Optical Fourier processor and point-diffraction interferometer for moving-object trajectory estimation.

A hybrid optical-digital signal processing system that estimates the trajectory of moving targets in a two-dimensional field at video frame rates was developed and constructed. The hybrid system is particularly well suited to the trajectory estimation of small, barely discernable, moving objects of unknown position and velocity in high-resolution image sequences. The system uses an optical Fourier processor and a point-diffraction interferometer to calculate the frequency-domain representation of moving objects from which their trajectory is estimated by use of conventional electronic processing techniques. In a series of experiments, target velocities were estimated to within 4% of their actual value and direction was estimated to within 3 deg.