Types

• North American cell phones use a number of technologies, including the Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA) digital networks. In Europe cell phone technology has been standardized with the Global Standard for Mobile Communication (GSM) network, which is incompatible with the TDMA and CDMA networks.
  
  

Frequency

• The Let's Talk website explains that some North American cell phone providers have begun developing GSM technologies. North American GSM cell phones operate on a frequency of 1900 MHz, which is incompatible with European cell phones operating on frequencies between 900 and 1800 MHz.
  
  

Technology

• The standard GSM technology was designed for use in Europe and employs a combination of technology from CDMA and TDMA cell phones. GSM cell phones encode a call and allow between eight and 10 calls to be transmitted at one time on a single frequency.