FIR Filter for Feed-Forward Compensation of MEMS Actuator

The paper describes a compensation filter design for the electrostatic MEMS actuator, which is used to move a mirror for beam spot stabilization in a Free-Space Optical receiver. The actuator represents a dynamical system of the second-order with a highly oscillating response. The purpose of the filter is to prevent excitation of MEMS oscillations. The paper describes a simple three-tap FIR filter whose parameters have a direct relation to the actuator model and allow simple in-application tuning during the device operation.