设计的抽取内插系统，利用多相滤波结构，先3倍抽取，在8倍内插，比较采用多相滤波和不采用多相滤波方法的区别(The designed decimation interpolation system uses a polyphase filtering structure, first 3 times decimation, and interpolation within 8 times, and compares the difference between polyphase filtering and polyphase filtering)