Femtocells are low-power, low cost, backward compatible and portable wireless access points that operate in licensed spectrum to connect standard mobile devices to a mobile operator's network using residential DSL or cable broadband connections. Femtocells are taken as a promising option today by mobile operators to improve coverage and provide high-data-rate services in a low cost manner. Femtocells are installed at locations where users are experiencing unsatisfactory radio coverage or they require high-data-rate. There are many technical challenges for femtocells like interference from macro cells, quality of service, power control, location management, automatic system selection, security, scalability, active macro-femto handoff, activation and management.