A robust operation of assigning frequencies to requirements in a time-division multiple-access (TDMA) [or frequency-division multiple-access (FDMA)] cellular system should cope with environmental changes such as short-term demand rises and long-term capacity expansions while always keeping the required realignment process as simple as possible. In this paper, we consider the so-called perturbation-minimizing frequency assignment problem (PMFAP), the objective of which is to assign available frequencies for newly generated requirements with the minimum change in the existing frequency assignments while meeting the interference-related constraints. For PMFAP, we propose a heuristic algorithm based on the so-called B nu-D omega rearrangement technique, which can also be applied to the classic frequency assignment problem (FAP) with a slight modification. Two kinds of computational experiments, one for each of the above two problems, are performed to demonstrate the powerful features of the proposed solution method not only in its suitability for real-world frequency management, but also in solving the FAP.