在頻率選擇性通道中使用最小平方法於正交分頻多工通道估測

A Least-Squares Approach for OFDM Channel Estimation in Frequency-Selective Channels

楊國豐(Kuo-Feng Yang)

指導教授 ： 嚴雨田

淡江大學/工學院/電機工程學系碩士班/碩士(2008年)

https://doi.org/10.6846/TKU.2008.00545

摘要

通道估計器通常對於實際通道的長度是未知的，設計時常以通
道的最大可能長度作通道估測。本篇論文針對這種在估計器中，含有
多餘估計參數的情況，討論其對於估計準確度的影響，並依此推導出
最佳估計器的訓練序列之設計準則。估計的方法為最大可能估計，精
確的數學分析公式被提出，並與電腦模擬做比較，驗證出理論與實際
模擬結果吻合。此結果可作為將來進一步在改進通道估計準確度的先
導研究，藉以提出新的通道參數估計器。

關鍵字

正交分頻多工 ； 最大可能估計 ； 頻率選擇通道 ； 最佳訓練序列 ； 通道估計

並列摘要

The practical channel length for a channel estimator is usually unknown. The maximum possible channel length is therefore assumed a priori. In this paper, we explore the effect of channel information redundancy on the channel estimation accuracy in orthogonal frequency division multiplexing (OFDM) systems. The optimum training sequence for channel estimation is discussed. Theoretical analysis and Monte Carlo simulation are compared and show great agreement. Maximum-likelihood (ML) estimation is used for the channel estimation. The study leads to a novel channel estimator design.

並列關鍵字

Orthogonal frequency division multiplexing (OFDM) ； least squares (LS) estimation ； frequency-selective channels ； optimum training sequence ； channel estimation

參考文獻

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[3] J. A. C. Bingham, “Multicarrier modulation for data transmission: An

idea whose time has come,” IEEE Commun. Mag., vol. 28, May 1990, pp. 5–14.

[4] J. A. C. Bingham, “Multicarrier modulation for data transmission: an idea whose time has come”, IEEE Comm. Magazine, vol. 28, Issue 5, May 1990, pp. 5-14.