This a good code for Speech Analysis&Synthesis
File list:
GSM Project
..........\AutoCorrelate.m
..........\decode1.m
..........\encode1.m
..........\GSM.m
..........\lpc.m
..........\MiddleShap.m
..........\myFilter.m
..........\newspeech.wav
..........\pitchcode.m
..........\PitchDetect.m
..........\pitchesdetect.m
..........\speech.wav