在數位通訊傳輸系統當中,重覆式解調結合重覆解碼的演算方法十分適合在使用在非同調區塊衰退通道之下,經由內部解調器解調以及外部解碼器的重複解碼反覆更新訊息的動作,我們可藉由更新接收訊息來獲得更佳的錯誤率。在這篇論文之中,我們討論三種不同的非同調解調器在各種同調區間,相位量化等級的情況下的模擬結果。此外在比較各個解調器的優劣之後,我們結合兩種非同調解調器提出一個新的非同調解調器。 For digital communication transmission system, the joint noncoherent demodulation and decoding scheme is suitable for noncoherent block fading channel. By the action of iterative demodulation and iterative decoding, the information is updated repetitively and thus the error performance becomes better. In this thesis, three noncoherent demodulation schemes are employed for different coherent length and quantization level. We compare various noncoherent demodulators and propose a new noncoherent demodulation algorithm by combining two noncoherent demodulators.