SYSTEM AND METHOD OF UMTS UE LOCATION USING UPLINK DEDICATED PHYSICAL CONTROL CHANNEL AND DOWNLINK SYNCHRONIZATION CHANNEL
First Claim
1. A method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), the method comprising the steps of;
(a) collecting a plurality of signal samples from a first wireless device and a second wireless device by one or more LMUs in a first search window;
(b) determining a first time of arrival (“
TOA”
) from the plural signal samples;
(c) determining a second search window as a function of the first TOA;
(d) determining a second TOA from the plural signal samples in the second search window;
(e) determining a range estimate of the first wireless device; and
(f) determining an estimated location of the first wireless device as a function of the first TOA, the second TOA, or the range estimate and second TOA.
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Accused Products
Abstract
A system and method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“LMUs”). A set of signal samples from a first wireless device and a second wireless device may be collected by one or more LMUs in a search window. A first time of arrival (“TOA”) is determined, and a second search window is estimated as a function of the first TOA. A second TOA may be determined within the second search window at a second node or one of the LMUs from the set of signal samples. A range estimate of the wireless device may then be determined, and an estimated location of the wireless device may be determined as a function of the first uplink TOA, the second uplink TOA, or the range estimate and second TOA.
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Citations
38 Claims
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1. A method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), the method comprising the steps of;(a) collecting a plurality of signal samples from a first wireless device and a second wireless device by one or more LMUs in a first search window; (b) determining a first time of arrival (“
TOA”
) from the plural signal samples;(c) determining a second search window as a function of the first TOA; (d) determining a second TOA from the plural signal samples in the second search window; (e) determining a range estimate of the first wireless device; and (f) determining an estimated location of the first wireless device as a function of the first TOA, the second TOA, or the range estimate and second TOA. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
- LMU”
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19. A method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), the method comprising the steps of;(a) collecting a set of signal samples from a first wireless device and a second wireless device by one or more LMUs in a search window determined as a function of a first uplink time of arrival (“
TOA”
) from a first node;(b) determining a second uplink TOA at a second node or the one or more LMUs from the set of signal samples; (c) determining a range estimate of the wireless device; and (d) determining an estimated location of the wireless device as a function of the first uplink TOA, the second uplink TOA, or the range estimate and second TOA. - View Dependent Claims (20, 21, 22, 23, 24)
- LMU”
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25. A method for estimating a location of a wireless device in a communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), comprising the steps of;(a) collecting signal samples from the wireless device by one or more LMUs; (b) detecting a time of arrival (“
TOA”
) from the signal samples, the detecting including;(i) segmenting the collected signal samples to a predetermined length, (ii) determining an ambiguity function or correlation for each segment, and (iii) adding the ambiguity functions or correlations to detect a TOA; and (c) determining an estimated location of the wireless device as a function of the TOA, wherein a demeaned peak to standard deviation ratio is applied to the added ambiguity functions or correlations. - View Dependent Claims (26, 27)
- LMU”
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28. A method for estimating a location of a wireless device in a communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), comprising the steps of;(a) collecting signal samples from the wireless device by one or more LMUs; (b) detecting a time of arrival (“
TOA”
) from the signal samples, the detecting including;(i) determining a mixing product of the collected signal samples, (ii) decimating the mixing product, (iii) segmenting the decimated product to predetermined lengths, (iv) determining ambiguity functions for each segment, and (v) adding the ambiguity functions to detect a TOA; and (c) determining an estimated location of the wireless device as a function of the TOA, wherein a demeaned peak to standard deviation ratio is applied to the added ambiguity functions. - View Dependent Claims (29, 30)
- LMU”
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31. In a communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), a method for estimating a location of a wireless device, the method comprising collecting signal samples from the wireless device by one or more LMUs, detecting a time of arrival (“
TOA”
) from the signal samples, and determining an estimated location of the wireless device as a function of the TOA, the improvement wherein the TOA is detected without regard to noise and gain variation in the collected signal samples.
- LMU”
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32. A method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“
- LMU”
), the method comprising the steps of;(a) collecting a set of signal samples from a first wireless device and a second wireless device by one or more LMUs in a search window determined as a function of a first uplink time of arrival (“
TOA”
) from a first node;(b) detecting a second uplink TOA at a second node or LMU from the set of signal samples by a plurality of non-coherent additions of ambiguity functions; (c) determining a range estimate of the wireless device; and (d) determining an estimated location of the wireless device as a function of the first uplink TOA, the second uplink TOA, or the range estimate and second TOA. - View Dependent Claims (33, 34, 35, 36, 37, 38)
- LMU”
Specification