NETWORK AIDED TERRESTRIAL TRIANGULATION USING STARS (NATTS)

• US 20090140915A1
• Filed: 12/30/2008
• Published: 06/04/2009
• Est. Priority Date: 06/03/2005
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: TeraHop Networks Incorporated
• Inventors: TWITCHELL, Robert W. JR.
• Granted Patent: US 7,822,551 B2
• Time in Patent Office: Days
• US Class Current: 342/357.400
• CPC Class Codes: G01C 21/025 with the use of startrackers

Abstract

A method for determining a terrestrial location of an apparatus that is deployed in a generally known geographical region includes capturing, by the apparatus, an earthbound image of the sky from a terrestrial location at an identified time; communicating, by the apparatus, data representative of the captured earthbound image of the sky; and determining the terrestrial location of the apparatus based on the data communicated by the apparatus by comparing the captured earthbound image of the sky to a master mapping of the sky relative to the surface of the Earth.

Claims

1-20. -20. (canceled)

21. A system, comprising:

at least one asset tracking device, the asset tracking device including a communications module, a processing and storage module coupled to the communications module, and a location module coupled to the processing and storage module;

a network access point, wirelessly coupled to the at least one asset tracking device; and

a local positioning system comprising a plurality of reference tags, each of the reference tags having its known position coordinates stored therein, the reference tags wirelessly coupled to receive signals transmitted from the at least one asset tracking device, and to transmit signals to the at least one asset tracking device;

wherein the at least one asset tracking device is operable to determine that its location module is unable to determine position coordinates from GPS signals, is further operable to search for one or more reference tags of the local positioning system, to communicate with the local positioning system so as to gather the information necessary to compute its position coordinates; and

wherein the at least one asset tracking device is an RFID tag attached to an item to be tracked; and

wherein one of the reference tags includes an imaging component configured to capture an earthbound image of the sky for calculating its position coordinates.

22. The system of claim 21, further comprising a server disposed in communication with the network access point, and wherein the reference tag that captures the earthbound image and the server are configured such that:

(a) the reference tag communicates, to the server using the network access point, data representative of the captured earthbound image of the sky and an identified time at which the image was captured;

(b) the server determines the terrestrial location of the reference tag based on the data communicated by the reference tag by comparing the captured earthbound image of the sky to a master mapping of the sky relative to the surface of the Earth, including,

(i) manipulating the master map of the sky into a model in which the shape of a sphere is disposed above the surface of the Earth,

(ii) projecting latitude and longitude lines perpendicularly from the surface of the Earth onto the master mapping of the sky,

(iii) comparing the captured earthbound image to said manipulated master mapping of the sky, and

(iv) matching said captured earthbound image to said manipulated master mapping of the sky and reading the latitude and longitude values on said manipulated master map of the sky at the point where said captured earthbound image most closely matches said manipulated master map of the sky, thereby determining the terrestrial location from which the earthbound image was captured by the reference tag; and

(c) the server communicates, to the reference tag, the determined terrestrial location of the reference tag.

23. The system of claim 21, wherein the asset tracking device comprises a remote sensor interface.

24. A system, comprising:

an asset tracking device including a transceiver for sending and receiving communications, a processor and memory coupled to the transceiver for wireless communications, and a GPS receiver coupled to the processor and memory for computing position coordinates of the asset tracking device;

a network access point wirelessly coupled to the asset tracking device; and

a plurality of wireless devices, each wireless device having its known position coordinates stored therein, the wireless devices wirelessly coupled to receive signals transmitted from the asset tracking device, and to transmit signals to the asset tracking device;

wherein the asset tracking device is operable to determine that its GPS receiver is unable to determine position coordinates from GPS signals, is further operable to search for one or more of the wireless devices, to communicate with the wireless devices so as to gather information necessary to compute its position coordinates;

wherein the asset tracking device includes a radio frequency identification for an item to be tracked, with which item the asset tracking device is associated; and

wherein one of the wireless devices includes an imaging component configured to capture an earthbound image of the sky for calculating its position coordinates.

25. The system of claim 24, further comprising a server disposed in communication with the network access point, and wherein the wireless device that captures the earthbound image and the server are configured such that:

(a) the wireless device communicates, to the server using the network access point, data representative of the captured earthbound image of the sky and an identified time at which the image was captured;

(b) the server determines the terrestrial location of the wireless device based on the data communicated by the wireless device by comparing the captured earthbound image of the sky to a master mapping of the sky relative to the surface of the Earth, including,

(i) manipulating the master map of the sky into a model in which the shape of a sphere is disposed above the surface of the Earth,

(ii) projecting latitude and longitude lines perpendicularly from the surface of the Earth onto the master mapping of the sky,

(iii) comparing the captured earthbound image to said manipulated master mapping of the sky, and

(iv) matching said captured earthbound image to said manipulated master mapping of the sky and reading the latitude and longitude values on said manipulated master map of the sky at the point where said captured earthbound image most closely matches said manipulated master map of the sky, thereby determining the terrestrial location from which the earthbound image was captured by the reference tag; and

(c) the server communicates, to the wireless device, the determined terrestrial location of the wireless device.

26. The system of claim 24, wherein the asset tracking device comprises a remote sensor interface.

29. The system of claim 24, wherein the asset tracking device comprises a remote sensor interface.

27. A system, comprising:

an asset tracking device including a transceiver for sending and receiving communications, a processor and memory coupled to the transceiver for wireless communications, and a GPS receiver coupled to the processor and memory for computing position coordinates of the asset tracking device;

a network access point wirelessly coupled to the asset tracking device; and

a plurality of wireless devices, each wireless device wirelessly coupled to receive signals transmitted from the asset tracking device, and to transmit signals to the asset tracking device;

wherein the asset tracking device is operable, when the asset tracking device is unable to determine its position coordinates from GPS signals, to communicate with one or more of the wireless devices so as to gather information necessary to compute its position coordinates, such information including the respective position coordinates of the one or more wireless devices;

wherein the asset tracking device includes a radio frequency identification for an item to be tracked, with which item the asset tracking device is associated; and

wherein one of the wireless devices includes an imaging component configured to capture an earthbound image of the sky for calculating its position coordinates.

28. The system of claim 27, further comprising a server disposed in communication with the network access point, and wherein the wireless device that captures the earthbound image and the server are configured such that:

(a) the wireless device communicates, to the server using the network access point, data representative of the captured earthbound image of the sky and an identified time at which the image was captured;

(b) the server determines the terrestrial location of the wireless device based on the data communicated by the wireless device by comparing the captured earthbound image of the sky to a master mapping of the sky relative to the surface of the Earth, including,

(i) manipulating the master map of the sky into a model in which the shape of a sphere is disposed above the surface of the Earth,

(ii) projecting latitude and longitude lines perpendicularly from the surface of the Earth onto the master mapping of the sky,

(iii) comparing the captured earthbound image to said manipulated master mapping of the sky, and

(iv) matching said captured earthbound image to said manipulated master mapping of the sky and reading the latitude and longitude values on said manipulated master map of the sky at the point where said captured earthbound image most closely matches said manipulated master map of the sky, thereby determining the terrestrial location from which the earthbound image was captured by the reference tag; and

(c) the server communicates, to the wireless device, the determined terrestrial location of the wireless device.