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In the telecommunications, a femtocell is a small, low-power cellular base station, typically designed for use in a home or small business. A broader term which is more widespread in the industry is small cell, with femtocell as a subset. It connects to the service provider’s network via broadband (such as DSL or cable); current designs typically support four to eight active mobile phones in a residential setting depending on version number, and eight to 16 active mobile phones in enterprise settings. A femtocell allows service providers to extend service coverage indoors or at the cell edge, especially where access would otherwise be limited or unavailable. Although much attention is focused on WCDMA, the concept is applicable to all standards, including GSM, CDMA2000, TD-SCDMA, WiMAX and LTE solutions. Use of femtocells benefits both the mobile operator and the consumer. For a mobile operator, the attractions of a femtocell are improvements to both coverage, especially indoors, and capacity. Coverage is improved because femtocells can fill in the gaps and eliminate loss of signal through buildings. Capacity is improved by a reduction in the number of phones attempting to use the main network cells and by the off-load of traffic through the user's network (via the internet) to the operator's infrastructure. Instead of using the operator's private network (microwave links, etc.), the internet is used. Consumers benefit from improved coverage since they have a base-station inside their building. As a result, the mobile phone (user equipment) achieves the same or higher data rates using less power, thus battery life is longer. They may also get better voice quality. The carrier may also offer more attractive tariffs, e.g., discounted calls from home. Femtocells are an alternative way to deliver the benefits of Fixed–mobile convergence (FMC). The distinction is that most FMC architectures require a new (dual-mode) handset which works with existing unlicensed spectrum home/enterprise wireless access points, while a femtocell-based deployment will work with existing handsets but requires installation of a new access point that uses licensed spectrum. Many operators have launched femtocell service, including Vodafone, SFR, AT&T, Sprint Nextel, Verizon, T-Mobile US, Zain, Mobile TeleSystems, and Orange. In 3GPP terminology, a Home Node B (HNB) is a 3G femtocell. A Home eNode B (HeNB) is an LTE femtocell. Typically the range of a standard base station may be up to 35 kilometres (22 mi), a microcell is less than two kilometers wide, a picocell is 200 meters or less, and a femtocell is in the order of 10 meters, although AT&T calls its product, with a range of , a "microcell". AT&T uses "AT&T 3G MicroCell" as a trade mark and not necessarily the "microcell" technology, however. == Overview and benefits == 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「femtocell」の詳細全文を読む スポンサード リンク
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