Exploration of visual teaching for digital filter design

This paper presents a dynamic demonstration system based on pulse and sound signal, which is to be used in the teaching of digital filter design. What we can observe in the system are as follows: the change of filtering performance as pole-zeros changing; the frequency domain characteristics of filter and the effects of amplitude frequency characteristics; phase frequency characteristics effects on filtering performance; the effects of filter's order on the filtering performance. Students can feel the effects of filter by observing the visual teaching system and hearing the filtered sound signal, which can enhance students' interest.