An important part of the business case for femtocells for operators is to offload their macrocellular network, so they don’t need to invest as much in their basestations. If a large part of the network traffic is handled locally by femtocells and connected through customer’s own broadband internet, then significantly less investment will be required. Less additional radio equipment on each cellsite, less backhaul (transmission from the cellsites to the operator’s main switching centres) and potentially reducing the need for additional sites in heavily congested areas.
The premise of the vendors is that femtocells should require no radio planning. Since operators do not, by and large, know where any individual femtocell will be deployed, they cannot reconfigure their macro network to account for this. There is substantial research and trial work ongoing to reduce the impact of the femtocell on the outdoor macrocellular network. Since the signal levels are very low power and do not easily penetrate walls, little is radiated outside the premises where they are located. Some femtocells also “listen” to the external macrocellular network to pick a frequency which will cause minimum interference.