Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for training and using machine learning models to detect problems in a satellite communication system. In some implementations, one or more feature vectors that respectively correspond to different times are obtained. The feature vector(s) are provided as input to one or more machine learning models trained to receive at least one feature vector that includes feature values representing properties of the satellite communication system and output an indication of potential causes of a condition of the satellite communication system based on the properties of the satellite communication system. A particular cause that is indicated as being a most likely cause of the condition of the satellite communication system is determined based on one or more machine learning model outputs received from each of the one or more machine learning models.

Abstract: The present disclosure provides a satellite control method and apparatus, comprising: receiving a to-be-photographed target site input by a user; calculating first moment information corresponding to each satellite entering the target site, according to location information of the target site and operation orbit information of the each satellite in a plurality of satellites; and determining, from the plurality of satellites, at least one to-execute satellite to photograph the target site according to the first moment information corresponding to the each satellite entering the target site.

Abstract: The present invention discloses a modular deployable antenna mechanism based on a symmetrically structural tetrahedron combination unit. The deployable antenna mechanism is formed by multiple deployable antenna modules, two adjacent deployable antenna modules are connected through a first face plate at the bottom of one deployable antenna module and a second face plate at the bottom of the other deployable antenna module, the first face plate and the second face plate are connected through a Hooke joint, an unconnected first face plate and second face plate of the two adjacent deployable antenna modules are connected through a first synchronizing bar, a middle portion of a bar body of the first synchronizing bar can be folded, and the first synchronizing bar is rotationally connected with the first face plate and the second face plate.

Abstract: A method and system for operating a vehicle having a trip information determination device that continuously determines a current position of the vehicle as current trip information, a transceiver that transmits the current trip information and vehicle information to an evaluation station, a driving strategy determination device that captures whether a bend is in front of the vehicle in the direction of travel, and, if a bend is captured the driving strategy determination device, an optimum driving strategy, in terms of energy consumption for driving through the bend. The determined driving strategy is transmitted from the evaluation station to the and therefore to the vehicle.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for training and using machine learning models to detect problems in a satellite communication system. In some implementations, one or more feature vectors that respectively correspond to different times are obtained. The feature vector(s) are provided as input to one or more machine learning models trained to receive at least one feature vector that includes feature values representing properties of the satellite communication system and output an indication of potential causes of a condition of the satellite communication system based on the properties of the satellite communication system. A particular cause that is indicated as being a most likely cause of the condition of the satellite communication system is determined based on one or more machine learning model outputs received from each of the one or more machine learning models.

Abstract: Method for collaborative observation between a local targeting device and a distant targeting device located at different geographical positions and able to acquire images. The method including: when it is implemented by the local targeting device, execution of a procedure for determining a position of an observed object, referred to as the local targeted object, including application of a method for matching points of interest, determined on a local image by the local targeting device, representing a distant image obtained from the distant targeting device. If matching is successful, the local targeting device determines the position of the local targeted object according to information representing a position of a distant targeted object supplied by the distant targeting device and a transformation law allowing to pair the distant and local points of interest obtained when said matching method is applied and controls display of an image comprising the local targeted object.

Abstract: Provided is a calibration device for an optical device including a two-dimensional image conversion element having a plurality of pixels and including an optical system that forms an image-forming relationship between the image conversion element and a three-dimensional world coordinate space, the calibration device including: a computer, wherein the computer is configured to: obtain calibration data representing the correspondence between two-dimensional pixel coordinates of the image conversion element and three-dimensional world coordinates of the world coordinate space; and fit a camera model representing the direction of a principal ray in the world coordinate space, corresponding to the pixel coordinates, as a function of the pixel coordinates, to the calibration data obtained, thereby calculating parameters of the camera model.

Abstract: Determining an altitude error value associated with an estimated altitude of a mobile device. In certain disclosed systems and methods for determining an altitude error value associated with an estimated altitude of a mobile device, a first error value related to systematic error and a second error value related to statistical error are determined, and the altitude error value is determined using the first error value and the second error value.

