Femtocells are low-power wireless access points – originally called Access Point Base Stations – that operate in licensed spectrum to connect standard mobile devices to a mobile operator’s network using the customer’s DSL or cable broadband connection. A femtocell is a scalable, multi-channel, two-way communications device that incorporates key elements of a mobile radio access network into a compact device – about the size of the typical desktop Wi-Fi router – and can be deployed in a home or office.
Demands for wireless data services are showing rapid growth due to evolved networks for high speed connectivity, wide-scale deployment, flat-rate pricing plans and Internet-friendly devices (smartphones). As consumers rely heavily, and often-times exclusively, on mobile devices for their communications needs, wireless operators have begun turning to alternative means in which to improve cellular coverage in difficult to reach locations as well of off-load traffic from their wireless networks. Many operators, including GSM-HSPA, and CDMA/EV-DO operators, are trialing or planning to deploy femtocells to better support residential and small/home office applications. Vodaphone UK was the first operator to launch a commercial femtocell service in Europe (July 2009), with AT&T(2H 2009) and Verizon (early 2010) among the operators who also launched commercial femtocell offerings.
The femtocell access point is connected to a high-speed Internet or other IP connection to interface with the GSM or UMTS core packet-switched and circuit-switched networks. Femtocells work with standard devices that are compliant with existing 2G and 3G air interface technologies. This ensures seamless service and good interoperability with existing networks and avoids the need for specifically adapted handsets.
From a competitive perspective, femtocells can help mobile operators seize residential minutes from fixed providers, increase market share and respond to emerging VoIP and Wi-Fi offerings.
From a quality of service perspective, femtocells will improve the user experience in the home. This is essential for reducing churn and providing new revenues.
Some capacity offload is anticipated from the use of femtocells but those benefits have not yet been quantified.
The femtocell solution typically employs power and backhaul via the user’s existing resources (for example, DSL). It also enables capacity equivalent to a full 3G network sector at very low transmit powers, dramatically increasing battery life of existing phones, without needing to introduce Wi-Fi enabled handsets.
Potential challenges to the deployment of femtocells are the reliance on the consumer to support of backhaul capabilities and the possibility of interference caused by the close placement of multiple femtocell devices.