OFDMA收發機實體層設計與多節點網路通訊協定之軟體無線電平台驗證

OFDMA Physical Layer Transceiver Design and Multi-Node Network Protocol Implementation for SDR Platform

詹翔群(Shiang-Chiun Jan)

指導教授 ： 鄧俊宏

元智大學/電機通訊學院/通訊工程學系/碩士(2012年)

https://doi.org/10.6838/YZU.2012.00199

摘要

為了達到高頻譜使用之效益，吾人提出一應用在OFDMA上鏈系統中之收發機設計，並且將各使用者之載波頻率偏移(CFO)、符元時間偏移(STO)、以及通道響應(CIR)等列入估計之考量，將此三種可能造成多重存取干擾(MAI)之變數一一估測，再使用平行干擾消除(PIC)與疊代消去法(Iteration)來改善其性能，並將訊號與雜訊子空間演算法應用於本系統中，最後將利用Nelder-Mead 所提出之搜尋法則來提升多種變數大量搜尋之搜尋效益。於本論文所提出之方法中不但可以消除OFDMA上鏈系統中多用戶之干擾，並且能夠將載波頻率偏移、符元時間偏移、通道響應等做高效率之聯合估計(Joint Estimation)。最後將由模擬結果呈現吾人所提出之演算法之性能，有著比傳統投影法較佳之性能與搜尋效益。接續將應用軟體無線電(SDR)之概念與所提出之時間估計、頻率估計以及通道估計等法則，發展多網多節點雙向通訊收發機設計，並提出在網路層之協定法則，完成多網多節點之收發機平台發展與驗證。最後將由最後將由電腦模擬以及所發展之軟體無線電平台驗證吾人之成果。

關鍵字

正交分頻多工 ； 雙向通訊 ； 正交分頻多工存取 ； 軟體無線電 ； 封包檢測 ； 平行干擾消除 ； 聯合估計 ； 搜尋法 ； 多網多節點 ； 協力通訊

並列摘要

To achieve high spectrum efficiency, we propose a transceiver design for OFDMA uplink system. Considering each user with carrier frequency offset (CFO), symbol timing offset (STO) and channel impulse response (CIR) effects, these effects will cause multiple access interference (MAI). Then, using the parallel interference cancellation (PIC) and iteration method to improve its performance, and we apply the signal and noise subspace algorithms to enhance the system performance. Next, we use the Nelder-Mead search method to improve the multiple variables search efficiency. The proposed joint estimation method not only can eliminate multi-user interference in the OFDMA uplink system, and achieve high efficiency performance. Simulation results show that the proposed methods can provide better performance than the traditional projection method and get more search efficiency. Next, we apply the software define radio platform to realize the proposed transceiver design methods with protocol algorithms for the multi-network and multi-node bidirectional communication systems. Finally, performances of the proposed methods are evaluated by computer simulation and SDR platform implementation, to confirm their efficiency in the multiuser interference environment.

並列關鍵字

OFDM ； OFDMA ； SDR ； Packet Detection ； PIC ； joint estimation ； search method ； Multi-node Multi-net ； cooperation communication ； bidirectional communication

參考文獻

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