自從人類進入資訊化時代以來，相關產業發展迅速，人們對於無線通訊的需求不斷增加，使得存在於自然界中的頻譜資源日益珍貴，然而實際去調查發現，雖然大多數的頻段都已被分配用途，頻譜的使用效率卻不高，也因此我們需要一個智慧型的無線通訊系統，配合因半導體產業與DSP的成熟所發展出之軟體定義無線電，進行頻譜感測、頻譜管理和頻譜空間的發展。

本論文首先介紹智慧型無線通訊系統，感知無線電的源由與發展，雖然近年來在時間點上是軟體定義無線電架構先被提出，接著才發展感知無線電，但是實際上早在當初無線電系統被發明出來時，因為情勢的壓迫，不得不運用感知無線電的概念，在序論中也舉了兩個實際例子作為驗證。

在接下來的章節中，主要是針對未來5G將要採用的新概念：LTE-U與LAA，進行探討，主要是基於在4G時代就被提出之載波聚合技術，將免執照頻段中多餘的頻寬借給LTE的使用者，達到提升傳輸速率的效果，因此本論文在第三章利用軟體定義無線電，設計一個雙頻段信號接收系統，不僅能夠兩通道即時接收並監測空氣介質中的信號，還能夠依據收到信號之RSSI大小，藉由演算法估測MCS、計算吞吐量，進而得出頻譜效率，最後也實際使用手機APP測量吞吐量與實驗結果進行比較。

第四章則承接上一個章節之雙頻段信號接收系統，獲得頻譜並分析完成之時，經由主控端進行載波聚合，並且將硬體設備之接收端關閉，切換至傳送端進行傳播，最後再切換回接收端繼續接收信號，為一個自動化系統。

Ever since entering the age of information and communications, the IT industry has grown exponentially. Due to the growing demands for wireless communications, spectrum has become more precious. However, we find that although most of the bands have been allocated, the efficiency of spectrum usage is not optimal. Therefore, we need a smart wireless communication system, for example, Software-Defined Radio (SDR), in which silicon IP and DSP are implemented to enable spectrum sensing, spectrum management, and spectrum space allocation.

First in this thesis we introduce an intelligent wireless system (i.e., SDR), and development of Cognitive Radio (CR). Although in recent years SDR architecture was first proposed, followed by development of CR, in fact, the concepts of CR had been applied when the radio was just invented. In introduction, two examples of CR are cited.

In the next chapter, we focus on introduction of 4G/5G, LTE-U (U for Unlicensed) and LAA (License-Assisted Access). In 4G, Carrier Aggregation (CA) technique has been implemented on licensed bands for the purpose of higher data rates. In 5G, the CA technique will be applied for both licensed and unlicensed bands. In Chapter 3 we implemented a dual-band signal receiver system on a SDR hardware by National Instruments (NI) for the signals. In addition to receiving and monitoring the dual-band signals in air instantly, the system also estimates MCS (Modulation and Coding Scheme) and throughput from RSSI, and spectrum efficiency for the individual bands. Finally, we compare the result with actual throughput test by a phone’s app.

Following the dual-band receiver system developed in previous chapter, we carry out carrier aggregation scheme and transmit the aggregated signal by switching from receiving port to transmitting port in Chapter 4. After the transmission, the SDR resume the CR mode.

論文審定書...........................................................i
致 謝..............................................................ii
中文摘要............................................................iv
英文摘要.............................................................v
圖 次...............................................................x
表 次............................................................xiii
第一章 序論..........................................................1
第二章 感知無線電....................................................3
2.1. 軟體定義無線電發展.........................................3
2.1.1. 軟體定義無線電硬體架構...............................4
2.1.2. 軟體定義無線電軟體架構...............................5
2.2. 感知無線電.................................................6
2.2.1. 頻譜使用現況.........................................6
2.2.2. 感知無線電發展.......................................7
2.3. 頻譜感測..................................................10
2.3.1. 頻譜感測的問題......................................11
2.3.2. 頻譜空洞............................................13
2.3.3. 能量偵測法(Energy Detection) .......................16
2.3.4. 匹配濾波器偵測法(Matched Filter Detection) .........19
2.3.5. 共變異數偵測法(Covariance-Based Detection) .........20
2.4. 頻譜管理.................................................20
2.4.1. 頻譜分析和決定......................................22
2.4.2. 頻譜共享............................................24
2.4.3. 動態存取頻譜.........................................25
2.5. 章節討論..................................................29
第三章 雙頻段信號接收系統...........................................30
3.1. 免執照頻段與LTE ...........................................30
3.2. 軟體無線電系統架構.........................................31
3.3. 頻譜感測...................................................33
3.3.1. 等化器..............................................34
3.3.2. 能量偵測法..........................................35
3.3.3. 頻譜Waterfall ......................................37
3.4. 雙頻段頻譜感測流程.........................................38
3.4.1. 資料分割(Data Split) ................................39
3.5. 頻譜效率(Spectral efficiency) .............................40
3.5.1. 調變與編碼方案估測(MCS estimation) ..................41
3.5.2. 吞吐量計算(Throughput calculation) ..................43
3.5.3. 獲取頻譜效率.........................................48
3.6. 實驗結果...................................................49
3.7. 章節討論...................................................56
第四章 載波聚合.....................................................57
4.1. 載波聚合介紹...............................................57
4.2. 利用軟體定義無線電實行載波聚合.............................60
4.2.1. 載波聚合系統架構.....................................60
4.2.2. 實驗結果.............................................62
4.3. 章節討論...................................................64
第五章 結論與未來工作...............................................65
5.1. 結論.......................................................65
5.2. 未來工作...................................................65
參考文獻............................................................66

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