Subcarriers and Bits Allocation in Multiuser Orthogonal Frequency Division Multiplexing System

In order to optimize the spectrum resource allocation in the orthogonal frequency division multiplexing system and minimize the transmitted power, this paper proposed a modified basic particle swarm optimization algorithm to allocate the subcarriers and bits of the orthogonal frequency division multiplexing system. The algorithm uses the average individual extreme value instead of individual extreme value to update the particles. Meanwhile, when the particle velocity is bigger than the maximum velocity or smaller than the minimum velocity, an average velocity is taken as the updating velocity. It not only maintains the advantage of basic particle swarm optimization, but also makes the particle acquire more information to adjust its movement. Simulation results showed that the spectrum resource allocating based on modified basic particle swarm optimization algorithm has 2~9 dB margin in the total transmitted power than the genetic algorithm, basic particle swarm optimization algorithm and method jointing basic particle swarm optimization algorithm and genetic algorithm. Copyright © 2014 IFSA Publishing, S. L.