AT&T recently reported that it experienced wireless data growth of more than 2000 percent between 2007 and 2010. Alcatel-Lucent predicts that mobile data will increase 30-fold between 2010 and 2015.
Up to this point, mobile service providers have used two primary approaches to providing more bandwidth: increase the backhaul and capacity of macrocell sites, and offload demand to Wi-Fi networks. Now many suggest a third approach, use of “metro cells,” also is needed.
Metro cells, the latest evolution in small cells, are based on the same low-cost femtocell technology that has been successfully used in home and enterprise cells. With higher processing and transmit power, the first generation of metro cells is engineered to serve from 16 to 32 users and provide a coverage range from less than 100 meters in dense urban locations to several hundred meters in rural environments.
However, unlike home and enterprise cells, metro cells are owned and managed by a service providers and typically used in public or open access areas to augment the capacity or coverage of a larger macro network. All of that has backhaul implications, of course.
Juniper Research forecasts that by 2015, 63 percent of mobile data traffic will be offloaded to fixed networks, with small cells accounting for a steadily increasing proportion of the total offloaded traffic.
The metro cell approach trades off capital investment in the macrocells for investment in traditional macrocells. The backhaul bandwidth implications in many cases will trade off optical or microwave backhaul for use of fixed network facilities. In some tests, high-speed DSL circuits have proven suitable for backhaul purposes.
Alcatel-Lucent argues the capital savings can amount to 55 percent when using a metro cell approach, in dense urban deployments. Read the paper here.