‘Small cells’ is the term used for operator-controlled, low-powered radio access nodes, including equipment that operators both within licensed spectrum and unlicensed carrier-grade WiFi.
Whereas a base station has a standard range of up to 35 kilometres (around 22 miles), typically, small cells have a range from 10 to several hundred meters.
Types of small cells include femtocells, picocells and microcells – broadly increasing in size from femtocells which are the smallest, to microcells which are the largest.
Femtocells are small, low-powered cellular base stations that are used predominantly within home and small businesses.
A femtocell is able to connect to a service providers network via broadband to deliver connectivity to mobile devices. They can be configured in a number of ways to suit the environment they are serving. If programmed for a home environment, a typical femtocell could support four to eight active mobile phones or eight to 16 if used in an office or enterprise setting.
Benefits of femtocells
In simple terms, picocells are different from femtocells because they are more closely managed by the network operator who also pay for site rental and transmission back the core network.
Picocells are small cellular base stations with a larger coverage area than femtocells. They are designed to provide coverage for areas such as offices, shopping malls, stadiums or train stations that have dense phone usage.
They are often used to provide the capacity and in-building penetration needed for highly populated, urban areas; taking load off the main infrastructure (the wider-ranging base stations) by adding a layer of microcells.
Microcells are very similar to picocells and it can be difficult to easily distinguish their immediate differences, but their coverage area is the prime variance.
Microcells can cover areas less than a mile in diameter and use power control to limit the radius. Microcells can be deployed temporarily in anticipation of high-traffic within a limited area, such as a sporting event, but are also installed as a permanent feature of mobile cellular networks.
All three types of cell operate in a very similar way, and are managed and configured by the mobile network operator.
Each cell is configured with neighbour lists, so that mobile phones can switch over to an appropriate nearby cell and continue their conversation without interruption.
Macrocells are cells used to provide radio coverage served by a high power cellular base station. Generally, they provide the largest coverage of cells used in telecoms. They are mounted on ground-based masts, rooftops and other existing structures, usually always at a height that provides a clear view of the surrounding area.
You can read more about ‘small cells’ in our article: What is Small Cell Technology?