Implementation of IMDCT for MPEG2/4 AAC on 16-bit fixed-point digital signal processors

MPEG-2/4 AAC coding standard provides coded music with high quality. Since the IMDCT used in the standard for a long window has a length of 2048, it is necessary to use a fast algorithm for lower complexity. When these algorithms are implemented on a fixed-point environment, arithmetic accuracy becomes a problem. This paper discusses this issue and suggests a suitable algorithm to be used for 16-bit fixed-point digital signal processors (DSPs).