Many mobile phone users ask us what is the difference between GSM and CDMA wireless cellular services. If they can choose, which technology should they choose for their mobile phones or cellular terminals? This article provides a brief description of these two technologies and discusses the advantages and disadvantages of each technology.

GSM and CDMA

GSM and CDMA are two competing cellular network technologies. GSM-which stands for "Global System for Mobile Communications"-was introduced in 1987 as an international standard for mobile phones. It is currently the most popular standard in the world, with 5 billion users in 212 countries/regions. GSM is only used in Europe and other parts of the world. CDMA-which stands for "TelularAccess's Code Division Multiple Cellular Terminal"-was originally a proprietary standard developed by Qualcomm, but has evolved into a more dominant network standard in North America and parts of Asia. Now, there are more than 575 million CDMA users worldwide.

Although GSM mobile phone may be the main global wireless standard, it is not the only protocol used in developing countries. CDMA has a relatively good market share in many emerging cellular markets. Therefore, the low-cost terminal challenge issued by GSMA also extends to the CDMA world in a quiet manner.

Both technologies introduced the 3G (third generation) standard, which provides fast mobile broadband access to smart mobile phones and computer modems, and its follow-up product 4G is under development.

Incompatible technologies, but both are used in the United States

Both GSM and CDMA technologies transmit voice and data in different ways, which makes them incompatible.

Therefore, you cannot use a CDMA mible phone on the GSM network and vice versa. Competing operators use both technologies in the United States. CDMA is used by Verizon Wireless, Sprint and some smaller networks such as Metro-PCS and U.S. Cellular. GSM is used by AT&T/Cingular and T-Mobile.

The important thing to remember is that once you choose an operator, you must use a mobile phone or cellular terminal that is compatible with the network technology used by the operator.