Small cell

Small cells are low-powered radio access nodes that operate in licensed and unlicensed spectrum that have a range of 10 meters to 1 or 2 kilometers. They are "small" compared to a mobile macrocell, which may have a range of a few tens of kilometers. With mobile operators struggling to support the growth in mobile data traffic, many are using mobile data offloading as a more efficient use of radio spectrum. Small cells are a vital element to 3G data offloading, and many mobile network operators see small cells as vital to managing LTE Advanced spectrum more efficiently compared to using just macrocells.

Small cells may encompass , picocells, and microcells. Small-cell networks can also be realized by means of distributed radio technology using centralized baseband units and remote radio heads. Beamforming technology (focusing a radio signal on a very specific area) can further enhance or focus small cell coverage. These approaches to small cells all feature central management by mobile network operators.

Small cells provide a small radio footprint, which can range from 10 meters within urban and in-building locations to 2 km for a rural location. Picocells and microcells can also have a range of a few hundred meters to a few kilometers, but they differ from femtocells in that they do not always have self-organising and self-management capabilities.

Small cells are available for a wide range of air interfaces including GSM, CDMA2000, TD-SCDMA, W-CDMA, LTE and WiMax. In 3GPP terminology, a Home Node B (HNB) is a 3G femtocell. A Home eNode B (HeNB) is an LTE femtocell. Wi-Fi is a small cell but does not operate in licensed spectrum therefore cannot be managed as effectively as small cells utilising licensed spectrum. The detail and best practice associated with the deployment of small cells varies according to use case and radio technology employed.

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Wikipedia