Usingthematrixapproach,weanalyzedtherelationbetweenthelocationofthetransmissioninstopbandandthephaseshift,anddiscussedtheproblemofvaryingthebandwidthofthetransmissionwindow.Thesetheoreticaltesultsinthispaperhaveimportantsignificanceforactualapplicationofthephase-shiftedfibergrating.