f WIMAX since the same bandwidth is used as in the macro network. WFAP can also provide areal6 capacity gain (up to 300 times in dense deployments). Femto-to-Femto interference can become an issue for indoor coverage when private WFAPs are densely deployed due to increasing co-channel interference. The coverage can also be reduced due to high WFAP transmission power (20 dBm). WiMAX Forum's Network Working Group has defined multiple types of implementation profiles for the R6 (base station and ASN Gateway) interface namely A, B, and C. Each of these profiles differs in the capability set that each network elements implement. An equivalent profile for Femtocell is not yet defined by WiMAX Forum. In Profile A, radio resource management (RRM) functionality resides in the ASN-GW that results in slowing the handoff process while in Profile C RRM reside in the BTS that results in faster handover. On the other hand, Profile B does not mandate the implementation of 6 Areal Capacity Gain = (System capacity with WFAP deployed)/(System capacity without WASP). IEEE WiMAX ASN GW ASN GW DSL Network ((o)) ((0)) WFAPs @ Home/Office/Public Macro WiMAX Base Stations Figure 4.14 WiMAX with WFAP an R6 interface at all SO the effects on handoff are dependent on the proprietary implementation of the BTS. In June 2009, Femtocell Forum and WiMAX Forum agreed to collaborate on the development of WFAP. The key areas or challenges for defining a new profile or specification for Femtocell deployments includes interference management, spectrum management, form factor, mobility, handovers, security, end-to-end QoS and network management. The specifications will also support emergency services, lawful intercept, and location-based services. 4.5 Performance The performance aspects of Mobile WiMAX (802.16e) are presented in this section. 4.5.1 Field Testing We conducted WiMAX (802.16e) field trials to gain insights into the technology and in product offerings from different solution vendors. The tests were conducted to measure user data throughpu