在正交分頻多工 (OFDM) 系統中，載波間干擾 (ICI) 是影響系統效能的重要因素；這是由於載波頻率間隔 (subcarrier spacing) 窄以及允許頻譜重疊，使得載波間的正交特性 (orthogonality) 易受傳送、接收兩端震盪器不匹配及都卜勒 (Doppler) 效應所破壞的緣故。 傳統壓抑載波間干擾技術，大致分為線性相關碼 (correlative code) 壓抑載波間干擾的技術以及置於OFDM解調器前之窗化技術 (Windowing scheme)。 線性相關碼 (correlative code) 壓抑載波間干擾的技術不會降低頻譜效率，但是在壓抑頻譜間干擾的效能上卻不夠顯著，而且可能造成錯誤跨OFDM符號傳遞，而置於OFDM解調器前之窗化技術在壓抑頻譜間干擾的效能上相當顯著，然而其效能會因為窗形函數特性的不同而有相當大的差異。
在此篇研究中，我們首先針對王與黃線性相關碼壓抑載波間干擾技術，我們提出了一個新的壓抑載波間干擾的技術，其中主要的不同在於，我們提出的方法中，結合了原來的王與黃線性相關碼壓抑載波間干擾技術以及置於OFDM解調器前之窗化技術。 和原本的系統相比較，我們所提出之方法能只需額外付出些微的硬體複雜度更有效的壓抑載波間干擾，再者，因為王與黃線性相關碼壓抑載波間干擾技術，可等效為置於OFDM調變器後之窗化技術，因此我們結合原先置於OFDM解調器前的窗形函數和王與黃窗形函數，進而提出一個全新的窗形函數。 針對結合了原來的王與黃線性相關碼壓抑載波間干擾技術以及置於OFDM解調器前之窗化技術，我們提供了載波能量對干擾能量比(CIR)的理論推導以及數個電腦模擬結果，兩者都顯示了新的方法能更有效的壓抑載波間干擾。 再者，為了驗證新的窗形函數壓抑載波間干擾效能，我們提供了載波能量對干擾及雜訊能量比(SINR)的理論推導，也提供了數個電腦模擬結果，在理論及實驗結果都顯示了新的窗形函數能有著更好的壓抑載波間干擾能力。

Orthogonal frequency-division multiplexing (OFDM) digital communication system is very sensitive to frequency errors caused by frequency differences between transmitter and receiver local oscillators.
In this thesis, we propose a new intercarrier interference (ICI) suppression scheme that can be regarded as a combination of the correlative coding scheme and the windowing scheme. As compared to the original correlative coding scheme, the proposed approach achieves better performance for ICI suppression. Simulation results show that the improvement in carrier-to-interference ratio (CIR). Furthermore, a new window, which combines Wang-and-Hung window and the polynomial Nyquist window, is proposed and applied to OFDM systems for reducing frequency offset induced ICI in the receiver. Simulations show that the improvement in signal-to -interference plus noise ratio (SINR).

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