Abstract: Apparatus and methods for enhancing the accuracy of height above ground measurements in which the registration error between successive images taken of the terrain over which an aircraft is flying is minimized, the earlier image having first been transformed according to measurements of the aircraft linear and angular velocities, the focal length and attitude of the image sensor, and an initial, coarse height estimate. By an iterative process, a more accurate height estimate is obtained.

Abstract: Apparatus for the improvement of inertial navigation system (INS) position/velocity comprises frame stores for storing sequential images from a video camera and a comparator for comparing pixels in predicted images, derived from earlier stored images as modified by INS linear and angular velocity outputs, with pixels in actual later stored images, to derive a velocity error correction signal which is used to correct the INS output. The video processing correction system described is passive and hence does not reveal the aircraft's whereabouts as would be the case with other positional correction systems using radar, nor does it rely on systems outside the control of the INS, e.g., GPS, nor is it reliant on a vast terrain feature database.

Abstract: The present invention provides a system and method for improving a user's ability to direct the computer to perform a desired function. A single uniform input control is provided that receives user input, such as from a keyboard. The present embodiment then parses the user input to determine its input type and whether the input type corresponds to a single, recognized action performable by the computer and, if so, performs the action. Such recognized actions include navigating to an Internet site and composing an e-mail message. If the input type does not correspond to a single recognized action, the user input is submitted to at least one text processor, such as a natural language processor, that analyzes the user input to obtain at least one interpretation corresponding to an action performable by the computer. The at least one interpretation is returned to the user who may select a desired action from among the listing of interpretations.

Abstract: Apparatus and methods for enhancing the accuracy of height above ground measurements in which the registration error between successive images taken of the terrain over which an aircraft is flying is minimised, the earlier image having first been transformed according to measurements of the aircraft linear and angular velocities, the focal length and attitude of the image sensing means, and an initial, coarse height estimate. By an iterative process, a more accurate height estimate is obtained.

Abstract: Method and apparatus for isolating optical feedback in a laser interferometer having a laser light source from which a linear polarized outgoing laser beam of certain polarization orientation is derived. The interferometer also redirects the outgoing laser beam to form a return laser beam directed to a receiver. The outgoing laser beam and the return laser beam are physically close and are substantially parallel. The linearly polarized outgoing laser beam is converted to circular polarization. A portion of the circularly polarized return laser beam directed toward the laser light source is converted back to linear polarization with polarization orientation orthogonal to the polarization orientation of the outgoing laser beam. A portion of the circularly polarized return laser beam directed toward the receiver is converted back to linear polarization with polarization orientation being substantially the same as the polarization orientation of the outgoing laser beam.