臺灣博碩士論文加值系統

本篇論文中，我們在FPGA上設計與實現即時單輸入多輸出時變通道模擬器。此通道模擬器的架構在設定系統參數上是彈性的，例如在不同環境下所模擬的延遲擴展、接收入射到達角 正規劃最大都普勒偏移。此通道模擬器的效能被驗證於OFDM訊號在移動環境下，模擬多天線接收與分集訊號處理時的效能差異性。

In this thesis, we design and implement a real-time single-input-multiple output frequency and time selective channel emulator with FPGA. The architecture of the channel emulator is flexible in setting system parameters such as delay-spread profile, angle-of-arrival profile and maximum normalized Doppler shift for emulating various environments. The effectness of this channel emulator is verified by observing the performance variation when emulating multiple antenna reception and diversity signal processing of OFDM signal in mobile environment。

摘要 ..................................................... I
ABSTRACT ................................................ II
誌謝 ................................................... III
目錄 .................................................... IV
圖目錄 ................................................. VII
表目錄 ................................................ XIII
第一章 緒論 ............................................. 1
1.1 研究動機與背景 ...................................................................................... 1
1.2 章節提要 .................................................................................................. 2
第二章 無線移動通道統計特性描述 ......................... 3
2.1 無線移動通道簡介 .................................................................................. 4
2.2 小尺度傳輸模型(Small Scale Propagation Model) ................................ 7
2.2.1 多重路徑傳輸效應(Multipath Propagation Effect) ................................. 8
2.2.2 延遲擴展(Delay Spread)及功率延遲概觀(Power Delay Profile) ........... 9
2.2.3 都普勒效應(Doppler Effect) .................................................................. 10
2.2.4 時散參數(Time Dispersion Parameters) ................................................. 11
2.2.5 都普勒延展(Doppler Spread)與同調時間(Coherent time) ................... 13
2.2.6 小尺度衰落的類型(Types of small scale fading) .................................. 15
2.3 多重路徑衰減通道模型(Small Scale Propagation Model) .................. 17
2.3.1 Rayleigh 衰減分佈 ................................................................................. 18
第三章 SIMO 通道相關性及通道模擬 ............................................... 19
3.1 Jakes 模擬器數學緣由 .......................................................................... 20
3.1.1 Jakes 模組模擬 ...................................................................................... 23
3.1.2 改良式Jakes 模組模擬 ......................................................................... 33
3.2 角度延展與功率方位頻譜(Angle spread and Power Azimuth Spectrum)
…………………………………………………………………………40
3.3 MIMO 技術特性簡介............................................................................ 51
3.3.1 空間分集spatial diversity ...................................................................... 52
3.4 The 3GPP MIMO Channel Model ......................................................... 54
3.4.1 SIMO 時變通道模擬 ............................................................................. 56
第四章 FPGA 實現SIMO 多路徑衰減通道模擬器 ............................... 63
4.1 系統驗證平台介紹 ................................................................................ 63
4.2 線性時變系統模擬器( Linear Time Varying ,LTV system Emulator) 64
4.2.1 時變通道摺積模擬器(Time Varying Convolution Emulator) ............... 65
4.3 多路徑衰減通道產生器(Multipath fading channel Generator) ............ 66
4.3.1 都普勒偏移頻率模組(Doppler Shift frequency module) ...................... 67
4.3.2 座標旋轉演算法(CORDIC Algorithm)及硬體設計 ............................. 68
4.3.3 都普勒位移相位加總與路徑增益相乘 ................................................ 70
4.3.4 線性內差產生器(Interpolator Generator) .............................................. 71
4.4 一對多線性時變系統模擬器( SIMO LTV system Emulator) .............. 72
4.4.1 一對多多路徑衰減通道產生器 ............................................................ 73
4.5 多對多天線衰減通道產生器 ................................................................ 75
4.6 一對二多路徑衰減通道硬體模擬結果 ................................................ 77
第五章 SIMO 時變通道對DVB-T 系統效能的影響 .............................. 85
5.1 DVB-T 歐規數位電視地面廣播系統規格與參數 ............................... 85
5.2 通道估測與等化 (Channel Estimation and Equalization) .................... 90
5.2.1 最小平方法通道估測 (Least Square Channel Estimation) .................. 92
5.2.2 通道響應內插 (Interpolation of Channel Response) ............................ 93
5.3 系統效能分析 ........................................................................................ 94
5.3.1 最大比值合併(Maximal Ratio Combining) .......................................... 95
5.3.2 等增益合併(Equal Gain Combining) ................................................. 96
5.3.3 SIMO 角度均勻分佈及不同速度及不同天線間距模擬 ..................... 97
5.3.4 SIMO 角度集中入射及不同速度及不同天線間距模擬 ................... 101
第六章 結論與未來發展 ................................................................................... 110
參考文獻 ..................................................................................................................... 111

[1]ETSI EN 300 744, Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television, European Standard.
[2]W. C. Jakes. “Microwave Mobile Communications” [M]. IEEE Press, Wiley Interscience, 1994.
[3]T.S.Rappaport, “Wireless Communications-Principles and Practice”,2nd Ed.,Prentice-Hall
[4]Lee,William C.Y., “Mobile Communication Design
[5]Agilent MIMO Channel Modeling and Emulation Test Challenges Applicaiion Note
[6]3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Spatial channel model forMultiple Input Multiple Output (MIMO) simulations。3GPP TR 25.996 V6.1.0 (2003-09)
[7]Compact Rayleigh and Rician fading simulator based on random walk processes. A. Alimohammad S.F. Fard B.F. Cockburn C. Schlegel Published in IET Communications Received on 13th May 2008 Revised on 26th November 2008
[8]SMIMS VeriLink User Guide For VeriEnterprise Xilinx
[9]Siavash M. Alamouti,”A Simple Transmit Diversity Techniaue for wireless Communications”, IEEE JOURNAL SELECT AREAS VOL.16, NO.8, OCT. 1998
[10]顏建安，”適用於OFDM系統下之通道模擬器研究與實現實現”，中央大學碩士論文。
[11]陳盈志，”時空編碼OFDM-CDMA信號之偵測”，成功大學碩士論文。
[12]羅振原，” 行動無線通訊衰減通道模擬器之研究”，雲林科技大學碩士論文。