通訊世代約每十年更迭一次。2020年，5G通訊成功推入人們的生活。為了預計在2030推行的下一世代的6G通訊，許多研究團隊投入6G通訊的研究。本論文提出了一個低成本，低複雜度的6G系統架構，利用太赫茲光混頻技術生成太赫茲光，並利用低成本太赫茲包絡接收器進行接收。同時，本論文也調查該系統在6G FLAGSHIP白皮書定義頻段中的表現。為了更進一步降低更新成本，本論文也提出跨世代通訊整合。利用實驗室目前可用資源，整合太赫茲通道以及5G通訊裡面的3.5GHz 通道。太赫茲通道以資料量為6Gbps的為壓縮4K影片為例，3.5GHz通道以1Gbps頻寬的OFDM和16QAM的訊號為例。利用同一條約為15公里的長光纖串連中央機房與基地站，基地佔可利用解多工器自行切換通訊通道。

The generation of communication typically goes to the next generation every ten years. In 2020, 5G communication has already been applied in our daily life. In order to purpose and implement the next generation communication system, 6G. A lot of research groups have already been focusing on the development of 6G communication. The thesis purpose a low-cost, low-complexity 6G communication system. In the system, the terahertz wave is generated with the technology of terahertz photomixing and a low-cost and low-complexity envelop detector is applied to receive the signal. Also, the performance of the system is investigated. In order to further lower down the system cost, we implement a across-generation communication system based on our available resources. The terahertz-link and 3.5GHz-link is integrated. For terahertz-link, a 6Gbps uncompressed 4K video live streaming is demonstrated. For 3.5Ghz-link, an OFDM and 16QAM with 1GHz bandwidth signal is demonstrated. A 15 km long fiber connects the central office and base station. The base station can be switched with a demultiplexer.

摘要 II
ABSTRACT III
ACKNOWLEDGEMENT IV
TABLE OF CONTENTS V
LISTS OF FIGURES VI
LIST OF TABLES XI
CHAPTER 1 INTRODUCTION 1
1.1 GENERATIONS OF WIRELESS COMMUNICATION FROM 1G TO 5G 1
1.2 NEXT COMMUNICATION GENERATION, 6G 3
1.3 RESEARCH MOTIVATION 5
CHAPTER 2 COMPARISON AND DETERMINATION FOR TERAHERTZ COMPONENTS IN OUR 6G COMMUNICATION SYSTEM 7
2.1 TERAHERTZ EMITTERS 7
2.2 TERAHERTZ RECEIVERS 16
CHAPTER 3 WORKING PRINCIPLE AND CONCEPTS IN COMMUNICATION SYSTEM 25
3.1 FIBER-WIRELESS NETWORK 25
3.2 5G GENERATION 29
3.2.1 Orthogonal Frequency Division Multiplexing (OFDM) 29
3.2.2 Square Law Detection 33
3.2.3 Mach-Zehnder Modulator (MZM) 36
3.3 6G GENERTION 40
3.3.1 Terahertz photomixing 40
CHAPTER 4 EXPERIMENT SETUP AND RESULTS DISCUSSION 42
4.1 5G WIRELESS COMMUNICATION SYSTEM (3.5 GHZ LINK) 42
4.2 6G WIRELESS COMMUNICATION SYSTEM 56
CHAPTER 5 CONCLUSION AND FUTURE WORK 78
CHAPTER 6 REFERENCE 80

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