This paper investigates the non-convexity of utility-based resource allocation problems in orthogonal frequency division multiple access (OFDMA) networks with heterogeneous traffic classes. Efficient transmission in OFDMA networks requires optimal resource allocation to users based on their current channel states. Also, utility-based resource allocation improves the network resource utilization and application level quality of service (QoS) provisioning. However, a major difficulty in using utility-based OFDMA resource allocation schemes is the non-convexity of corresponding optimization problem. In this paper, a continuous optimization technique is proposed to treat the non-convexity. The approach is based on a combination of penalty function methods and interior point methods. Numerical results demonstrate that the proposed approach solves the problem within limited time, and the solutions are close to near optimal solutions obtained by the search algorithm.
Published in:
Communications, 2009. ICC '09. IEEE International Conference on
Date of Conference: 14-18 June 2009