Programmable digital filters for optical servo system

This paper introduces the digital filter architecture that reduces power and chip-size. The implementation is largely divided into two methods. One is the software filter based on DSP, the other is the hardware digital filter. The disadvantage is that it's difficult to design a high sampling rate and to change types. In order to solve problems, we propose the new structure of the programmable digital filter, which includes a memory for controls of types and sampling-rates.