The use of GSM frequency in the United States In North America, GSM operates the main mobile communication bands -850 MHz and 1900 MHz. The initial implementation was completely 1900 MHz, and 200 1 increased by 850 MHz. In Canada, GSM- 1900 is the main frequency used in urban areas, 850 is the backup, and GSM-850 is the main frequency in rural areas. In the United States, management requires determining which frequency region can be used.

GSM- 1900 and GSM-850 are also used in parts of South America and Central America. At least one country fully uses GSM-850. Some countries use GSM-900 or GSM- 1800 in the United States.

In the United States, some countries use GSM- 1900 telephone:

Antigua island, Argentina, Belize, Bermuda, Bolivia, Canada (using GSM-850), Chile, Colombia, Dominican Republic, Mexico, Paraguay, Peru, Puerto Rico, Trinidad and Tobago, United States (using GSM-850), United States Virgin Islands, and British Welsh Islands (using GSM-900).

In the United States, some countries use GSM-850 phones:

Panama, Ecuador, Montserrat, USA (using GSM- 1900), Canada (using GSM- 1900), Turks and Caicos.

In the United States, some countries use GSM-900 phones:

Brazil, Venezuela, Greenland, Suriname, French Guiana, Saint Pierre and Miquelon Islands, British Wells Islands (using GSM- 1900).

In the United States, some countries use GSM- 1800 telephone:

Brazil, Costa Rica

GSM-400 is used in Tanzania.

Europe and America also have mobile phones such as GSM450, which are mainly used in mountainous areas and belong to 2-2.5 generation communication systems.

Some countries do not use GSM, including Japan and South Korea.