本篇論文探討以Kalman Filtering演算法處理通訊系統中存在的載波相位同步問題。針對此問題，實務上的解決方法是在接收機端使用一載波同步系統來達成發射與接收端間載波相位的同步，傳統上使用一基於回授控制系統的鎖相迴路來實現載波同步系統，然而因其使用的迴路頻寬為固定，以致在載波回復系統的設計上常是必須在系統的收斂時間與穩態誤差間做一妥協，這對設計者而言亦是一挑戰。有別於傳統上使用鎖相迴路架構的載波同步作法，Kalman Filtering演算法可作為可適性載波同步系統的應用，採用此種架構的主要優點為使用一具可適性調整的迴路頻寬在系統的收斂時間與穩態誤差間取得較佳的妥協，另外透過將載波同步問題導入為一Kalman Filtering的演算法應用，載波同步系統的設計更可簡化為僅設定對系統模型與量測結果的預估誤差程度即可，而有別於傳統上採用的鎖相迴路在設計上需設定迴路中的各個參數值。 In this thesis, we study the adaptive carrier synchronization by using the Kalman filtering technique. Practically, such problem can be resolved by a carrier synchronization loop in the receiver. Conventionally, a feedback loop called the phase-locked loop (PLL) is used to implement the carrier synchronization loop. However, due to the fixed loop bandwidth, the design of a PLL always needs the acquisition time and steady-state phase tracking variation of the carrier recovery loop to be compromised and thus possesses a design challenge for designers.Instead a legacy approach based on the PLL structure, an alternative method is to use the Kalman filtering technique. The major advantage of the Kalman-based scheme over the conventional PLL one is the self-adaptation of loop bandwidth for better compromising the trade-off between fast acquisition and small steady-state phase tracking variation. Moreover, by modeling the carrier drift as a Kalman filtering problem, the design of carrier recovery loops can be further simplified to set the noise condition according to the underlying process model and observations rather than to specify each filter parameter as the conventional PLL requires.
