POINTING ERROR CORRECTION FOR MEMS LASER COMMUNICATION SYSTEMS

We propose the use of free-space optical communication for information transmission between small airplanes <1m wing span. The transmitter directs a focused laser beam (~ 1mrad full-width-half-max, FWHM) to the receiver using a 2 degree-of-freedom (DOF) MEMS mirror for pointing. Gyroscopes are used to monitor and compensate for short-term motion of the transmitter. Periodic dithering corrects gyroscope drift and tracks the motion of the receiver. A 1 DOF prototype with commercially available mirrors and gyroscopes shows that the proposed algorithms use less than 4 percent of the available communication bandwidth.