Radio frequency communication system
First Claim
1. A method of tracking a position of a radiofrequency (RF)-transmitting device based on RF signals transmitted by the RF-transmitting device, comprising the steps of:
- calculating a present position of a RF-transmitting device based on RF signals transmitted by the RF-transmitting device;
determining the present position of the RF-transmitting device is an invalid position when a distance between the present position of the RF-transmitting device and a previous position of the RF-transmitting device exceeds a tolerance value that varies according to a velocity of the RF-transmitting device;
recalibrating, in response to determining the present position of the RF-transmitting device is an invalid position, the present position of the RF-transmitting device by;
obtaining data from RF signals transmitted by the RF-transmitting device; and
identifying a plurality of candidate position solutions;
evaluating at least one of the plurality of candidate position solutions against the obtained data to search for an acceptable candidate position solution; and
when the evaluating finds an acceptable candidate position solution, tracking the RF-transmitting device using the acceptable candidate position solution as the present position of the RF-transmitting device.
2 Assignments
0 Petitions
Accused Products
Abstract
A system and method for recovering from a failure during the position tracking of an RF-transmitting device includes tracking the position of the radio frequency (RF) transmitting device based on RF signals emitted by the RF-transmitting device. If the tracking loses the position of the RF-transmitting device, new phase difference data are calculated from the RF signals transmitted by the RF-transmitting device and received at four or more antennas. A subset of candidate position solutions for evaluation is identified based on the new phase difference data. One or more of the candidate position solutions in the subset is evaluated to find an acceptable position solution. The tracking of the position of the RF-transmitting device resumes using the acceptable position solution.
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Citations
20 Claims
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1. A method of tracking a position of a radiofrequency (RF)-transmitting device based on RF signals transmitted by the RF-transmitting device, comprising the steps of:
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calculating a present position of a RF-transmitting device based on RF signals transmitted by the RF-transmitting device; determining the present position of the RF-transmitting device is an invalid position when a distance between the present position of the RF-transmitting device and a previous position of the RF-transmitting device exceeds a tolerance value that varies according to a velocity of the RF-transmitting device; recalibrating, in response to determining the present position of the RF-transmitting device is an invalid position, the present position of the RF-transmitting device by; obtaining data from RF signals transmitted by the RF-transmitting device; and identifying a plurality of candidate position solutions; evaluating at least one of the plurality of candidate position solutions against the obtained data to search for an acceptable candidate position solution; and when the evaluating finds an acceptable candidate position solution, tracking the RF-transmitting device using the acceptable candidate position solution as the present position of the RF-transmitting device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A position tracking system for tracking a position of a radiofrequency (RF)-transmitting device based on RF signals transmitted by the RF-transmitting device, the system comprising:
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a network of four or more spatially separated antennas fixed at different locations, the four or more antennas receiving RF signals sent from the RF-transmitting device; and a data processor configured to calculate a present position of a RF-transmitting device based on the RF signals received by the four or more antennas, the data processor being further configured to; determine the present position of the RF-transmitting device is an invalid position when a distance between the present position of the RF-transmitting device and a previous position of the RF-transmitting device exceeds a tolerance value that varies according to a velocity of the RF-transmitting device, recalibrate, in response to determining the calculated present position of the RF-transmitting device is an invalid position, the present position of the RF-transmitting device by; obtaining data from RF signals transmitted by the RF-transmitting device; identifying a plurality of candidate position solutions; and evaluating at least one of the plurality of candidate position solutions against the obtained data to search for an acceptable candidate position solution; and track the RF-transmitting device using the acceptable candidate position solution as the present position of the RF-transmitting device when the evaluating finds an acceptable candidate position solution. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
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18. A method of tracking a position of a radiofrequency (RF)-transmitting device based on RF signals transmitted by the RF-transmitting device, comprising the steps of:
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calculating a present three-dimensional (3D) position of a RF-transmitting device based on RF signals transmitted by the RF-transmitting device; calculating a distance between the present 3D position of the RF-transmitting device and a previously calculated 3D position of the RF-transmitting device; determining the present 3D position of the RF-transmitting device is an invalid position when the calculated distance exceeds a tolerance that varies according to a velocity of the RF-transmitting device; recalibrating, in response to determining the present 3D position of the RF-transmitting device is an invalid position, the present 3D position of the RF-transmitting device by; obtaining data from RF signals transmitted by the RF-transmitting device; calculating a plurality of candidate 3D position solutions; evaluating at least one of the candidate 3D position solutions against the obtained data to search for an acceptable candidate 3D position solution; and when the evaluating finds an acceptable candidate 3D position solution, tracking the RF-transmitting device using the acceptable candidate 3D position solution as the present 3D position of the RF-transmitting device. - View Dependent Claims (19, 20)
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Specification