A synthetic aperture radar correlation system including a moving diffuser located at the image plane of a radar processor. The output of the moving diffuser is supplied to a lens whose impulse response is at least as wide as that of the overall processing system. A significant reduction in clutter results.
A method of operating a computing machine for reducing speckle noise in video images, particularly radar images, utilizes a complementary hulling technique on vertical pixel grids of the array. The vertical pixel contours which are subjected to the complementary hulling are derived from intersections of vertical grids with conceptual superposed gray-scale surfaces which have front end values corresponding to the gray-scale pixel values. The invention provides the significant advantages of decaying small image features, such as speckle noise at a significantly faster rate than large image features, such as target returns.