通訊通道因時變雜訊的影響，導致訊號傳輸在通訊通道之訊雜比 (SNR)亦不斷在變動，而有效的通道容量會隨著訊號雜訊比變動而改 變。本論文主要在探討通道容量變化時，選擇適當的訊源編碼和通道 編碼並且將其做結合，因兩者編碼速率搭配變化，可使結合產生多種 的影像整體傳輸速率組合以適合傳輸狀態，使其系統效能達到最佳。 本論文藉由四分樹影像分割後進行小波轉換並搭配向量量化完 成訊源編碼，而通道編碼則採用渦輪碼，然後將兩種編碼結合。在通 道容量不同時，進行系統模擬的結果比較，分析整體系統效能的最佳 狀態。 Since the noise varies with the time variable and affects the communication channel, the signal-to-noise ratio of channel constantly varies while the signal transmits. Consequently, the available channel capacity will change while signal-to-noise ratio varies. The objective of this thesis is to investigate the appropriate combination of source coding and channel coding while the channel capacity changes. Since both code rates are different, there is a variety of image system transmission rate. With so many combinations, the key point is to research how to achieve the best system performance. Images are first processed by the Quadtree Segmentation. To acquire the source code, the result is processed by the Wavelet Transform and Vector Quantization. Within channel code, the turbo code is selected.Finally, the source code and channel code are combined. With the various channel capacity combinations, the simulated results are compared and analyzed for the best system performance conditions.