Digital Down Converter Based on Walsh Transform for Digital Receiver

摘要

A multiplication-free digital down converter (DDC) based on the Walsh transform for intermediate frequency (IF) digital receiver is presented. The novel structure mainly consists of a fast Walsh transform (FWT)and an inverse fast Walsh transform (IFWT), both of which can be implemented only by addition and subtraction .Since the transform kernel of the FWT and the IFWT are the same,the implementation complexity of the proposed DDC is significantly reduced. Performances illustrative are compared with those of other DDCs, which include convolution operation. Experimental results show that the proposed method outperforms others and is more suited for real time signal processing of software digital down conversion in digital signal processor (DSP).