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Design and Analysis of Time-Based Code Allocation Schemes in W-CDMA Systems
November/December 2005 (vol. 4 no. 6)
pp. 604-615
Efficient resource allocation for requests is an important issue in the radio resource management. In the third generation mobile communication systems, Orthogonal Variable Spreading Factor (OVSF) codes are used for spreading codes. In this paper, we consider the OVSF code allocation problem for supporting real-time services in which the service time of a request can be obtained a priori. The impact of the remaining time factor on the OVSF code allocation in W-CDMA systems is investigated. Two time-based allocation schemes are proposed for code assignment and reassignment. This paper represents the first attempt on addressing the remaining time impact on the OVSF code allocation. Simulation results show that the time-based allocation schemes have better performance on reducing the blocking probability and the reassignment cost.

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Index Terms:
Index Terms- Code allocation, OVSF, radio resource management, real-time services, W-CDMA.
Citation:
Sheng-Tzong Cheng, Ming-Tzung Hsieh, "Design and Analysis of Time-Based Code Allocation Schemes in W-CDMA Systems," IEEE Transactions on Mobile Computing, vol. 4, no. 6, pp. 604-615, Nov.-Dec. 2005, doi:10.1109/TMC.2005.86
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