對於同調解碼,區塊編碼調變(BCM),是一種有頻寬效益的編碼技術,而最近出現一個新的用於非同調解碼之區塊編碼調變,叫非同調區塊編碼調變(NBC-MPSK),它提供了彈性方便的非同調區塊碼設計方法。然而對於此架構所設計出來的某些碼,用維特比法則解碼太複雜了,因為柵狀解碼時需要太多狀態(states)。 A*解碼法目前已經被使用在線性區塊碼的最大相似解碼上,它可以減少搜索路徑,非常適合用來解區塊碼,在本篇論文中,我們將探討將A*解碼法用在非同調區塊編碼調變上,電腦模擬結果展現了令人滿意的效能。 For coherent detection, block coded modulation is a bandwidth efficient technique. Recently, a novel block coded modulation scheme for noncoherent detection, called noncoherent block coded MPSK (NBC-MPSK) is proposed. The NBC-MPSK provides flexible schemes in designing noncoherent block codes. However, for some codes of NBC-MPSK, the Viterbi decoding is too complicated because the decoding trellis need too many states . A* algorithm has been used to implement maximum-likelihood soft-decoding of linear block codes. It can minimize the search edges. In this thesis, we use A* algorithm for the decoding of NBC-MPSK. Simulation results show that this decoding algorithm has satisfactory error performance.