Perturbation-minimizing frequency assignment in a changing TDMA/FDMA cellular environment

A robust operation of assigning frequencies to requirements in a time-divis ion multiple-access (TDMA) [or frequency-division multiple-access (FDMA)] c ellular system should cope with environmental changes such as short-term de mand rises and long-term capacity expansions while always keeping the requi red realignment process as simple as possible. In this paper, we consider t he so-called perturbation-minimizing frequency assignment problem (PMFAP), the objective of which is to assign available frequencies for newly generat ed requirements with the minimum change in the existing frequency assignmen ts while meeting the interference-related constraints. For PMFAP, we propos e a heuristic algorithm based on the so-called B nu-D omega rearrangement t echnique, which can also be applied to the classic frequency assignment pro blem (FAP) with a slight modification. Two kinds of computational experimen ts, one for each of the above two problems, are performed to demonstrate th e powerful features of the proposed solution method not only in its suitabi lity for real-world frequency management, but also in solving the FAP.