Mobile Communication

Cellular Telephony

Global System for Mobile Communication

GSM is the international cellular standard used throughout Europe, Asia, Australia, and parts of Africa. GSM operates in the 900 and 1800 MHz bands in Europe and Asia. GSM is also known in industry parlance as Digital Cellular System 1800 (or DCS 1800). Work started on the GSM standard as early as 1982 by a working group operating within the European Telecommunications Standards Institute. The original working group was called Group Speciale Mobile, hence the acronym GSM.

GSM (DCS 1800) is designed to include a wide variety of services including voice communication, message handling, facsimile, and data transmission. Today's DCS 1800 system uses radio spectrum ranging between 1710 and 1785 MHz and 1805 and 1880 MHz. GSM uses a combination of TDMA and FDMA. GSM provides a cell size of about 35 km. What this means for consumers is that cell phone users are able to buy one phone that will work anywhere the GSM standard is supported. GSM's implementation of TDMA varies somewhat from the U.S. approach and is, therefore, incompatible with IS-136. The GSM standard has proven highly successful throughout Europe and is a major reason for the proliferation of cell phones in that region of the world.