An efficient delay-restricted scheduling algorithm for multi-carrier TD-HSDPA systems

Abstract

As a mainstream technology in the B3G TDD systems, TD-HSDPA (LCR TDD HSDPA, High-Speed Downlink Packet Access of Low Chip Rate TDD) adopts some key techniques to achieve high system throughput and high peak data rate, such as AMC (Adaptive Modulation and Coding) and HARQ (Hybrid Automatic Repeat reQuest). However, feedback delay is inevitable in practical TD-HSDPA systems due to the conventional scheduling mechanism, and its impact on wireless scheduling is critical. In this paper, the joint system performances of the key techniques are studied; furthermore, a new efficient scheduling algorithm is proposed. Compared to the conventional scheduling, the delay-restricted scheduling can reduce the feedback delay to improve the system capacity remarkably. Detailed network-performance results are shown from a comprehensive dynamic system-level simulator, and these presented results are obtained for a macrocellular scenario with best effort packet data services to reflect the expected improvement from introducing delay-restricted scheduling in a multi-carrier TD-HSDPA system.