GradCon 2013
University of Manitoba
Department of Electrical & Computer Engineering
ADVISOR: Ken Ferens, Ph.D., P.Eng.
Proceedings of the 2013 Graduate Students Conference, GRADCON 2013
Winnipeg, MB, Canada; October 18, 2013
©Copyright retained by author and collaborators
A Chaotic Genetic Algorithm for Radio Spectrum Allocation
Olawale David Jegede
Dept. Electrical & Computer Engineering
University of Manitoba
jegedeo@myumanitoba.ca
Abstract - A Chaotic Genetic Algorithm (CGA) for Cognitive Radio (CR) spectrum allocation procedure is
presented. The development of the Cognitive radio system puts emphasis on the efficient utilization of spectrum for
both primary and secondary users. Secondary users make use of the spectrum without degrading the quality of
service of the primary user(s) [1]. The CR is able to able to sense available spectrum, establish and maintain quality
of service (QoS) requirements for user’s application, meet service level agreement (SLA) and understand its own
operational capabilities such as radio parameters [2]. We assume that spectrum sensing has been done; thus a
secondary user can specify the quality of service (QoS) requirements for a particular application at any given time.
Genetic algorithm (GA) is a subset of evolutionary algorithms that models biological processes to optimize highly
complex functions. A GA allows a population composed of many individuals to evolve under specified selection
rules to a state that maximizes the “fitness” (i.e. minimize the objective function). The main advantage of using GA
over other stochastic techniques is its parallelism, which speeds up the simulation results leading to faster
convergence. However, some notable drawbacks of the traditional GA (TGA) include slow convergence and a
possibility of being stuck in local optimum solution. The TGA uses a random process to generate parameter values
for the selection, crossover and mutation processes. Random number generators are designed to result in either
uniform distributions or Gaussian distributions [3].
We conjecture that selection, crossover and mutation in genetics are driven by a random non-linear dynamics
process rather than a random process. Therefore in the spectrum allocation process, a chaotic logistic map is
incorporated into the initial population generation as well as in the crossover and mutation processes of TGA. The
properties of a chaotic system that provide additional benefits over randomly generated solutions are sensitivity to
initial conditions, topological density and topological transitivity [1]. These ensure that CGA is able to explore the
entire solution space. Introducing chaos into the whole process of a traditional genetic algorithm may help improve
convergence time and accuracy. This concept is termed Chaotic GA (CGA). Simulation was implemented in
MATLAB to compare the results obtained for CGA and TGA.
REFERENCES
1. O. Jegede, K. Ferens, W. Kinsner, "A Chaotic Genetic Algorithm for Radio Spectrum Allocation" in Proceedings of the
International Conference on Genetic and Evolutionary Methods, Las Vegas, NV USA, pp. 118-125, 2013.
2. T. Siddique and A. Azam, "Spectrum Optimization in Cognitive Radio Networks Using Genetic Algorithms," Master’s
Thesis, Blenkinge Institute of Technology, Sweden, 2010.
3. D. Cook, K. Ferens and W. Kinsner, "Application of Chaotic Simulated Annealing in the Optimization of Task
Allocation in a Multiprocessing System," IEEE International Conference on Cognitive Informatics and Cognitive
Computing, 2013.