Abstract: A functionally and structurally modular, parallelogram-shaped spacecraft. The spacecraft includes a plurality of modules joined to one another along an axis of the spacecraft, wherein each module is devoted to a particular function of the spacecraft, and wherein all of the modules have the same cross-sectional size and geometry. The geometry is approximately a parallelogram in a plane normal to the axis of the spacecraft. The functions include power, processing, propulsion, and the like.

Abstract: A multimedia communication system having a plurality of mobile, fixed location, and portable terrestrial communication terminals. The system links terrestrial communication terminals together through a network of non-geostationary satellites. The satellites communicate with a communication protocol similar to terrestrial communication protocols to reduce protocol conversion. The source and destination addressing uses static terrestrial cells for the uplink and the downlink. The terminal data stream is segmented into communication packets at the terrestrial gateway based on the uplink satellite's determination of system parameters. A control satellite dynamically balances up-links and down-links in the terrestrial areas with over-lapping satellite coverage.

Abstract: A method and apparatus enhance visible contrast within an acquired image for display. The contrast enhancement utilizes all N bands of an original N-band spectral image to produce an M-dimensional enhanced image for display. The method creates an enhanced image from an original image in which the visible contrast in the original image is improved. The original image includes pixels, each pixel having N spectral intensities. The display or printer device which must display the relevant information may be limited to a number of bands M which is smaller than N. Maximum contrast of objects is obtained by emphasizing differences in the N-dimensional pixels by as large differences as possible within the dynamic range of the M-band display space. When M=N=3, this means moving pixels in the display space to utilize the full color palette available on a color monitor or printer. When N>M, a mapping from N space to M space must also be accomplished.

Abstract: A method and apparatus measure the accuracy of and optically calibrate a scan mirror. Both the method and apparatus may operate over a wide range of environmental conditions. The environmental conditions may include variations in pressure from a vacuum to several atmospheres. Similarly, large variations in temperature may be accommodated. The apparatus includes a laser source, a plurality of facet mirrors and a detector. The laser source projects a beam onto a reflective surface of a rotatable scan mirror, which directs the beam to each of the plurality of facet mirrors. Each facet mirror is positioned at a known angle. Each facet mirror in turn reflects the beam from the reflective surface of the scan mirror substantially back onto itself (autocollimation). The angle detector then receives the reflected beam and measures a value related to a return angle of the beam.

Abstract: A reflector for an antenna includes a plurality of reflector elements, each having a transmission line and an aperture at a distal end of the transmission line. Each transmission line having a length which varies in accordance with the position of each aperture relative to the antenna. The varying length of transmission creates a time delay that phases re-radiated waves.

Abstract: A communications system allocates communication bandwidth to calls in such a manner for optimizing network system performance. The system uses knowledge about the state of the past and present network demand, and network resources. Predictions of future demand and future network resources are used to calculate future network performance. Allocation decisions are chosen based on network performance calculations and probabilities of achieving future network states.

Abstract: A method exploits the spectral signature of cloud bases in microwave moisture sounder data to determine cloud base heights. This signature requires the accurate specification of cloud top height, which in a preferred embodiment, comes from the analysis of data provided by an electro-optical sensor (EO) such as the Advanced Very High Resolution Radiometer (AVHRR) instrument flown on operational NOAA satellites. The method includes a receiving step in which satellite EO (visible through infrared) and microwave radiance data of a view of the earth's atmosphere is received. The view has both location and time information. In a determining step, cloud top height is determined based on the EO and infrared radiance data. Moisture profiles of the view are retrieved in a retrieving step based on the microwave radiance data. Subsequently, in a determining step, cloud base heights of clouds in the view are determined using cloud top heights as a constraint in the retrieval of moisture profiles with tile microwave data.

Abstract: The present invention provides a switching power supply which operates at a high efficiency over a wide operating load range. When the output power is below a first power level, the first power converter stage operates in a hard-switching mode and the second power converter stage is off. When the output power is greater than the first power level and less than a second power level, the first power converter stage operates in a soft-switching mode and the second power converter stage is off. When an output power is greater than the second power level, the first power converter stage operates in a soft-switching mode and the second power converter stage operates in a soft-switching mode.

Abstract: A communications system allocates communication bandwidth to calls in such a manner for optimizing network system performance. The system uses knowledge about the state of the past and present network demand, and network resources. Predictions of future demand and future network resources are used to calculate future network performance. Allocation decisions are chosen based on network performance calculations and probabilities of achieving future network states.

Abstract: Stabilization of pointing and stabilization mirror systems is provided by using the inherent moment of inertia of the mirrors. Inertially stabilized mirror systems have mirror orientations and rotation axes such that the mirrors reflect incident radiation parallel to the rotation axes. One mirror is provided for each axis of stabilization. In order to maintain stabilization in space for incident radiation to the mirror, any prior mirrors are provided with rotation axes parallel to the stabilization axis.

Abstract: A flat panel display incorporates an array of color separation microlenses. Each color separation microlens in the array is a single, micro-optical element which disperses color by orders to distinct color spots and focuses these color spots to related liquid crystal sub-pixels located in a common plane. Substantially all of the areas of the color spots fall directly and only on the liquid crystal sub-pixels. Little, if any, light energy is lost by falling outside areas occupied by the individual liquid crystal sub-pixels. Because the color separation microlenses provide the color separation, no color filter is required in the flat panel display. Eliminating the color filters eliminates light losses which are incurred when transmitting light through a color filter. The flat panel display makes more efficient use of light transmitted through the components of the display than was possible with prior art flat panel displays.