Method for an improved linear least squares estimation of a mobile terminal's location under LOS and NLOS conditions and using map information

Patent 8219111 Issued on July 10, 2012. Estimated Expiration Date:

September 2, 2028. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Assignee

NTT Docomo

Application

No. 12202611 filed on 09/02/2008

US Classes:

455/456.1Location monitoring , 342/357.38

Examiners

Primary: Addy, Anthony
Assistant: Behnamian, Shahriar

Attorney, Agent or Firm

Haynes & Boone, LLP.

International Class

H04W 4/00

Abstract

A linear least squares (LLS) estimator provides a low complexity estimation of the location of a mobile terminal (MT), using one of the fixed terminals (FTs) as a reference FT to derive a linear model. A method for selecting a reference FT is disclosed, which improves the location accuracy relative to an arbitrary approach to selecting the reference FT. In addition, a covariance-matrix based LLS estimator is proposed in line-of-sight (LOS) and non-LOS (NLOS) environments to further provide accuracy, taking advantage of the correlation of the observations. Different techniques for selecting the reference FT under non-LOS (NLOS) conditions are disclosed. A map-based two-stage LLS estimator assists in selecting the reference FT under NLOS conditions.

Other References

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