Systems, methods, and apparatus for space surveillance are disclosed herein. In one or more embodiments, the disclosed method involves scanning, by at least one sensor on at least one satellite in super-geostationary earth orbit (super-GEO), a raster scan over a field of regard (FOR). In one or more embodiments, the scanning is at a variable rate, which is dependent upon a target dwell time for detecting a target of interest. In at least one embodiment, the target dwell time is a function of a characteristic brightness of the target.

Systems, methods, and apparatus for space surveillance are disclosed herein. In one or more embodiments, the disclosed method involves scanning, by at least one sensor on at least one satellite in inclined super-geostationary earth orbit (super-GEO), a raster scan over a field of regard (FOR). In one or more embodiments, the scanning is at a variable rate, which is dependent upon a target dwell time for detecting a target of interest. In at least one embodiment, the target dwell time is a function of a range from at least one sensor to the target of interest and a function of a solar phase angle. In some embodiments, the axis of inclination of the inclined super-GEO is a function of the solar phase angle.

A satellite system operates at altitudes between 180 km and 350 km relying on vehicles including an engine to counteract atmospheric drag to maintain near-constant orbit dynamics. The system operates at altitudes that are substantially lower than traditional satellites, reducing size, weight and cost of the vehicles and their constituent subsystems such as optical imagers, radars, and radio links. The system can include a large number of lower cost, mass, and altitude vehicles, enabling revisit times substantially shorter than previous satellite systems. The vehicles spend their orbit at low altitude, high atmospheric density conditions that have heretofore been virtually impossible to consider for stable orbits. Short revisit times at low altitudes enable near-real time imaging at high resolution and low cost. At such altitudes, the system has no impact on space junk issues of traditional LEO orbits, and is self-cleaning in that space junk or disabled craft will de-orbit.

A satellite system operates at altitudes between 180 km and 350 km relying on vehicles including an engine to counteract atmospheric drag to maintain near-constant orbit dynamics. The system operates at altitudes that are substantially lower than traditional satellites, reducing size, weight and cost of the vehicles and their constituent subsystems such as optical imagers, radars, and radio links. The system can include a large number of lower cost, mass, and altitude vehicles, enabling revisit times substantially shorter than previous satellite systems. The vehicles spend their orbit at low altitude, high atmospheric density conditions that have heretofore been virtually impossible to consider for stable orbits. Short revisit times at low altitudes enable near-real time imaging at high resolution and low cost. At such altitudes, the system has no impact on space junk issues of traditional LEO orbits, and is self-cleaning in that space junk or disabled craft will de-orbit.

Described herein are spacecraft flight and mission managers and systems, methods, and computing apparatuses for dynamically maneuvering a spacecraft towards a target area for synthetic aperture radar (SAR) capture based on antenna availability. In an embodiment, a flight and mission manager obtains user inputs for a spacecraft mission related to a synthetic aperture radar request of a target area and maneuvers for a spacecraft to reach that target area. An orbit path is determined based on user inputs and telemetry of the spacecraft. A visibility schedule of antennas of a ground station provider is obtained corresponding to the orbit path. Then, a tasking plan is generated to perform the user inputs and maintain the orbit path.

A satellite (140) for operation in orbit around the earth comprises an ADCS (131, FIG. 1) configured for mechanically steering the satellite in the azimuth direction to prolong a dwell time (1105), during which a selected target is visible from the satellite, as the satellite orbits over the target. A processor at the ground station may be configured to process raw SAR data from any of the satellites described here. The raw SAR data may be processed in a number of ways to provide image information including but not limited to forming multilook images, compiling video sequences and colour coding images.

Systems, devices, methods, and computer-readable media for space vehicle sensor management. A method includes receiving, at a mission operations center (MOC), respective regional requests from respective regional schedulers, the respective regional requests indicating mission windows (MWs) and corresponding sensors to be operated in associated MWs, receiving, at the MOC, respective sensor plans from corresponding space vehicle operation centers (SVOCs), each sensor plan indicating MWs for which a given sensor is unavailable, generating, based on the regional requests and the sensor plans, a MW apportionment for each regional scheduler, the MW apportionment indicating MWs and corresponding sensors that a user associated with the regional scheduler has authorization to command the sensor, and providing the MW apportionment for the regional scheduler to the regional scheduler.

A design method of a trust region satellite-borne dual-base interference SAR system is provided, relating to the field of radar measurement. Firstly, error sources of the interference SAR system are classified and analyzed, phase errors caused by image decoherence are calculated according to wave positions, and an analytical expression of baseline-related errors is reserved; a maximum phase error caused by imaging processing and an electronic device are estimated; and a baseline error is estimated. Then, the phase errors and the baseline errors are converted into elevation errors through an elevation fuzzy number, thereby obtaining an analytical expression of the elevation errors and the baseline parameters (length and dip angle). With a relative height measurement accuracy index of the system as an optimization object, a feasible solution interval between the baseline length and the baseline dip angle of the system is solved through a trust region algorithm. A minimum value of the baseline length is corrected according to a flying-around safety distance of a dual-satellite formation. According to the method of the present disclosure, the design of the satellite-borne dual-base interference SAR system can be guided, so that the satellite-borne dual-base interference SAR system is ensured to carry out terrain elevation surveying and mapping tasks with high accuracy and high reliability.

A design method of a trust region satellite-borne dual-base interference SAR system is provided, relating to the field of radar measurement. Firstly, error sources of the interference SAR system are classified and analyzed, phase errors caused by image decoherence are calculated according to wave positions, and an analytical expression of baseline-related errors is reserved; a maximum phase error caused by imaging processing and an electronic device are estimated; and a baseline error is estimated. Then, the phase errors and the baseline errors are converted into elevation errors through an elevation fuzzy number, thereby obtaining an analytical expression of the elevation errors and the baseline parameters (length and dip angle). With a relative height measurement accuracy index of the system as an optimization object, a feasible solution interval between the baseline length and the baseline dip angle of the system is solved through a trust region algorithm. A minimum value of the baseline length is corrected according to a flying-around safety distance of a dual-satellite formation. According to the method of the present disclosure, the design of the satellite-borne dual-base interference SAR system can be guided, so that the satellite-borne dual-base interference SAR system is ensured to carry out terrain elevation surveying and mapping tasks with high accuracy and high reliability.

A system comprises an array of antennas suitable for intercepting electromagnetic waves, one or more sensors, wherein said one or more sensors are configured to provide data informative of a position of each of a plurality of the antennas over time, wherein each of a plurality of the antennas is linked to a non-rigid portion, thereby undergoing displacement upon displacement of the non-rigid portion, wherein data informative of the electromagnetic waves intercepted by the array and data informative of the position of the plurality of antennas over time are usable for determining data informative of at least one of a position and a direction of at least one emitter of the electromagnetic waves.