 | This articlerelies largely or entirely on asingle source. Relevant discussion may be found on thetalk page. Please helpimprove this article byintroducing citations to additional sources. Find sources: "MTD" mobile network – news ·newspapers ·books ·scholar ·JSTOR(May 2024) |
MTD (Swedish abbreviation forMobiltelefonisystem D, orMobile telephony system D) was a manualmobile phone system for the 450 MHzfrequency band. It was introduced in 1971 inSweden, and lasted until 1987, when it was made obsolete by theNMT automatic service.[1] The MTD network had 20,000 users at its peak, with 700 people employed as phone operators.[citation needed]
MTD was also implemented inDenmark and inNorway (from 1976), which allowed roaming within theScandinavian countries.
In Sweden, the first mobile phone system was MTA (forMobiltelefonisystem A), which was introduced in 1956, and lasted until 1967.[1] It was a 160 MHz system available inStockholm andGothenburg, with 125 total subscribers.[citation needed] The second system, MTB (forMobiltelefonisystem B), hadtransistorized mobile sets, was introduced in 1962, and lasted until 1983. It operated in the 76–77.5 and 81–82.5 MHz bands, was also available inMalmö, and had around 600 subscribers.[1]
In Norway, the first mobile phone system wasOLT, introduced in 1966. In 1976, the OLT system was extended to includeUHF bands, incorporating MTD, and allowinginternational roaming within Sweden.[citation needed]
Cellular network standards | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 0Gradio telephones (1946) | |||||||||
| 1G (1979) |
| ||||||||
| 2G (1991) |
| ||||||||
| 2G transitional (2.5G, 2.75G, 2.9G) |
| ||||||||
| 3G (1998) IMT-2000 (2001) |
| ||||||||
| 3G transitional (3.5G, 3.75G, 3.9G) |
| ||||||||
| 4G (2009) IMT Advanced (2013) |
| ||||||||
| 5G (2018) IMT-2020 (2021) |
| ||||||||
| Related articles | |||||||||
