Simple circuit for implementation of an analog stack filter

A simple design for implementing an analog stack filter is presented. The implementation of this design is very simple and economical as it needs only operational amplifiers, resistors and capacitors. The design, starting from the simple case of median filter, is extended to that of larger-point analog median filter, then to that of weighted analog median filter. Similarly, this design is then developed into an analog weighted order statistic filter, and then extended to that of an analog stack filter. The same structure was used for all of these extension, with very small modification and with few additional components. The experimental results for these different circuits, for different cases of inputs are included and these results demonstrate that the designs have performed as they were expected