Abstract: Methods and apparatuses for communication between a mobile device and a target device are disclosed. Information of a target device is determined by means of at least one element of a mobile device for providing an optical link with the target device. An optical component of the mobile device is then aligned with an optical component of the target device based on said information determined by the mobile device. The target device can obtain information of relative positioning of the target device and the mobile device determined for the purposes of providing an optical link between the target device and the mobile device and the optical component thereof can be aligned with the optical component of the mobile device based on the information.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for training and using machine learning models to detect problems in a satellite communication system. In some implementations, one or more feature vectors that respectively correspond to different times are obtained. The feature vector(s) are provided as input to one or more machine learning models trained to receive at least one feature vector that includes feature values representing properties of the satellite communication system and output an indication of potential causes of a condition of the satellite communication system based on the properties of the satellite communication system. A particular cause that is indicated as being a most likely cause of the condition of the satellite communication system is determined based on one or more machine learning model outputs received from each of the one or more machine learning models.

Abstract: A calibration device for an optical device including a two-dimensional image conversion element having a plurality of pixels and an optical system that forms an image-formation relationship between the image conversion element and the three-dimensional world coordinate space. The calibration device includes: a calibration-data acquisition unit that acquires calibration data representing the correspondence between two-dimensional pixel coordinates in the image conversion element and three-dimensional world coordinates in the world coordinate space; and a parameter calculating unit that calculates parameters of a camera model by applying, to the calibration data acquired by the calibration-data acquisition unit, a camera model in which two coordinate values of the three-dimensional world coordinates are expressed as functions of the other one coordinate value of the world coordinates and the two coordinate values of the two-dimensional pixel coordinates.

Abstract: The antenna device includes an antenna unit (110) mounted so that its direction is adjustable, a motor-driven unit (124, 125) that changes a direction of the antenna unit (110), a camera (130) fixed so that its direction relative to the antenna unit (110) does not change, and a direction adjustment control unit (200) that supplies a drive signal to the motor-driven unit (124, 125) and adjusts the direction of the antenna unit (110). The direction adjustment control unit (200) performs feedback control to return the direction of the antenna unit (110) back to an initial direction based on an image taken by the camera (130). It is thereby possible to maintain the communication quality even when a mechanical vibration occurs in a structure on which an antenna device is mounted.

Abstract: Methods, systems, and devices are described for orienting a satellite antenna. In the methods, systems, and devices of the present disclosure, a satellite may provide multiple spot beams, each of the spot beams associated with a specific coverage area. The satellite may also transmit a wide beam downlink signal over a wide area beam having a coverage area that includes each of the spot beams. The satellite may receive an uplink beacon signal. The satellite antenna may be positioned according to azimuth and elevation determined from ground measurements of the spot beams and the satellite measurements of the uplink beacon signal.

Abstract: Disclosed herein is a tracking system configured to track a product and/or an activity. The tracking system comprises a tracing device and a verification server. The tracing device is coupled with the verification server by means of communication means configured to allow exchange of data between the tracing device and the verification server. The tracing device is coupled with a first satellite localization receiver which is configured to receive signals from a satellite localization system, process the received signals to obtain satellite localization observables, and compute locations based on the satellite localization observables. The tracing device is configured to acquire from the first satellite localization receiver positioning data. The tracing device is further configured to provide the verification server with the positioning data and the satellite localization observable acquired from the satellite localization receiver.

Abstract: Methods, systems, and devices are described for orienting a satellite antenna. In the methods, systems, and devices of the present disclosure, a satellite may provide multiple spot beams, each of the spot beams associated with a specific coverage area. The satellite may also transmit a wide beam downlink signal over a wide area beam having a coverage area that includes each of the spot beams. The satellite may receive an uplink beacon signal. The satellite antenna may be positioned according to azimuth and elevation determined from ground measurements of the spot beams and the satellite measurements of the uplink beacon signal.

Abstract: A sensing system includes integrated sensor locating capability. Sensors can transmit spread spectrum encoded data pulses which are received at mobile nodes. Based on time of arrival information and known locations of the mobile nodes, locations of the sensors can be determined.

