與傳統的通訊方法相比，索引調變是一個通過將傳送中可用的介質或資源利用其可選擇不同的使用方式來傳送額外附加的數據位元，現已有許多索引調變的技術被開發出還應付5G及未來充滿挑戰性和多樣化需求，但近年來關於用於頻域上的索引調變研究中都沒有考量在毫米波(mmWave)環境下傳送訊號，然而在5G通訊對於傳輸速率以及行動頻寬的高要求下，毫米波(頻率範圍為30GHz 到 300GHz的電磁波)是有巨大潛力的頻段，然而相較於過去所使用的商用頻段(6GHz以下)，毫米波由水氣、氧氣吸收所造成的傳輸損耗更加嚴重，造成覆蓋範圍小、穿透性差等等缺陷，使它實施上有些困難，而解決此問題的方法之一便是使用波束成型(Beamforming)技術再配合上大規模的天線陣列就能夠有效地達成能量集中的效果。而波束成型技術根據架構上的不同可以分為三種，分別為類比波束成型(Analog beamforming)、數位波束成型(Digital beamforming)、混和波束成形(Hybrid beamforming)，但綜合考量效能以及實施上的可行性來說，混和波束成型是最佳的方案。
基於上述原因，本論文提出將現有與本論文提出的頻域索引調變結合寬頻混合波束成形，分別為HB-OFDM-IM、HB-OFDM-GIM以及HB-HSNM-GIM，探討在結合混合波束成形後是否依舊能夠維持較好的BER性能，以及比較各方案的Achievable rate。

Compared with the traditional communication method, index modulation is a method transmitting additional data bits by using the available media or resources in different ways. There are many technologies for index modulation have been developed to meet the challenging and diverse needs of 5G and the future．However, in recent years, the research on index modulation in the frequency domain has not considered transmitting signals in the mmWave environment.
Because of the high requirements of 5G communication for transmission rate and mobile bandwidth, millimeter wave is being a key technology. Unfortunately, compared with the commercial frequency bands used in the past, the transmission loss of millimeter waves caused by water vapor and oxygen absorption is more serious, resulting in defects such as small coverage and poor penetration, making it difficult to implement.
One of the ways to solve this problem is to use beamforming technology combined with a large-scale antenna array to effectively achieve the effect of energy concentration. The beamforming technology can be divided into three types according to different architectures, namely Analog beamforming, Digital beamforming, and Hybrid beamforming. However, considering the performance and feasibility of implementation, hybrid beamforming is the best solution.
Based on the above reasons, this paper proposes to combine the existing and proposed index modulation with hybrid beamforming, namely HB-OFDM-IM, HB-OFDM-GIM and HB-HSNM-GIM, to explore whether the hybrid beamforming can be combined with hybrid beamforming ,and it can still maintain good BER performance.

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