Design of an Optimal IIR Full-Band Digital Differentiator

In this paper a novel metaheuristic algorithm called the Coati optimization algorithm (COA) is used to design a 2 nd order infinite impulse response (IIR) full-band digital differentiator (DD) by optimizing the filter coefficients. The objective is to closely approximate the frequency response of the proposed filter so that it tries to meet the ideal frequency response characteristics of an ideal differentiator. COA is a population-based metaheuristic algorithm which imitates the natural behavior of coatis when they are attacking iguanas and evading from predators. Every member of the coati's population represents a possible optimal solution based on their positions in the search space. The COA based design of the IIR DD is compared with various other designs obtained with traditional algorithms and proved to be better in terms of various error performance parameters. Overall, these improved results for the proposed filter can become an inspiration for various digital signal processing applications.