這幾年來，通訊領域中最火熱的議題，就是正在發展中的 5G 通訊系統。由於現代人對於行動網路的需求不斷提高，6GHz 以下的頻寬資源已非常有限；而高頻段仍具有非常豐富的頻譜資源，於是各界紛紛研究往高頻段發展的可能性，毫米波也因此而成為 5G 通訊的重點發展項目。

由於毫米波的能量衰減較大，傳輸距離也相對較短，因此毫米波系統通常搭配大規模多天線與波束成形技術作為輔助，藉此抑制訊號之間的干擾，並有效提升傳輸率。本論文中，採用 MIMO OFDM 架構，並藉由升降頻器與校正機制的引入，實現毫米波波束成形的系統平台建置；標準級的毫米波儀器，造價都於千萬以上，而我們主要利用校正機制，彌補硬體上的時間延遲所造成的相位差，成功實現一套價格平易近人的毫米波波束成形系統，此處正是我們最具競爭力之處。

除了毫米波平台的實現之外，我們更利用此平台，著手 UE 的開發。由於毫米波頻帶的最大瓶頸，就是遮蔽所造成的效能驟降，因此我們藉由 UE 端的實際量測數據，觀察毫米波場景下不同架構配置的量測結果，進一步比較 UE 端的效能變化，對 UE 端規劃一套合適的毫米波配置。

In the recent years, the most discussed topic in communication area is developing 5G communication system. Due to the increasing demand for mobile networks from people in nowadays, the sources of available bandwidth below 6 GHz is very scarcity. However, there still have rich spectrum resources in high frequency, so all walks of life study the possibility of develop towards high frequency, mmWave also become as key development project for 5G communication.

Since the mmWave has a large energy attenuation and a relatively short transmission distance, the mmWave system is usually supplemented by large-scale multi-antenna and beamforming to suppress interference and increases the transmission rate effectively. In the paper, we adopt MIMO OFDM architecture and adding in the used of up/down converter and calibration to implement the millimeter-wave beamforming platform. Standard-grade millimeter-wave instruments cost more than 10 million, and we mainly use the calibration to compensate for the phase difference caused by the time delay on the hardware, and successfully implement a set of affordable millimeter-wave beamforming system. It’s our most competitive advantage.

Moreover, we use this platform to develop the design of UE. The biggest problem of mmWave is the drop of the performance because of the blockage. We can design the appropriate setting of the mmWave system on the mobile device based on the measurement result on this platform to lower the development cost and time period.

論文審定書 i
致謝 ii
摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 viii
第一章 緒論 1
1.1 研究背景與動機 1
1.2 論文安排 3
第二章 相關背景 4
2.1 多輸入多輸出 4
2.2 正交分頻多工簡介 6
2.2.1 正交分頻多工傳送接收架構 8
2.2.2 循環字首 9
2.2.3 傳輸訊框與資源架構 10
2.3 波束成形 10
2.3.1 波束成形簡介 10
2.3.2 波束追蹤簡介 15
2.3.3 波束成形原理 16
2.4 系統模型 18
第三章 毫米波量測平台原型 20
3.1 儀器簡介 20
3.2 系統架構 21
3.2.1 升降頻器簡介 21
3.3 校正機制 22
3.4 高頻波束成形系統實現 27
第四章 量測結果與分析 28
4.1 單純環境量測分析 28
4.1.1 手握模式與場景設定 28
4.1.2 不同入射角比較 30
4.1.3 不同距離比較 31
4.1.4 不同天線種類比較 32
4.2 複雜環境量測分析 33
4.2.1 長距離機殼遮蔽 33
4.2.2 長距離多障礙物 34
4.2.3 長距離手握 36
4.2.4 長距離多建築物 38
第五章 總結 40
參考文獻 41

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