For telephone services to mobile phones, Hierarchical cell structure ("HCS")[1] used in mobile telecommunication means the splitting of cells.
This type of cell structure allows the network to effectively use the geographical area and serve an increasing population.
The micro/pico cell is allocated the radio spectrum to serve the increased population.
The mobiles in high mobility prioritise to reselect to the lower priority cells to avoid continuous reselections.
Microcells can add localized capacity within Macro cell.