Proper frequency planning is essential in the development of a quality cellular system. Due to the limited amount of available RF spectrum, the scarcity of channels available to each operator, and the fact that most available frequencies are non-contiguous for most operators, frequencies must be reused throughout the system to increase network capacity. The frequencies are assigned such that there is minimal cochannel and adjacent channel interference between sites. Frequency reuse is based on hexagonal cell groupings called clusters. The size of the cluster will determine how the cluster is repeated throughout the network, i.e. the reuse pattern. The frequency reuse patterns are designated as N/F. Where N is the number of cell sites in a cluster and F is the number of frequency groups within a cluster. Ericsson uses 7/21 and 4/12 reuse patterns. The cluster patterns In a 7/21 plan, there are 7 cell sites (A, B, . . . , G) and 21 frequency groups (A1, A2, A3, . . . , G1, G2,...
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