頻譜正交預編碼式正交分頻多工系統的等化器及功率負載器聯合設計

Joint Equalization and Power Loading for Spectrally Orthogonally-Precoded OFDM Systems

蘇偉信(Wei-Hsin Su)

指導教授 ： 鐘嘉德

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00209

摘要

在本篇論文中，我們將頻譜正交預編碼式正交分頻多工系統 (Spectrally Orthogonally-Precoded OFDM，簡稱 SOP-OFDM) 與功率負載技術 (Power Loading，簡稱 PL) 做結合[1]，目的是希望能在有效降低系統位元錯誤率的情況下，同時提供極佳的頻譜效率 (Spectral Efficiency)。在此論文中，我們提出以下兩種架構: 1.同時設計等化器和預編碼器使得 SOP-OFDM 系統的均方誤差 (Mean Square Error，簡稱 MSE) 達到最小 2. SOP-OFDM 系統使用 MMSE 等化器下的預編碼器設計使得高斯近似瞬時位元錯誤率 (Asymptotical Average Instantaneous Bit Error Rate) 達到最小，並驗證出此兩種架構的平均位元錯誤率表現皆優於現有的 SOP-OFDM 系統在使用零強制 ( Zero Forcing ) 等化器下所設計出的功率負載技術[1]。最後，我們會在雙路徑衰減通道下，討論各種正交預編碼在上述兩種架構的平均位元錯誤率表現、均方誤差表現，頻帶外功率特性與複雜度。

關鍵字

頻譜預編碼 ； 正交分頻多工系統 ； 功率負載技術 ； 等化器聯合設計 ； 頻譜效率

並列摘要

In this thesis, we combine Spectrally Orthogonally-Precoded OFDM System (SOP-OFDM) with power loading (PL) techniques in order to improve BER performance and provide very high spectral efficiency [1]. We propose the following two algorithms: 1. Joint equalization and block precoding in order to minimize mean square error of SOP-OFDM system 2. Block precoding design in order to minimize asymptotical average instantaneous bit error rate of SOP-OFDM system with MMSE equalizer. The BER performance of these two systems both outperforms the existing SOP-OFDM systems with power loading design by using Zero Forcing equalizer [1]. Eventually, on two-ray fading channels, we will compare average BER performance, mean square error performance, fractional out-of-band power characteristics and complexity of the spectral codes with different power loading algorithms.

並列關鍵字

Spectral precoding ； orthogonal frequency division multiplexing ； (OFDM) ； power loading ； spectral efficiency

參考文獻

1.劉星宏,2008,《用於頻譜域編碼式正交分頻多工系統功率負載技術》,國立台灣大學電機資訊學院電信工程學研究所碩士論文。

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