A dynamic resource allocation method for HSDPA in WCDMA system

Abstract

HSDPA (high-speed downlink packet access) users are not only time multiplexing in a given channelisation code but also code multiplexing during a given TTI (time transmission interval). The fast scheduling technology in HSDPA should provide a flexible method to allocate both the time domain and code domain resources to all users. Conventional scheduling methods, C/I (maximum carrier/interference ratio), PF (proportional fairness) and RR (round robin), only permit a single user to transmit per TTI, which cannot effectively use the code resources when the channel condition of the selected user is bad. A dynamic fast scheduling (DFS) method is proposed. Instead of serving only one user at each TTI, it selects multiple users to share the code domain resources at each TTI. Both the instantaneous channel condition and average throughput of each user are the scheduling criteria, and, therefore, the served users at each TTI dynamically change accordingly. The simulation results show that the proposed scheduling method increases the overall cell throughput and, at the same time, has quite a good fairness performance.