Metro or picocells are typically deployed in public areas such as stadiums, airports or on light posts on the streets. They transmit at relatively high power and are usually deployed by the operators.
Picocells are often deployed in low density initially to fill coverage holes. In that stage, the main requirement is seamless handover with macrocells. The need for SON is limited to self-configuration until their density increases which results in lower distance and more overlap in coverage among picocells. At higher density, UltraSON™ technology features become critical to mitigate interference, as provided by the power management (PM) and resource management (RM) algorithms.
In most deployments, picocells will share the same channel with macrocells. To maximize traffic offload to the picocells, FeICIC should be supported in addition to UltraSON. FeICIC maximizes traffic offload from macros to picocells by partitioning resources between macros and picocells to expand the range of the latter.