We made an improvement in overcoming the defects in speech signal adaptive delta modulation ( abbr . adm ) , such as slope overloading and grain noise . in this method , numerical sliding average filtering was used for filtering decoding speech signal . experiments and analyses indicate that the method makes waveforms in good agreement between the decoding of adm and the original pulse coding modulation ( abbr . pcm ) signal , and considerably improves , the playback speech quality in naturalness , legibility and under standability 針對語音信號自適應增量調(diào)制( adm )方式中斜率過載和顆粒噪聲缺點,提出了一種改進方法,它利用滑動平均方法對解碼后的信號進行數(shù)字濾波.試驗和分析表明,該方法使解碼后的信號波形與原脈沖編碼調(diào)制( pcm )波形具有很好的一致性,使再生語音質(zhì)量在自然度、清晰度和可懂度方面比改進前均有較大提高