在第四代行動通訊(the 4th Generation of mobile communication system,4G)中，通訊標準為正交分頻多工技術為主，雖然它憑藉著有效的對抗頻率選擇性衰減通道、抗碼間干擾能力強、實現簡單等諸多優點，但缺點為高頻外溢出與高峰均值功率比，這些缺點與第五代的行動通訊系統(the 5th Generation of mobile communication system,5G)未來目標所設定的條件不符。
隨著物聯網的興起，下一代移動通信系統將面臨新的挑戰，不僅僅是增加吞吐量，觸覺互聯網要求低延遲，處理大覆蓋區域需要穩健性。除此之外，下一代通訊系統的任何波形都需要與多輸入多輸出(Multi-Input Multi-Ouput ,MIMO)兼容。廣義分頻多工(Generalized Frequency Division Multiplexing,GFDM)是一種可以靈活應對未來網路即將到來的需求的候選者，它有著低頻外溢出和低峰均值功率比(Peak to Average Power Ratio,PAPR)的特性，並且能有效的利用電視白空間，讓現今零散的頻段能有效的被利用。
在本篇論文中，我們在時間反轉空時區塊碼(TR-STBC)中分別使用了多種解碼方法來進行效能分析，同時也使用了多種Transform進而討論GFDM的PAPR、位元錯誤率(Bit error rate,BER)同時也討論了各個解碼方法之複雜度(complexity)。
BER效能模擬將會在GFDM系統之不同濾波器、通道模型、調變方法的環境下進行，分析每一種方法在不同的情況下會有甚麼影響。
關鍵字：廣義分頻多工、空時編碼、線性轉換、複雜度、峰均值功率比、解碼器

In the 4th Generation of mobile communication system (4G), the communication standard is dominated by orthogonal frequency division multiplexing technology, although it relies on effective frequency selective attenuation channels, strong resistance to inter-code interference, achieve simplicity and many other advantages.However, the disadvantage is the high-frequency external overflow and the peak-to-average power ratio. These shortcomings are inconsistent with the conditions set by the 5th Generation of mobile communication system (5G).
With the rise of the Internet of Things, next-generation mobile communication systems will face new challenges, not only to increase throughput, but also to require low latency for the Internet, and to handle robustness in handling large coverage areas. In addition, any waveform of the next generation communication system needs to be compatible with Multi-Input Multi-Ouput (MIMO). Generalized Frequency Division Multiplexing (GFDM) is a candidate that can flexibly respond to the upcoming needs of future networks. It has low-frequency out-of-band and low-to-peak power ratio (PAPR). Features, and can effectively use the TV white space, so that today's scattered frequency bands can be effectively utilized.
In this paper, we use a variety of decoding methods for performance analysis in time-reversed space-time block codes (TR-STBC). At the same time, a variety of Transforms are used to discuss the PAPR and Bit error rate (BER) of GFDM and also discuss the complexity of each decoding method. The BER performance simulation will be performed in different filter, channel model, and modulation method environments of the GFDM system to analyze the impact of each method in different situations.
Keyword：GFDM、STBC、Linear Transform、Complexity、PAPR、Decoder

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