Non-integer-order exponential filters: definitions in the time-domain and frequency-domain

Integer and non-integer-order exponential filters defined in both the time and frequency-domains are investigated in this work. These filters are then approximated utilizing a curve-fitting method leading to a rational integer-order approximating transfer function. The accuracy of the approximation of the exponential filters is confirmed through experimental results obtained using a Field Programmable Analog Array device. A real life application example is also provided, where one of the presented filters is employed for denoising an electrocardiogram signal.