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.