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(max Rmin ) 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(max Rmin ). 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.