Throughout the evolution of cellular telecommunications, various systems have been developed without the benefit of standardized specifications. This presented many problems directly related to compatibility, especially with the development of digital radio technology. The GSM standard is intended to address these problems.
From 1982 to 1985 discussions were held to decide between building an analog or digital system. After multiple field tests, a digital system was adopted for GSM. The next task was to decide between a narrow or broadband solution. In May 1987, the narrowband time division multiple access (TDMA) solution was chosen. A summary of GS.| Year | Milestone |
|---|---|
| 1982 | GSM formed |
| 1986 | field test |
| 1987 | TDMA chosen as access method |
| 1988 | memorandum of understanding signed |
| 1989 | validation of GSM system |
| 1990 | preoperation system |
| 1991 | commercial system start-up |
| 1992 | coverage of larger cities/airports |
| 1993 | coverage of main roads |
| 1995 | coverage of rural areas |
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