Abstract: According to one embodiment of the disclosure, a method for use in telemetry processing includes receiving telemetry data originating from a satellite, such that the telemetry data comprises a plurality of data segments. The method includes processing the plurality of data segments simultaneously and transmitting a signal to the satellite, in response to the processing, for effecting a change in the direction of the satellite.

Abstract: An exoatmospheric device comprises an inertial measurement unit comprising a spin axis gyroscope adapted to obtain data regarding angular rotation of the exoatmospheric device about a spin axis, and at least one off-spin axis gyroscope adapted to obtain data regarding angular oscillation of the spin axis. The exoatmospheric device further comprises a processing unit coupled to the inertial measurement unit and adapted to detect attitude error by analyzing correlations between the measured rotation about the spin axis and the measured angular oscillation of the spin axis.

Abstract: Present novel and non-trivial system, device, and method for generating altitude data and/or height data are disclosed. A processor receives navigation data from an external source such as a global positioning system (“GPS”); receives navigation data from multiple internal sources; receives object data representative of terrain or surface feature elevation; determines an instant measurement of aircraft altitude as a function of these inputs; and generates aircraft altitude data responsive to such determination. In an additional embodiment, the processor receives reference point data representative of the elevation of the stationary reference point (e.g., a landing threshold point); determines an instant measurement of aircraft height as a function of this input and the instant measurement of aircraft altitude; and generates aircraft height data responsive to such determination.

Abstract: A communication system for supporting communications with a target market area. The system includes one or more solar-powered aircraft maintained in, or successively passing through, flight stations or flight patterns around the market area. Each of the aircraft targets limited beamwidth communication antennas on a substantial portion of the target market area. The control system is configured to fly selective flight patterns depending on the aircraft characteristics and the flight conditions. The flight patterns may emphasize high-power-generation patterns such as flying away from the sun for aircraft with wing-mounted solar cells.

Abstract: A method of providing attitude and antenna steering for a spacecraft having a number of reaction wheels and a number of antennas is disclosed. The method includes determining a beta angle, the beta angle being the angle between a sun vector and an orbit plane of the spacecraft, and engaging either a first mode or a second mode in an alternate manner to provide attitude and antenna steering based on the beta angle. A target frame generator for generating information usable to provide attitude and antenna steering for a spacecraft is also disclosed.

Abstract: Methods for mapping and resampling images such as satellite or aerial images are presented, including methods to measure relative displacements of images, methods to refine look directions of an aircraft or satellite for aerial or satellite imaging and methods to ortho-rectify and co-register raw satellite or aerial images.

Abstract: The present invention relates to image satellite planning, and more particularly to a method for allowing a deeper search for high value targets in a time-limited planning environment. In an exemplary embodiment, a method of computing an ordered subset of targets includes using an approximation for the time needed for the satellite to re-orient to a new target, rather than calculating each maneuver time between targets. By approximating the maneuver time rather than calculating it, the calculation time is reduced. Each iteration through the traveling salesman problem takes less time, and more iterations can be accomplished between imaging windows. The iterative process can search deeper into the traveling salesman problem to find a better solution.

Abstract: A method for calculating a trajectory of a satellite following a maneuver includes determining a first estimated trajectory of a satellite using a first sequential mode of operation; performing a thruster burn as a correction maneuver for the satellite; and providing a real-time assessment of the correction maneuver by utilizing a second sequential mode of operation. The second sequential mode of operation includes receiving a data point from an uplink/downlink facility, determining a second estimated trajectory and an estimated thruster performance of the satellite based upon the received data point, and determining a trajectory error of the satellite based upon the received data point. The method further includes repeating the second sequential mode of operation if the trajectory error is above a specified threshold level, and repeating the first sequential mode of operation if the trajectory error is below the specified threshold level.

