Method and system for tracking a moving station or target in free space communications
First Claim
1. A method of tracking a station in relative movement comprising the steps of:
- calculating a mathematical model of a travel path of the station;
determining a time interval between when the station passed a designated point along the travel path and a future time;
determining a future position of the station based on the time interval and the mathematical model; and
re-pointing an optical terminal to stare at the future position, wherein the optical terminal is configured to carry out free space optical communications with the station once the station is acquired, for the exchange of data between the station and optical terminal.
9 Assignments
0 Petitions
Accused Products
Abstract
A method for target acquisition and tracking of a moving station or target (e.g., an unmanned aerial vehicle) for carrying out free space optical communications uses an “elapsed time”-based approach to determine the position of the moving station at any future time, based on the time difference since the moving station'"'"'s last known position. For example, the vehicle may be for purposes of reconnaissance, where the optical link provides a secure and high-bandwidth communications pathway between the moving station and a ground station. A mathematical model of the moving station'"'"'s expected periodic flight path is combined with position and time elements to accurately predict the future position of the moving station for target re-acquisition. The model is a cubic spline interpolation of known flight path waypoints. The system may also employ multiple waypoints in initial acquisition, by alternating acquisition attempts over several waypoints instead of “staring” at a single waypoint.
10 Citations
22 Claims
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1. A method of tracking a station in relative movement comprising the steps of:
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calculating a mathematical model of a travel path of the station; determining a time interval between when the station passed a designated point along the travel path and a future time; determining a future position of the station based on the time interval and the mathematical model; and re-pointing an optical terminal to stare at the future position, wherein the optical terminal is configured to carry out free space optical communications with the station once the station is acquired, for the exchange of data between the station and optical terminal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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13. A method of tracking a relatively moving station comprising the steps of:
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determining a time interval between when the station was at a last known position along a designated travel path and a future time; determining a future position of the station along the designated travel path based on the time interval; and re-pointing an optical terminal to stare at the future position, wherein the optical terminal is configured to carry out free space optical communications with the station once the station is acquired, for the exchange of data between the station and optical terminal. - View Dependent Claims (14, 15, 16, 17, 18)
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19. A method of free space optical communications with a station in relative movement, the method comprising the steps of:
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pointing an optical terminal to stare at a first of a plurality of known waypoints along a path of travel of the station; if an actual location of the station does not coincide with the first waypoint, repeatedly re-pointing the optical terminal to stare at different known waypoints until the actual location of the station coincides with a currently stared-at waypoint; and transmitting optical data signals to the station from the optical terminal. - View Dependent Claims (20)
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21. A method of tracking a station in relative movement comprising the steps of:
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calculating a mathematical model of a travel path of the station; determining a time interval between when the station passed a designated point along the travel path and a future time; determining a future position of the station based on the time interval and the mathematical model; re-pointing an optical terminal to stare at the future position; and carrying out continuous free space communications over the optical terminal with the station once the station is acquired, wherein the continuous free space communications include an exchange of data between the station and the optical terminal.
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22. A method of tracking a station in relative movement comprising the steps of:
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establishing a tracking lock on the station; calculating a mathematical model of a travel path of the station based on the tracking lock; determining a time interval between when the station passed a designated point along the travel path and a future time; determining a future position of the station based on the time interval and the mathematical model; re-pointing an optical terminal to stare at the future position; and re-acquiring the station after the tracking lock is lost based on the re-pointing, wherein the optical terminal is configured to carry out free space optical communications with the station once the station is acquired, for the exchange of data between the station and optical terminal.
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Specification