Methods for Avoiding the Checkerboard Distortion Caused by Finite Word Length Error in Multirate System

We propose two methods for avoiding the checkerboard distortion which is caused by finite word length error. The first method is deriving a bit length of filter taps required for avoiding the checkerboard distortion under a certain word length. In the second method, the checkerboard distortion can be avoided by using the cascade structure which consist of zero-hold kernel and a time-invariant filter factorized from a filter with structure for avoiding the checkerboard distortion under linear conditions. It is demonstrated by simulations that we can avoid the checkerboard distortion by using these proposed methods. key words: checkerboard distortion, multirate system, finite word length error, cascade structure