s. Femtocells are scalable, multi-channel, two-way commu- nication devices extending a typical base station by incorporating all of the major components of the telecommunications infrastructure. An important enabler of the femtocell concept is the rapid proliferation of DSL or cable-based broadband access in developed nations which in the femtocell concept provides the backhaul connectivity towards the mobile network. On the other hand the absence of a reliable DSL solution in many developing nations could become a shop stopper for the growth of femtocells. While the femto concept could be applied to any cellular technology, the industry is mainly focusing on 3G femtocell. Recently, there has been some news on WiMAX femtocells development as well. WiMAX femto- cells can offer a number of benefits to an operator namely zero cell site acquisition cost, lower cost to maintain transport network, offloaded macro cell sites, increased network coverage and improved customer satisfaction. These benefits are passed onto the end users through attractive mobile service plans, innovative data services, improved indoor coverage, high performance data services, improved multimedia experience, better voice quality, and reduced service usage cost. 11.9.2 Device Convergence To enable FMC we need devices that can operate in multiple networks. Some key attributes of such multimode devices are [22]: ASICs: These devices which can work in more than one radio technology are mandatory for FMC. These devices need multi-access ASICs to operate in various networks seamlessly allowing access to personalize services anywhere, anytime. Phones with WLAN and WPAN: Mobile phones are also being equipped with various short-range technologies including infrared, WLAN, UWB, Bluetooth, RFID and NFC (near far communications). These technologies enable the phone to become a personal data hub interacting with fixed networks in numerous ways. For example, users can buy tickets at the train station or upload movies to their flat screen TV with their mult