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 overoptimistic 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.