to figure out which of these two technologies is the best for you and hopefully this article will shed some light on the whole CDMA vs. GSM issue.

The Origins of CDMA and GSM

CDMA: Code Division Multiple Access is a technology developed by Qualcomm in the United States, and it is currently the dominant network standard in North America.

GSM: Global System for Mobile communications was invented in 1987 by the GSM Association, an international organization dedicated to developing this standard worldwide.

CDMA was established earlier in North America and thus has a bit more coverage than GSM. GSM on the other hand is an international standard backed by an international organization and the protocol is a more mature and thus more robust. There is no clear winner in the CDMA vs. GSM debate here; it all depends on your needs.
Coverage of CDMA vs. GSM

CDMA: It is mostly used in America and some parts of Asia. It is currently making progress in other parts of the world, but the coverage is still limited compared to the GSM technology. Its support is currently non-existent in Europe because the European Union mandates the sole use of GSM. In North America however, CDMA generally offers a better coverage than GSM in some rural areas because it was deployed earlier. Its network reaches over 270 million users worldwide.

GSM: Being an international standard, it is better suited for international roaming, provided you own a quad-band cell phone (850/900/1800/1900 MHz). The GSM network is also well established in North America, but not as much as the CDMA network yet. Its network reaches over a billion users worldwide.

CDMA is prominent in North America, but GSM reaches a lot more users worldwide (about 1 billion vs 270 million). In the CDMA vs. GSM debate, GSM wins if you plan to travel to foreign countries but CDMA might have a better coverage in your area.
Data transfer

CDMA: The best data transfer technology it has to offer is the EVDO technology, allowing for a maximum download speed of about 2mb/s (about 700kbps in practice), which is similar to what a DSL line has to offer. EVDO is not available everywhere yet and requires a cell phone that is EVDO ready.

GSM: Offers EDGE, allowing for a maximum download speed of 384kbps (around 140kbps in practice). More technologies are being developed on top of EDGE such as HSDPA to boost the transfer rate to over 384kbps in practice. This technology requires an EDGE-ready cell phone.

CDMA offers faster data download and would therefore be the favoured choice for data transfer. GSM is catching up fast however, but its EDGE technology is subject to interferences.
Phone Identification (SIM cards)

CDMA: Your account information is programmed into your cellular phone. If you want to change your phone, you have to contact your carrier and have them reprogram your new phone. You will also need to re-enter your contact list and calendar information into your new phone. If you have a lot of contacts, your carrier might be able to help you perform this task. Some CDMA2000 cell phones support R-UIM cards (Removable User Identity Module) which are used to store account information and contact lists, but these are not very common in North America yet.

GSM: Your account information along with your contact list and other personal data are stored on a SIM card (Subscriber Identity Module). It is a small chip you can freely remove from your phone. When you get a new mobile device, you can simply insert your SIM card into it and it will work with your current account information and contact list. If you travel to another country, it might even be possible to purchase a prepaid SIM card which you can use to avoid roaming fees.

GSM is a clear winner here. The SIM card technology offers many advantages if you plan to travel or switch phone often.  CDMA phones are slowly catching up with R-UIM cards, but cell phones that make use of this technology as still rare.
Which technology is the best for me?

When asking yourself which technology to choose between CDMA vs. GSM, first ask yourself the following questions:

1. Is international roaming important to me? If you travel a lot to foreign countries, you might want to opt for a GSM phone for a better coverage.
2. Am I going to transfer a lot of data using the phone? If you intend to use the phone for mobile web browsing, watching television or downloading MP3s, you might be better off with a CDMA phone. Currently, it offers the best data transfer speed with its EVDO technology and is the clear winner for now.
3. Do I plan to change phone often? If you do, a GSM phone is best for you since you can swap the SIM card to a new device without having to re-enter your personal data.

Once you have established your basic needs, compare CDMA and GSM signals in your region. Also compare the carriers offering both services in your area. Talk to your friends and colleagues and ask them if they are satisfied with their cell phone carrier and how good their signal is. Remember, when choosing between CDMA vs. GSM, preferring a network technology over another also means limiting your choice in carriers.