A novel design method for dual-passband IIR digital filters

With the rapid development of wireless communication technology, digital filters are now key components in many modern digital systems. Dual-passband digital filter is an important module of digital filter and has attracted wide attention. This paper proposes a novel evolutionary method to design diversified structure digital filters. Our proposed method using an adaptive multiple-elites- guide composite differential evolution algorithm, coupled with a shift mechanism (AMECoDEs) doesn’t need to use known circuit structures. Structures and parameters are evolved by crossover, mutation, and selection. Thus, our proposed method can directly design the diversified dual-passband digital filter structure and can effectively balance exploration and exploitation to prevent individuals from premature convergence. In our experiment, the connection probability, the subsystem number of the filter structure, as well as the scale factor and the crossover rate of AMECoDEs are explored to determine the optimal configuration. Compared with exiting state-of-the-art evolutionary algorithms for the design of the symmetrical and asymmetrical dual-bandpass filters, our proposed method has the smallest average passband ripple and stopband attenuation with the fastest convergence.