基於感知無線電技術之合作式通訊系統之頻譜資源分配

Resource Allocation in Cognitive Radio Assisted Cooperation for Downlink OFDMA Systems

李昱昇(Yu-Sheng Li)

指導教授 ： 譚旦旭 ； 黃永發

國立臺北科技大學/電資學院/電機工程系研究所/碩士(2013年)

https://doi.org/10.6841/NTUT.2013.00382

摘要

為使無線通訊頻帶有效運用，感知無線電(Cognitive Radio, CR)技術可用來讓非授權用戶(Unauthorized Users)借用原授權用戶(Authorized Users)頻帶區段，在不干擾主要用戶(原被授權用戶)的條件下，提升頻帶使用效率(Bandwidth Efficiency)，而改善目前頻帶資源不足的問題。此外，應用中繼站(Relay Stations, RSs)達成之合作式通訊(Cooperative Communications)可改善4G行動通訊系統中的下鏈(Downlink)傳輸效能。因此，本論文在已知可用通道(Available Channels)之條件下，結合中繼站之合作式通訊與感知無線電之通道分配(Channel Assignment)技術，以改善系統之頻譜使用效能。模擬結果顯示，本論文提出之滿足度分配法，除了系統傳輸量(Throughput)可達成最佳效能外，公平指標(Fairness Index)與滿足度(Utility)等效能亦均獲相當顯著的改善。

關鍵字

感知無線電 ； 合作式通訊 ； 系統傳輸量 ； 頻帶分配 ； 中繼站 ； 公平指標

並列摘要

Cognitive radio (CR) allows unauthorized users to access authorized band without interfering the authorized user, thereby improving the bandwidth efficiency. In addition, cooperative communications with relay stations (RSs) can be used to improve throughput performance of 4G downlink network. In this study a cognitive radio assisted cooperation (CRAC), which combines advantages of CR and cooperative communications with RSs, is considered for resources allocation in the downlink orthogonal frequency division multiple access (OFDMA) networks. Two adaptive resource allocation algorithms are presented and experimental results demonstrate that the proposed algorithms can not only enhance throughput, but also improve fairness and utility of users assuming available channels are known by base station.

並列關鍵字

Cognitive Radio (CR) ； Cooperative Communications ； Throughput ； Channel Assignment ； Relay Station(RS) ； Fairness Index

參考文獻

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