基於多目標最佳化設計上行與下行多載波分碼多工接取系統之序列

Uplink and Downlink MC-CDMA Sequences Design with Multiobjective Optimization

黃淳飛(Chun-Fei Huang)

指導教授 ： 李彥文

國立暨南國際大學/科技學院/通訊工程研究所/碩士(2011年)

摘要

在多載波分碼多工接取（Multi-Carrier Code Division Multiple Access，MC-CDMA）系統中，不同的使用者會各自使用不同的展延序列（Spreading Sequence）來辨別各自傳送的資料。而在上行（Uplink）與下行（Downlink）MC-CDMA系統中，使用不一樣的展延序列對於系統的多重存取干擾（Multiple Access Interference，MAI）以及最大峰值對均值功率比（Peak-to-Average Power Ratio，PAPR）會有著不同的影響。本篇論文利用複數展延序列（Complex Spreading Sequence）並配合多目標演化式演算法（Multiobjecctive Evolutionary Algorithm，MOEA）中的NSGA-II同時考慮多重存取干擾和峰值對均值功率比對系統的影響來設計展延序列，利用設計出來的展延序列同時降低這兩項對於系統的影響，進而提昇系統的表現。

關鍵字

展延序列 ； 多目標演化式演算法 ； NSGA-II

並列摘要

In multicarrier code division multiple access (MC-CDMA) systems, different users employ different spreading sequences to distinguish their transmitted data. In the uplink and downlink of MC-CDMA systems, the multiple access interference (MAI) resistance capability and peak-to-average power ratio (PAPR) value are largely affected by the spreading sequences used. In this thesis, we use NSGA-II from Multiobjecctive evolutionary algorithm (MOEA) to design the complex spreading sequences taking into account both the MAI and PAPR factors. These resultant spreading sequences can be shown to reduce the impact of MAI and PAPR value, and thus enhance the system performance.

並列關鍵字

spreading sequence ； MOEA ； NSGA-II

參考文獻

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