Multi-band device
type of mobile phone
In telecommunications, a multi-band device (including (2) dual-band, (3) tri-band, (4) quad-band and (5) penta-band devices) is a communication device (especially a mobile phone) that supports multiple radio frequency bands. All devices which have more than one channel use multiple frequencies; a band however is a group of frequencies containing many channels. Mobile carriers use multiple bands, internationally, to communicate with their telecommunications infrastructure. Multiple bands in mobile devices support roaming between different regions where different standards are used for mobile telephone services. Where the bands are widely separated in frequency, parallel transmit and receive signal path circuits must be provided, which may impact the manufacturing cost of multi-band devices due to increased circuit complexity.
The term quad-band describes a device that supports four frequency bands: the 850 and 1900 MHz bands, which are used in the Americas, and 900 / 1800, which are used in most other parts of the world. Most GSM/UMTS phones support all four bands, while most CDMA2000/1xRTT phones (mostly North America and voice transmission only) do not, and so are considered only dual-band devices. A few phones support both of the domestic frequencies but only one foreign one for limited roaming, making them tri-band phones.
The term penta-band describes a device that supports a fifth frequency band, commonly the 1700/2100 MHz band in much of the world. The Advanced Wireless Services (AWS) 1700 MHz band is also seeing increased usage.
“Multi-band device” enters the record as type of mobile phone. Crown Archives preserves that source wording while asking what Multi-band, device and type can confirm, complicate or overturn.
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This entry incorporates text from “Multi-band device” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.