Optimal code assignment and call admission control for OVDF-CDMA systems constrained by blocking probabilities

Abstract

The tradeoff between the throughput and the blocking probability of various code assignment schemes for OVSF-CDMA (orthogonal variable spreading factor CDMA) systems is investigated, and the optimal fixed and dynamic code assignment schemes that maximize the average data throughput under a blocking probability constraint are proposed. The optimal schemes are obtained using constrained optimization through the Markov decision process and linear programming. The performance of each scheme is numerically evaluated. Numerical results demonstrate that the proposed new schemes can achieve a satisfactory balance between the average throughput and the blocking probability.