A Utility-Based Downlink Radio Resource Allocation for Multiservice Cellular DS-CDMA Networks
1 Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario M5S 3G4, Canada
2 Department of Electrical and Computer Engineering, Faculty of Engineering, Tarbiat Modares University, P.O. Box 14155-4838, Tehran, Iran
3 The Broadband Communications and Wireless Systems (BCWS) Center, Department of Systems and Computer Engineering, Carleton University, Ottawa, Ontario K1S 5B6, Canada
EURASIP Journal on Wireless Communications and Networking 2007, 2007:076193 doi:10.1155/2007/76193Published: 8 March 2007
A novel framework is proposed to model downlink resource allocation problem in multiservice direct-sequence code division multiple-access (DS-CDMA) cellular networks. This framework is based on a defined utility function, which leads to utilizing the network resources in a more efficient way. This utility function quantifies the degree of utilization of resources. As a matter of fact, using the defined utility function, users' channel fluctuations and their delay constraints along with the load conditions of all BSs are all taken into consideration. Unlike previous works, we solve the problem with the general objective of maximizing the total network utility instead of maximizing the achieved utility of each base station (BS). It is shown that this problem is equivalent to finding the optimum BS assignment throughout the network, which is mapped to a multidimensional multiple-choice knapsack problem (MMKP). Since MMKP is NP-hard, a polynomial-time suboptimal algorithm is then proposed to develop an efficient base-station assignment. Simulation results indicate a significant performance improvement in terms of achieved utility and packet drop ratio.