Abstract: Three-dimensional surface illumination using curved laser sheets is described for optical flow measurements over conformal curved surfaces. The illumination method is applicable to many different optical-based flow visualization and measurement techniques, particularly for particle image velocimetry. An alignment sheet increases the accuracy of determining the position and movement of particles used in optical-base fluid flow techniques.

Abstract: A satellite navigational receiver landing system having retrofit compatibility with integrated landing system (ILS) receivers, in accordance with the invention, includes radio frequency circuitry which converts satellite signals into intermediate signals. A first processing channel coupled to the radio frequency circuitry generates a first position, velocity and time (PVT) solution as a function of the intermediate signals, and provides a PVT data output. A second processing channel coupled to the radio frequency circuitry generates a second PVT solution as a function of the intermediate signals. Monitor circuitry provides monitor output signals as a function of the first and second PVT solutions. Shutdown circuitry provides the first PVT solution to the PVT data output under the control of a shutdown signal from the monitor circuitry.