A minimum-Bandwidth Guaranteed Scheduling Algorithm for Data Services in CDMA/HDR System

CDMA/HDR system is designed to provide High Data Rate services in the cellular networks compatible with IS-95B CDMA network. It uses a PF(Proportional Fairness) scheduler that improves total throughput by using multi-user diversity in a forward link while supporting user’s average throughput proportional to channel conditions. Therefore, PFS does not guarantee the minimum data rate to the users with poor channel conditions. We propose a new scheduling algorithm, which bounds the throughput ratio(_RminRmax) between the best-channel user and the worst-channel user and maximizes the total throughput. Thus, it can guarantees minimum bandwidth by adapting the throughput ratio(_RminRmax). Furthermore, if the user data in the queue is less than the accommodation size of the assigned slot, there will be a loss of efficiency. We add a function to the scheduler to protect the system from this performance degradation.