Complexity Analysis of a Heuristic Method for Fixed-Frequency Assignment Including Adjacent Channel Interference

In this paper, we extend an existing heuristic algorithm for fixed-frequency assignment in cellular communication networks in order to account for the effects of adjacent channel interference (ACI). Our algorithm utilizes estimations of carrier-to-interference ratio instead of binary channel separation constraints. The extended algorithm avoids over-optimistic frequency assignments that do not guarantee interference-free operation environments. Its cost is the increased computational complexity. We estimate the upper bound of the algorithm´s complexity when ACI is taken into account. Simulations demonstrate that despite the theoretical high increase in complexity, the algorithm is suitable even for a quasi-dynamic frequency assignment scheme in practical situations. The algorithm enhances the spectrum utilization in cellular networks while reducing harmful interference.