the entire network coverage area is divided into cells based on the principle of frequency reuse
a cell = basic geographical unit of a cellular network; is the area around an antenna where a specific frequency range is used; is represented graphically as a hexagonal shape, but in reality it is irregular in shape
when a subscriber moves to another cell, the antenna of the new cell takes over the signal transmission
a cluster is a group of adiacent cells, usually 7 cells; no frequency reuse is done within a cluster
the frequency spectrum is divided into subbands and each subband is used within one cell of the cluster
in heavy traffic zones cells are smaller, while in isolated zones cells are larger