1st Generation of systems for mobile communications (1G) were primarily analog, lacking the capability for data communication, and had limited international roaming capabilities. Various systems existed, each utilizing different frequency bands, channel widths, and channel spacing.

In Europe, 1G mobile telephony systems operated within the 450 MHz and 900 MHz frequency bands. The primary analog standards included TACS (Total Access Control System) and NMT (Nordic Mobile Telephone). Additionally, different national standards were employed in countries like France, Germany, and Italy:

1. Nordic Mobile Telephone 450 MHz (NMT-450) was used in several countries.
2. Nordic Mobile Telephone 900 MHz (NMT-900) was utilized in specific European nations.
3. (Extended) Total Access Communication System 900 MHz (ETACS) found use in several countries.
4. Netz-C 450 MHz was employed in Germany, Portugal, and South Africa.
5. Radiocomm 2000 operated in France, spanning both 450 and 900 MHz bands.
6. In the United States and Canada, the prevalent cellular system was AMPS
7. Japan adopted the NTT System 900 MHz and a Japanese version of TACS 900 MHz.