Date Added: Nov 2011
The expansion and evolution of cellular networks over the past decades has been astounding. Networks initially designed for voice traffic have grown to accommodate increasingly high data-traffic loads. This growth has long relied on a network of macro cells to provide a good balance of wireless coverage and capacity. The fast uptake of mobile data services driven by Smartphone's, laptops, and more recently, tablets has accelerated data-traffic growth to the point that the macro cellular network is no longer sufficient to meet subscriber demand in many high-density settings all over the world. The introduction of LTE in the macro network will provide only limited and short-lived relief, as traffic is growing at a faster rate than the capacity increment it will yield.