Abstract: A method for configuring and operating a spacecraft in an orbit that is inclined with respect to Earth's equatorial plane, the spacecraft including at least a solar array, a receive antenna, a transmit antenna, and radiator panels. The method includes the step of nominally orienting the yaw axis of the spacecraft, the roll axis of the spacecraft, and the radiator panels substantially parallel to Earth's equatorial plane, the pitch axis of the spacecraft and rotation axis of the solar array substantially parallel to Earth's polar axis, the Nadir vector in the yaw-pitch plane of the spacecraft, and the transmit antenna and receive antenna to angle ?nom. The method also includes the step of correcting the attitude of the receive antenna and the transmit antenna to maintain a desired degree of the receive antenna and the transmit antenna steered toward a coverage region on Earth's surface.

Abstract: A communication system for supporting communications with a target market area. The system includes one or more solar-powered aircraft maintained in, or successively passing through, flight stations or flight patterns around the market area. Each of the aircraft targets limited beamwidth communication antennas on a substantial portion of the target market area. The control system is configured to fly selective flight patterns depending on the aircraft characteristics and the flight conditions. The flight patterns may emphasize high-power-generation patterns such as flying away from the sun for aircraft with wing-mounted solar cells.

Abstract: Disclosed is a command planning apparatus of a low-earth orbit satellite, and a low-earth orbit satellite control system including the same. The present invention automates the process of executing the command plan for converting the satellite task schedule planned on the ground into telecommands available by the satellite in the low-earth orbit satellite control system, and automatically selects a data set established by the parameters related to the execution task of the satellite according to the mapping rule.

Abstract: Provided are an apparatus and method for executing a telecommand on a geostationary satellite, and an apparatus and method for verifying a telecommand execution status on a geostationary satellite ground control system. When a telecommand on a satellite is executed, the satellite generates command execution verification words for the executed telecommand and adds the generated command execution verification words to a telemetry transfer frame, and thus a satellite ground control system can easily verify the telecommand execution.

Abstract: According to one embodiment of the invention, a stationkeeping method for a geostationary satellite includes determining a gravitational force of the sun on the satellite at a beginning of a stationkeeping operation and a gravitational force of the moon on the satellite at the beginning of the stationkeeping operation. An initial inclination vector of the satellite is determined at the beginning of the stationkeeping operation that accounts for a first set of one or more perturbations affecting the orbit of the satellite. A maneuver strategy is determined to correct for a second set of one or more perturbations affecting the orbit of the satellite without accounting for the first set of one or more perturbations affecting the orbit of the satellite. Finally, a maneuver is performed on the satellite according to the maneuver strategy.

Abstract: A satellite system provides geosynchronous satellites in elliptical orbits in respective elliptical orbital planes separated by 120 degrees. The satellites traverse a common figure-eight ground track comprising northern and southern loops. The satellites are controllably switched to operate the satellite currently traversing the northern loop to deliver a selected signal (e.g., a selected frequency signal) to satellite receivers.

Abstract: A system for providing attitude and antenna steering for a spacecraft is disclosed. The spacecraft has a number of reaction wheels and a number of antennas. The system includes control logic configured to: determine a beta angle, the beta angle being the angle between a sun vector and an orbit plane of the spacecraft, and alternately engage either a first mode or a second mode to provide attitude and antenna steering based on the beta angle.

Abstract: A system is provided that includes an optical arrangement, an assembly of a plurality of detectors, and a signal processor. The optical arrangement is capable of viewing a scene that includes an object, where the scene is capable of moving through a field of view of the optical arrangement during each of a plurality of transit periods. The detectors of the assembly are arranged in a vertical scanning direction corresponding to a direction of movement of the scene, and are separately capable of producing an image of the object for each transit period in accordance with a time-delay integration technique. The signal processor, then, is capable of determining the angular position of the object for each transit period based upon the images produced by the detectors.

Abstract: A positioning system for a geostationary satellite according to the present invention comprises a plurality of outer orbit satellites revolving around the earth in equatorial orbit and polar orbit having higher altitude than that of the geostationary satellite; and at least one control station performing orbit determination using tracking data for the outer orbit satellites, and then transmitting consequent orbit data to the outer orbit satellites. The outer orbit satellites transmit to the geostationary satellite their own navigation data, clock data and correction data generated using the orbit data received from the control station. The geostationary satellite calculates its own position using the navigation data, the clock data and the correction data, and performs position control and attitude control autonomously with onboard sensors and actuators.

