An overview of the femtocell concept

The femtocell concept aims to combine fixed-line broadband access with cellular telephony using the deployment of ultra-low-cost, low-power third generation (3G) base stations in the subscribers' homes or premises. It enables operators to address new markets and introduce new high-speed services and disruptive pricing strategies to capture wireline voice minutes and to grow revenues. One of the main design challenges of the femtocell is that the hierarchical architecture and manual cell planning processes used in macrocell networks do not scale to support millions of femtocells. In this paper, a user-deployed femtocell solution based on the base station router (BSR) flat Internet Protocol (IP) cellular architecture is presented that addresses these problems, and several aspects of the proposed solution are discussed. The overall concept and key requirements are presented in detail. The auto-configuration and self-optimization process from purchase by the end user to the integration into an existing macrocellular network is described. Then the theoretical performance of a co-channel femtocell deployment is analyzed and its impact on the macrocell underlay is assessed. Finally, a financial analysis of a femtocellular home base station deployment in a macrocellular network is presented. It is shown that in urban areas, the deployment of publicly accessible home base stations with slightly increased coverage can significantly reduce the operator's annual network costs (up to 70 percent in the investigated scenario) compared to a pure macrocellular network.