The exponential growth of mobile data traffic affects not only the capacity requirements of the mobile networks but even the expected Quality of Service. Introduction of LTE improved the situation to some extent. However as a high percent of mobile data traffic is generating from indoors, LTE at higher frequencies cannot really meet the ever increasing demand of data traffic and reasonable QoS. This Book provides an analysis of the network throughput with LTE technology that includes macro and indoor traffic distribution pattern using system level simulation environment. Simulation results show that with increasing percentage of indoor traffic, the throughput of macro network decreases significantly. Lately, two possible solutions emerged to offload the indoor traffic by WiFi or Femtocell. A brief overview of the two solutions is presented and the more promising, femtocells are further evaluated. The analysis shows the increase in macro network throughput by offloading the traffic via femtocells. Deployment of Femtocells can surely be of great interest to both users and operators providing users with good QoS and operators with low CapEx and OpEx while providing the high revenue.