System of Standard Approximations for Optimum Frequency Filter Design
Karel Hájek · 2018
In many practical cases, the designers have to solve the approximation tasks for the design and implementation of the frequency filters, usually choosing the standard approximation type. This concerns the design of both analogue filters and digital IIR filters. Unfortunately, in common practice, the type of approximation is not optimally chosen in many cases. Usually, designers choose a well-known standard approximation, such as Butterworth, without a deeper and more consistent assessment of the essential properties. The resulting implementation of the frequency filter, of course, may not have optimal properties. The presented article offers a rather comprehensive system of standard approximations, from which it is possible to select the optimal solution for this task on the basis of some practical criteria and shows these procedures.