使用離散哈特利轉換(Discrete Hartley Transform ; 簡稱 DHT )之濾波器組多載波（Filter Bank Multicarrier ; 簡稱 FBMC）系統，可以用作離散傅里葉變換（Discrete Fourier Transform ; 簡稱 DFT）的替代方案，因為它有可能以更低的複雜度實現更好的性能。然而，可用於基於DFT的FBMC的常規通道估計方法不能直接應用於基於DHT的FBMC，其在任何兩個鏡像對稱子載波（具有位元反轉索引）之間具有一些不同的通道分集。在本論文中，我們提出了一種前置序列設計，用於同時估計基於DHT的FBMC系統中每對奇數（或偶數）鏡像對稱子載波的通道增益。前置序列結構是由四個頻域前置序列向量組成的特定時頻網格，其元素被排列為 1，使得每對鏡像對稱子載波的通道估計的均方誤差最小化。使用估計結果，可以簡單地通過線性內插獲得剩餘子載波的通道增益。仿真結果表明，所提出的前置序列設計為不同的ITU通道模型帶來了良好的通道估計的均方誤差，其中與完美通道信息下獲得的相比其錯誤率性能具有大約2dB的損失。

Filter bank multicarrier (FBMC) transmission using the discrete Hartley transform (DHT) can be used as an alternative to the discrete Fourier transform (DFT) because of its potential to achieve better performance with reduced complexity. However, conventional channel estimation methods available for DFT-based FBMC cannot be directly applied to DHT-based FBMC, which has some distinct channel diversity between any two mirror-symmetrical subcarriers (with bit reversal indexes). In this thesis, we propose a preamble design for simultaneously estimating the channel gains of each pair of odd-numbered (or even-numbered) mirror-symmetrical subcarriers in DHT-based FBMC systems. The preamble structure is a specific time-frequency lattice consisting of four frequency-domain pilot vectors whose elements are arranged to be 1, such that the mean-squared error (MSE) of channel estimation is minimized for each pair of mirror-symmetrical subcarriers. Using the estimated results, the remaining subcarrier’s channel gains can be obtained simply by linear interpolation. Simulation results show that the proposed preamble design leads to good MSE performance of channel estimation for different ITU channel models, where the bit error rate performance has about a 2 dB loss, in contrast to that obtained under perfect channel information.

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