**2.1. Interference constraints**

As mentioned in the Introduction, frequency reuse is a key issue in current mobile communication systems. It is well known that the co-channel interference caused by frequency reuse is the most restraining factor on the overall system capacity in wireless networks. Therefore, the main purpose is the simultaneous use of a given radio spectrum while maintaining a tolerable level of interferences. Specifically, each system cell is assigned a set of channels according to the expected traffic demand. This assignment of channels must satisfy the following constraints:


The channel assignment algorithm must also take into account the specified traffic profile (number of channels) required in each cell. These non-uniform cell demand requirements imply that those cells with a higher traffic demand will need the assignment of more channels.
