A METHOD OF SAMPLE RATE CONVERSION FOR DIGITALLY SAMPLED DATA
Original Publication Date: 1995-Jul-01
Included in the Prior Art Database: 2002-Mar-27
A method of sample rate conversion is presented which has two primary beneJts over previous methods. Thefirst advantage is the minimization of on-line data storage needed by the often large coefficient matrix required by the interpolation filter By evaluating a trun- cated Taylor series expansion of the matrix elements, each filter coefficient is calculated in real-time, as it is needed, eliminating the need to store the coefficient matrix in memory. The second benefit of this method is that the matrix elements can be reevaluated in real- time based on new short term values of sample rate frequency in order to re-align the input and output data streams due to asynchronous sample clocks. The primary drawback of this method is the increase in instruction cycles (MIPS) required to perform the coef- ficient calculations. This method is well suited to the implementation of a single DSP chip solution without the need of external memory.