METHOD TO ESTIMATE AND COMPENSATE FOR NLOS BIAS IN TIME DIFFERENCE OF ARRIVAL ESTIMATE
First Claim
1. A method for compensating for non-line-of-sight (“
- NLOS”
) bias in time difference of arrival (“
TDOA”
) estimate between a first anchor and a second anchor in a network having an obstacle in the line-of-sight therebetween, the method comprising;
transmitting a first packet from a first anchor;
indirectly receiving the first packet by a second anchor, then transmitting a second packet by the second anchor;
indirectly receiving the second packet by the first anchor;
receiving the first packet and the second packet by a mobile node;
estimating the true fly-time of the first or second packets between the first anchor and the second anchor;
estimating the bias in time of flight of the first or second packets between the first anchor and the second anchor;
estimating the time difference of arrival at the mobile device between a direct path and an indirect path;
correcting the NLOS bias in the time difference of arrival estimated at the mobile device.
3 Assignments
0 Petitions
Accused Products
Abstract
Devices, systems, and method for compensating for non-line-of-sight (“NLOS”) bias in time difference of arrival (“TDOA”) estimates between a first anchor and a second anchor in a network having an obstacle in the line-of-sight therebetween are provided. The systems and methods include transmitting a first packet from a first anchor; indirectly receiving the first packet by a second anchor, then transmitting a second packet by the second anchor; indirectly receiving the second packet by the first anchor; and receiving the first packet and the second packet by a mobile node. The true fly-time of the first or second packets between the first anchor and the second anchor and the bias in time of flight of the first or second packets between the first anchor and the second anchor are estimated. The time difference of arrival at the mobile device between a direct path and an indirect path is further estimated and the NLOS bias in the time difference of arrival estimated at the mobile device is corrected.
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Citations
20 Claims
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1. A method for compensating for non-line-of-sight (“
- NLOS”
) bias in time difference of arrival (“
TDOA”
) estimate between a first anchor and a second anchor in a network having an obstacle in the line-of-sight therebetween, the method comprising;transmitting a first packet from a first anchor; indirectly receiving the first packet by a second anchor, then transmitting a second packet by the second anchor; indirectly receiving the second packet by the first anchor; receiving the first packet and the second packet by a mobile node; estimating the true fly-time of the first or second packets between the first anchor and the second anchor; estimating the bias in time of flight of the first or second packets between the first anchor and the second anchor; estimating the time difference of arrival at the mobile device between a direct path and an indirect path; correcting the NLOS bias in the time difference of arrival estimated at the mobile device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
- NLOS”
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15. A method to compensate for non-line-of-sight (“
- NLOS”
) bias in a time difference of arrival estimate, using an uplink time difference of arrival (“
UL-TDOA”
) scheme, the method comprising;transmitting a first packet by a mobile device; receiving the first packet by at least one first anchor and then transmitting a second packet by the at least one first anchor; receiving the first packet and the second packet by at least one second anchor in range of the mobile device and at least one first anchor; estimating the time differences of arrival at the at least one second anchor; and correcting the time differences of arrival at the at least one second anchor by subtracting the NLOS bias between the at least one first anchor and at least one second anchor. - View Dependent Claims (16, 17)
- NLOS”
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18. A method to compensate for the non-line-of-sight (“
- NLOS”
) bias in a beacon synchronized time difference of arrival (“
BS-TDOA”
) estimate, the method comprising;transmitting a first packet by a first anchor; receiving the first packet by a mobile node and then transmitting a second packet by the mobile node; receiving the first packet and the second packet by at least one second anchor that is within range of the first anchor and the mobile node; and measuring the time differences of arrival between a direct packet transmission path and an indirect packet transmission path by the at least one second node; correcting the time differences of arrival with an estimated bias of fly-time between the first anchor and at least one second anchor. - View Dependent Claims (19, 20)
- NLOS”
Specification