An heuristic search technique for fixed frequency assignment in non-homogeneous demand systems

Abstract

In this paper, an heuristic algorithm is applied to solve the problem of frequency reuse in cellular radiocommunication systems, where the main aim is to obtain a channel assignment free of interferences such that the resulting bandwidth is close to the minimum theoretical channel span required. Specifically, a genetic algorithm (GA) whose probabilities of mutation and crossover are on-line adjusted based on the diversity of the population is presented. This diversity is estimated by means of analyzing the individuals’ fitness entropy. The resulting algorithm obtains accurate solutions, thus offering an interesting alternative to other global search techniques, such as simulated annealing, tabu search and neural networks, as well as to standard GAs. A complete selection of the most well-known benchmark instances has been used in order to evaluate the performance of the proposed procedure. Numerical simulations show that optimal bandwidth solutions are achieved within a reasonable computation time for all the problem instances tested.