As　one　of　the　current　most　potential　low　bit　rates　speech　coding　schemes,　waveform　interpolation　model　with　its　high　performance,　has　been　paid　more　and　more　attention.　Based　on　a　kind　of　Singular　Value　Decomposition　method　for　decomposing　Characteristic　Waveform　in　WI　speech　coding,　the　magnitude　spectrum　of　CW　is　perceptually　divided　into　basic　matrix,　transitional　matrix　and　supplemental　matrix　to　be　quantized　respectively,　which　effectively　reduce　the　computational　complexity;　In　addition,　there　are　three　patterns　to　represent　the　magnitude　spectrum　of　CW　combined　by　the　matrixes　above,　and　then　Periodic　Factor　and　Energy　Entropy　are　introduced　to　indicate　the　periodicity　of　matrix,　which　solved　the　problems　for　quantization　of　parameters　after　SVD　and　improved　the　efficiency　of　coding.　Subjective　A/B　listening　tests　indicated　that　the　reconstructed　speech　quality　of　the　2.4　kbps　SVD-WI　codec　is　a　little　better　than　that　of　2.4　kbps　MELP　coder.