近年來由於通訊系統的發展迅速，5G與物聯網的應用越來越多，對於終端設備的需求也逐年上升。因此，對於終端設備電池的續航力要求、對於頻譜效益的要求以及多用戶的需求也逐漸被重視，基於以上情況，索引調變在這樣的條件下便是一種很好的選擇。由於索引調變的原理所限制，這項技術在使用較大的QAM數，或是增加每個索引調變分組的子載波時，會導致頻譜效益下降許多，因此不適合使用在某些場景。
本篇論文提出了一個正交分頻多工下的雙模態索引調變系統，透過將一個分組內子載波數量較少的索引調變訊號結合到一個分組內子載波數量大的IM訊號中。本系統可以在不犧牲能源效益的情況下，也能夠提升頻譜效益，並且可以增加終端用戶的服務數量。另外，也對本系統提出了基於強制歸類的檢測器設計方法，並比較了不同檢測器的複雜度，以及在最後透過系統模擬AWGN與瑞利通道中檢測器的效能結果。最後也提供了未來可以改良本系統的可行辦法，以供後續研究發展。

In recent years, due to the rapid development of communication systems, the application of 5G and the Internet of Things is increasing, and the demand for terminal equipment is also increasing year by year. As a result, the requirements for battery life of terminal equipment, spectral efficiency, and the need for multi-users have been gradually emphasized. Based on the above, Index Modulation (IM) is a good choice under such conditions. Due to the limitation of the IM principle, this technology is not suitable for certain scenarios because it will result in much lower spectral efficiency when using larger QAM size or increasing the number of subcarriers in each IM group.
This paper proposes a Dual-Mode OFDM Index Modulation system by combining an IM signal with a small number of subcarriers in one subgroup into an IM signal with a large number of subcarriers in one subgroup. This system can improve spectral efficiency without sacrificing energy efficiency and can increase the number of end-user services. In addition, a detector design method based on forced categorization is proposed, the complexity of different detectors is compared, and the performance results of detectors in AWGN and Rayleigh Channel are simulated by the system. Finally, the feasible ways to improve the system in the future are also provided for further research and development.

摘要 i
Abstract ii
致謝 iii
圖目錄 iv
表目錄 vii
第一章 簡介 1
1.1 緒論 1
1.2 研究動機與目的 4
1.3 論文架構 6
第二章 訊號原理簡介 7
2.1 正交分頻多工 ( Orthogonal Frequency Division Multiplexing ) 7
2.2 OFDM發射機與接收機 8
2.3 索引調變簡介 (Index Modulation) 10
2.4 OFDM-IM原理 11
2.5 OFDM-IM 索引位元映射方法 13
2.6 OFDM-IM的發射機與接收機 16
第三章 雙模態OFDM索引調變系統 17
3.1 雙模態OFDM索引調變系統簡介 17
3.2 雙模態OFDM索引調變系統模型與星座點設計 18
3.3 雙模態OFDM索引調變系統調變設計 20
3.4 雙模態OFDM索引調變系統接收機檢測器 22
3.5 雙模態OFDM索引調變系統檢測器複雜度比較 31
3.6 頻譜效益分析 34
第四章 雙模態OFDM索引調變系統模擬結果 36
4.1 模擬系統架構 36
4.2 AWGN通道模擬結果 39
4.3 Rayleigh Fading模擬結果 58
第五章 結論與未來工作 68
參考文獻 69

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