CIC interpolation filter design in the audio decoder

In order to get high-quality audio output in the audio decoder, analog low-pass filter to reduce the design difficulty, then the interpolation filter as its digital signal processing part of an integral important part of CIC filters are commonly used in the interpolation process highly efficient filters, with a simple structure, easy to implement advantages. This article is in the possession before the two half-band filter to provide the basis of four over-sampling, in order to further improve the over-sampling rate designed for multi-stage cascade CIC interpolation filters. First introduced the principle of CIC filter is given CIC filter design methods, and analysis of cascaded CIC filter order of magnitude and the filter selection of the pass-band attenuation and the impact of side lobe suppression, through the MATLAB simulation results validate the design effectiveness and feasibility of the method. For digital audio signal processing provides a feasible method of link.