Abstract: This disclosure provides a communications system using a span-loaded flying wing, traveling at relatively slow speeds, that can remain airborne for long periods of time. The communications system uses the airplane as a long term high altitude platform that can serve at lest one of a number of potential functions. One function is to link to a ground station using radio wave signals and a satellite using optical signals. Another function is to serve as a relay station between ground communication nodes and individual end-users. Because the aircraft can tightly hold a station, the end-user's antennas do not need to be continuously adjustable. For such a system, a large number of aircraft can be used, with the end-user antennas being configured for a narrow beamwidth so as to allow frequency reuse for different communication links.

Abstract: Methods and structures are provided for reducing pointing errors ? of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes ? and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location ? and which measures received signal strengths ?. Pointing errors ? of the transmit beams are then determined from the estimated pointing attitudes ?, the terminal location ? and the signal strengths ? and the pointing errors ? are subsequently reduced by revising the pointing attitudes ?. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

Abstract: An inertial reference system for a spacecraft includes an attitude control assembly and a plurality of force sensors. The attitude control assembly is coupled to a spacecraft body at a plurality of attachment points and at least one of the plurality of force sensors is integrated at each of the attachment points. In one embodiment, the force sensors are piezoelectric transducers. In another embodiment, the control assembly is coupled to the spacecraft body at four attachment points. In yet another embodiment, each of the force sensors is preloaded by a bolt that attaches the attitude control assembly to the spacecraft body.

Abstract: Methods and structures are provided for reducing pointing errors &zgr; of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes &bgr; and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location &lgr; and which measures received signal strengths &agr;. Pointing errors &zgr; of the transmit beams are then determined from the estimated pointing attitudes &bgr;, the terminal location &lgr; and the signal strengths &agr; and the pointing errors &zgr; are subsequently reduced by revising the pointing attitudes &bgr;. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

Abstract: Payload performance is optimized by determining yaw trajectory employing a method which develops a mathematical expression to define the payload in terms of ‘n’ location(s) on the earth; determining the pointing error of the ‘n’ location(s); combining the error so as to product a single performance parameter and minimizing the value of the performance parameter by appropriately varying yaw.

Abstract: Methods and structures are provided for reducing pointing errors &zgr; of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes &bgr; and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location &lgr; and which measures received signal strengths &agr;. Pointing errors &zgr; of the transmit beams are then determined from the estimated pointing attitudes &bgr;, the terminal location &lgr; and the signal strengths &agr; and the pointing errors &zgr; are subsequently reduced by revising the pointing attitudes &bgr;. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

Abstract: A method for correcting differences in measurements between sensors. Misalignment of a roll error of a sun sensor alignment is estimated with respect to a reference roll value measured by an earth sensor. Sun sensor assembly elevation angle residual is calculated utilizing the estimated sun sensor assembly roll misalignment. A yaw attitude of the spacecraft is updated based upon the calculated sun sensor assembly elevation residual.

Abstract: A terrestrial C/A code GPS receiver system derives along-track position information while tracking as few as two GPS satellites by use of conventional altitude hold and a cross-track hold mode in which the maximum expected deviation of the vehicle from the expected track is estimated by, for example, knowledge or prediction of the width of the roadway or other track. To maintain accuracy, cross-track hold is alternated with clock hold to update the cross-track estimate when changes in vehicle direction are detected or when a predetermined period has elapsed.

Abstract: By using the GPS satellite transmitted signals that are tracked on a satellite and those that should be tracked but are not due to the attitude of the satellite and rotating the satellite, two estimations of satellite attitude are made that are used to change the satellite attitude so that all the GPS signals are tracked.

Abstract: A system and method for correcting pointing errors induced by an inclined orbit (14) for a satellite (20) that is adapted to be in an orbit having zero inclination (12). The present invention generates a yaw correcting cosine rate command (34) that is integrated (36) by a steering law having input parameters dependent upon the angle of inclination, &THgr;, to derive a sinusoidal yaw offset. The present invention also generates a roll correcting cosine rate command (54) that is integrated (56) according to a steering law having input parameters dependent upon the angle of inclination, &THgr;, to derive a sinusoidal roll offset.

