Serial-parallel connection of direct sampling mixer

In this paper, a novel parallel connection for Direct Sampling Mixer (DSM) and its design method have been proposed. The transfer function of IIR in the conventional DSM can be designed only for the second order that leads to a poor skirt characteristics. To alleviate this problem, a parallel connection of DSM for the higher order of IIR has been proposed. By this structure, higher order of polynomials both in the denominator and numerator can be designed. So, an excellent attenuation characteristic can be achieved by specifying frequencies of attenuation pole.