Frequency reuse or frequency planning: The design process of selecting and allocating channel groups for all of the cellular base station within a system is called frequency reuse or frequency planning. Frequency re-use means that two radio channels within the same network can use exactly the same pair of frequencies, provided that there is a sufficient geographical distance (the frequency reuse distance) between them so they will not interfere with each other. The tighter the frequency re-use plan, the greater the capacity potential of the network.

S: Total no of channels available for use
K: A group of channels allocated for each cell
N: No. of cells in which S channels are divided
Total no. of available radio channels, S = KN
The N cells which collectively use the complete set of available frequencies is called a cluster. If a cluster is replicated M times within the system, the total no. of duplex channels C can be used as a measure of capacity and is given by
C = MKN = MS

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