An Efficient Downlink Mapping Algorithm for AMC Mode in WiMAX Systems

• Main Authors: Huang Qi-Quan, 黃啟全
• Other Authors: 李程輝
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/27315457200991505715

碩士 === 國立交通大學 === 電信工程研究所 === 100 === This thesis proposes an efficient downlink resource allocation scheme for Orthogonal Frequency-Division Multiple Access (OFDMA)-based WiMAX systems using the Adaptive Modulation and Coding (AMC) mode operation. Given a set of user requests, the proposed algorithm determines the modulation scheme and allocates a two-dimensional (time and frequency) burst to each user. It is known that finding the optimal solution for such a resource allocation problem is NP-complete. To reduce the computation complexity, this thesis proposes a heuristic solution. When compared with the Efficient Downlink Bandwidth Allocation (EDBA) algorithm,the proposed scheme achieves higher channel utilization and system throughput with a similar execution time. Simulation results show that the average channel utilization of the proposed scheme is approximately75%–85%,while that of EDBA is approximately 60%–70%.