Abstract: In this under-sampling of pass-band signal, the fractional ratio Sampling Rate Conversion(SRC) is a procedure which requires a lot of computations. The low-order linear interpolating will incur more aliase noise. Based on the polyphase filter architecture and minimum-operation principle, this paper integrates the interpolating, filtering, and decimating operations in the course of SRC, and presents three architectures for efficient conversion. It also compares the operation efficiencies of the three architectures, and finally gives the computer simulation results on a typical signal.