Abstract: A two-step method is used to reconfigure beams among different orbital slots for a satellite system. The satellite is biased at one or more orbital slots for a back-up mission, while it looks at the sub-satellite point for the primary mission. Body steering is achieved using pitch and roll biases. The main reflector of the antenna is gimballed in order to steer the beams to different locations for the back-up mission. Beam size is controlled through the use of different sized reflectors and by varying the feed size. Different sized beams are interleaved among multiple reflectors.

Abstract: A method, an apparatus and a computer program product are provided for accurately determining the vertical speed of an aircraft in a manner independent of signals provided by an air data computer, an inertial reference system and an inertial navigation system. Initially, a first vertical velocity of the aircraft is determined based upon a pressure altitude value associated with the aircraft. A second vertical velocity of the aircraft is also obtained from a GPS receiver carried by the aircraft. The first and second vertical velocities are then combined to determine the vertical speed of the aircraft. In this regard, the first and second vertical velocities are combined by complimentarily filtering the first and second vertical velocities. More particularly, the first vertical velocity is typically low pass filtered to remove high frequency noise that is attributable to the relatively low resolution of the first vertical velocity value.

Abstract: A terrestrial C/A code GPS receiver system derives along track position information while tracking as few as two GPS satellites by use of conventional altitude hold and a cross track hold mode in which the maximum expected deviation of the vehicle from the expected track is estimated by, for example, knowledge or prediction of the width of the roadway or other track. To maintain accuracy, cross track hold is alternated with clock hold to update the cross track estimate when changes in vehicle direction are detected or when a predetermined period has elapsed.

Abstract: An apparatus for regulating or controlling a satellite includes: at least one sensor for detecting reference targets such as stars, which is connected to arrangements for selecting and determining the position of reference targets, and to an arrangement for estimating model parameters of the satellite and of external interferences; a memory for storing a reference target catalog and a reference trajectory; a regulating unit for regulating the position of the satellite; and a filter that is connected to the arrangement for position determination of the reference targets, the arrangements for estimating the model parameters, the memory and the regulating unit.

Abstract: A system and method for improving the accuracy of altitude determinations in an inertial navigation system. The system utilizes pressure measurements which are taken by a barometric altimeter and converted into an estimated pressure altitude using any known pressure-to-altitude conversion. A pressure correction value is then generated using a correction value generating formula that is a function of altitude. The pressure correction value is then multiplied by a pressure offset value for the barometric altimeter to generate a pressure offset error for the barometric altimeter. This pressure offset error is used in the present invention to modify the pressure altitude estimation in order to generate an altitude determination having an improved accuracy. The present invention further determines an amount of observation noise in the barometric altimeter that is a function of pressure noise and altitude, where the altitude estimation is further modified to account for the observation noise.

Abstract: Techniques for monitoring and controlling yawing of a GPS satellite in an orbit that has an eclipsing portion out of the sunlight based on the orbital conditions of the GPS satellite. In one embodiment, a constant yaw bias is generated in the attitude control system of the GPS satellite to control the yawing of the GPS satellite when it is in the shadow of the earth.

Abstract: The apparatus of the present invention uses radar altimeter measurements and stored terrain altitude profiles to provide pre-filtered observations to a Kalman filter for estimating barometric offset at the airport runway, and barometric scale factor for offsets above the runway. These offsets are used with the smoothed baro-inertial output from an inertial reference system to provide 3 dimensional constant rate of descent approach procedures to replace non-precision approach procedures based on constant barometric altitude step approaches. The horizontal positions used as reference for the stored terrain altitude profiles are obtained from a prior art navigation apparatus. The integrity of all measurements is assured by using long term averages of the Kalman filter residuals to detect failures. In addition, the estimated baro offset at the runway is compared for consistency with the baro offset obtained by the pilot from the airport by radio.