2. GSM

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 GSM milestones is given in Table 2.

Table 2. GSM Milestones

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