N-path digital filters

According to the sampling theorem, a faster sampling rate is required in order to process signals containing high frequency components. The processing rate is restricted by the highest operating speed of devices available. This paper presents the design of N-path parallel processing technique which would overcome the speed limitation of present devices. The transfer function of N-path digital filter is shown to be H(z^N), where H(z) is the transfer function of each component filter block. This implies that the overall magnitude response of N-path digital filter is a frequency scaled version of that of component filter. In the proposed paper, a scheme to cancel out the unwanted passbands by cascading several N-path filters is first discussed. Then the design procedure of N-path filter from given specification is illustrated using simple example.