隨著第五代行動通訊系統(5G)的快速發展，越來越多嶄新的傳輸技術被提出，而通用濾波多載波系統(UFMC)擁有和正交分頻多工系統(OFDM)相似的系統架構，並且將子載波分成多個子頻帶，然後在每個子頻帶上進行濾波的設計可以降低頻譜的旁波瓣位準(sidelobe level)，避免OFDM系統的高旁波瓣位準所帶來的載波間干擾(ICI)，同時減少循環字首(Cyclic Prefix)的消耗，且和FBMC系統對每一個子載波濾波相比，大幅的減少了複雜度以及濾波器的長度所造成的成本開銷。因此，針對5G複雜的傳輸環境時，UFMC傳輸技術做為候選是具有其優勢的。
多輸入多輸出(Multi-input Multi-output, MIMO)為長期演進技術進階版(LTE-A)的主要技術規格。因此，本篇論文提出2×2空頻區塊碼(Space-Frequency Block Code, SFBC)應用於通用濾波多載波系統(SFBC-UFMC)，並且對不同的接收端進行誤碼率(BER)分析；在MIMO系統中通常會加入線性轉換(Linear Transform)來改善系統的效能，因此，本篇論文也採用不同的線性轉換技術進行分析。但是SFBC以頻域做編碼在結合線性轉換時會破壞原本傳輸訊號的順序以及架構，導致峰均值功率比(Peak-to-Average Power Ratio, PAPR)的提升。本篇論文以較低的PAPR作為需求來設計編碼方式，在模擬結果中，提出的編碼方式可以保有較低的PAPR並且在BER上可以維持相近的效能。

With the rapid development of the 5th Generation wireless systems (5G), more and more new transmission technologies have been proposed, and the Universal Filter Multi-Carrier System (UFMC) has a system architecture similar to the Orthogonal Frequency Division Multiplexing (OFDM) system and the design of divide the sub-carrier into multiple sub-bands, and then filter on each sub-band can reduce the sidelobe level of the spectrum and avoid the inter-carrier interference (ICI) caused by the high sidelobe level of the OFDM system, while reducing the consumption of the Cyclic Prefix, and greatly reducing the complexity compared to the filtering of each subcarrier by the FBMC system. Therefore, UFMC transmission technology has its advantages as a candidate for 5G complex transmission environment.
Multi-Input Multi-Output (MIMO) is the main technical specification of the Long Term Evolution Advanced (LTE-A).Therefore,in this paper 2×2 Space-Frequency Block Code (SFBC) is applied to Universal Filtered Multi-Carrier system (SFBC-UFMC), and the bit error rate (BER) analysis is performed on different receivers. In the MIMO system, Linear Transform is usually added to improve the performance of the system. Therefore, this paper also uses different linear transform techniques for analysis. However, the SFBC coding in the frequency domain will destroy the order and structure of the original transmission signal when combined with the linear transform, resulting in the increase of Peak-to-Average Power Ratio (PAPR). In this paper, the coding method is designed for lower PAPR. In the simulation results, the proposed coding method can maintain a lower PAPR and similar BER performance.

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