In the work process of repeating type jammer, the transmitted signal always enters into the jammer's receiver and make it work abnormally. An adaptive interference cancellation structure based on LMS algorithm is suggested to solve this problem. However considering the wideband interference signal, we improved the structure. The focus of this essay is to utilize variable fractional delay filter to make the reference signal and interference signal aligned, thus to improve the effect of wideband signal cancellation. In addition, the structure of the variable fractional delay filter is given. Finally, the effectiveness of the adaptive cancellation in wideband interference signal by using this structure is proved through simulation.