61 results about "Earth's orbit" patented technology

A receiver for position-determining ranging signals transmitted by earth-orbiting satellites uses a set of accumulators, each of which accumulates signal samples corresponding with a position along the rising edges of incoming PRN pulses. An MMT processor calculates the rising edges of the direct path component of the received signal, selects the accumulator whose content correspond to a reference value related to the pulse height of the direct path component and compares the timing of the samples in that accumulator with the timing of the reference value on a reference pulse.

A method of locating a terrestrial emitter of electromagnetic radiation in the midst of a plurality of emitters in a satellite in orbit about the earth which utilizes a location estimation and location probability determination process with respect to each possible emitter site and its corresponding error region and then using both feedback and feed forward interaction between location and phase ambiguity resolution processes to generate resolved phase from emitter location, update emitter location or some or all of the emitters, and subsequently utilizing the probabilities thus determined to produce a single estimate of the desired emitter's location.

High priority data and low priority digital data are transmitted as primary and secondary data in hierarchically modulated, orthogonal frequency division multiplexing (OFDM) from an earth-orbiting satellite. To enable the transmitter amplifier to be operated with less back-off from saturation without clipping, the low priority OFDM symbols have fewer samples than the high priority OFDM symbols, and the high priority samples on which the low priority samples are superimposed are selected according to a first deterministic rule using sample power comparisons of the high priority samples to concentrate the low priority samples on those high priority samples having lower (optimally, the lowest) sample power. The low priority samples are distributed on the selected high priority samples according to a second deterministic rule relating the original low priority sample order to the original high priority sample order.

A method for controlling the orbit of a satellite in earth orbit. The orbit of the satellite is controlled by commanding, according to a maneuver plan, a propulsion system having at least one thruster and a transporter to move the propulsion system. The maneuver plan includes at least two orbit-control maneuvers. The thrust powers of the propulsion system during the two orbit control maneuvers have respective thrust directions that are not parallel in an inertial frame of reference. Each thrust power is determined to simultaneously control the inclination and the position of the orbit of the satellite as well as to form a momentum that is suitable for unloading a device for storing angular momentum of the satellite in a plane orthogonal to the direction of thrust of the thrust power.

Pulsed detonation engines (PDEs) are adapted for use in reaction control systems (RCS), such as thrusters for orbital correction and control (e.g., for earth-orbiting satellites), divert thrust generation and control for space-based interceptor devices, and for missile trajectory correction and motion control. According to one aspect of the invention, PDEs are adapted for motion control of so-called “kill vehicles,” which are small devices, typically launched from satellites, for strategic missile defense.

A method for transporting people and cargo from the surface of the Earth to orbit around the Earth is disclosed. The present invention uses a series of lighter-than-air vehicles to allow for a far safer and less strenuous trip to orbit than using current rocket-based technology. The high altitude atmospheric airship is flown from the ground to the upper atmosphere, where it docks with the buoyant transfer station, and from there, the people and cargo transfer to an orbital airship for the remainder of the trip to orbit. The orbital airship returns to the station for another transfer back to the atmospheric airship for the return back to the surface of Earth.

A space-based server network architecture (1) which permits on demand transfer of mission and control data between client satellites (14) in an orbit about earth and an earth station (20, 22, 24, 26) irrespective of the location of the client satellite (14) relative to the earth station (20, 22, 24, 26). The architecture includes a plurality of server satellites (10) located spaced apart in a earth orbit above the orbit of the client satellites (14). The server satellites (10) provide substantially total world-wide communications coverage to and connectivity with designated and authorized earth stations (20, 22, 24, 26) and the plurality of client satellites (14). Each server satellite (10) includes: a communications downlink (18, 18a, 18b) for providing intercommunication with designated and authorized earth stations within its field of view; communications crosslinks (12, 12a, 12b) for providing intercommunications with other server satellites within its field of view; and communications links (16, 16a, 16b) for providing intercommunication with a client satellite within its field of view. Client satellite control data originating from an earth station is passed directly to an accessible server satellite, which then passes the control data either directly to the intended client satellite if within its communications field of view, or forwards the control data to a server satellite having direct communications access to the intended client satellite. Mission data from a client satellite can at any time be transmitted to a designated earth station, irrespective of its location on earth, by transmitting first to a server satellite within its communication field of view, where the mission data is then either downlinked directly to the designated earth station if within its communications field of view, or transmitting to a server satellite having communications downlink access to the designated earth station.

A method for acquiring images using a constellation of satellites in non-geosynchronous terrestrial orbit. The satellites include respective devices for inter-satellite communication. An aggregate of work plans intended for various satellites is formed. A ground station transmits the aggregate intended for one satellite. The satellite receiving the aggregate retransmits the aggregate intended for at least one other satellite from the ground station. Each satellite receiving the aggregate from another satellite re-transmits the aggregate intended for at least one other satellite. Each satellite recovers its work plan from the aggregate received.

Techniques for data transmission including receiving, at a geostationary earth orbiting satellite, forward-direction user data via a forward optical link; transmitting, by the geostationary earth orbiting satellite via multiple radio frequency (RF) spot beams, the forward-direction user data received via the forward optical link; receiving, at a stratospheric high-altitude communication device, forward-direction user data via multiple concurrent forward RF feeder links; transmitting, by the stratospheric high-altitude communication device via the forward optical link, the forward-direction user data received via the forward RF feeder links; transmitting, by each of multiple ground-based feeder RF terminals at a same RF feeder site, a respective one of the forward RF feeder links. At least 95% of forward feeder data throughput for all of the forward RF service link transmissions by the satellite is carried via the forward optical link and the forward RF feeder links.

Embodiments of the present invention characterizing the uncertainty of the orbital state of an Earth-orbiting space object hereof using a Gauss von Mises probability density function defined on the n+1 dimensional cylindrical manifold n×. Additionally, embodiments of the present invention can include transforming a Gauss von Mises distribution under a diffeomorphism and approximating the output as a Gauss von Mises distribution. Embodiments of the present invention can also include fusing a prior state represented by a Gauss von Mises distribution with an update report, wherein the update can be either another Gauss von Mises distribution of the same dimension as the prior or an observation related to the prior by a stochastic measurement model. A Gauss von Mises distribution can be calculated from a plurality of reports, wherein the reports are either Gauss von Mises distributions or observations related to the state space by a stochastic measurement model.