US6014102A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for calibrating location finding equipment within a communication system
Assignee: Google Technology Holdings LLC
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Filing: 1998-04-17
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Granted: 2000-01-11
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Expires: 2018-04-17
Abstract
Abstract Error vectors are added to any position estimate determined by Location finding equipment (LFE) in order to give a corrected position estimate. Error vectors are determined utilizing calibration terminals (114), which are roaming vehicles that move throughout the communication system's (100) coverage area. Each calibration terminal (114) comprises a remote unit (113) coupled with an independent position determining system (167) such as a Global Positioning System (GPS) receiver. Error vectors are determined by periodically polling calibration terminals (114). In response, each terminal (114) sends back a reply message containing their actual, independently determined location, along with periodically broadcasting a known sequence at increased power utilized by the LFE in determining a position estimate of the calibration terminal (114). The difference between the actual, and LFE determined position estimates are utilized in calculation of error vectors.
Inventors
- 👤 James Edward Mitzlaff
- 👤 John Duncan Toone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:51
CPC Classifications
G; G01; G01S; G01S5/00; G01S5/02; G01S5/0205; G01S5/021; G01S5/0244; G01S1/00; G01S1/02; G01S1/022; G01S19/00; G01S19/01; G01S19/13; G01S19/14
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
82 words
A method for calibrating location finding equipment within a communication system, the method comprising the steps of: receiving an independently transmitted first location of a mobile unit; determining, via the location finding equipment, a second location of the mobile unit; determining an error vector based on the first and the second location; determining, via the location finding equipment, a location of a remote unit; and modifying the location of the remote unit with the error vector to produce a calibrated location estimate.
Claim 2
Independent Claim
82 words
A method for calibrating location finding equipment within a communication system, the method comprising the steps of: receiving an independently transmitted first location of a mobile unit; determining, via the location finding equipment, a second location of the mobile unit; determining an error vector based on the first and the second location; determining, via the location finding equipment, a location of a remote unit; and modifying the location of the remote unit with the error vector to produce a calibrated location estimate.
Claim 3
Dependent Claim
59 words
The method of claim 1 wherein the step of determining via the location finding equipment, the second location of the mobile unit and the location of the remote unit comprises the step of determining a location via any combination of a Time of Arrival (TOA), Time Difference of Arrival (TDOA), or a Angle of Arrival (AOA) method of location.
Claim 4
Dependent Claim
29 words
The method of claim 2 further comprising the step of broadcasting a power-up function (PUF) to aid in determining the second location and the location of the remote unit.
Claim 5
Dependent Claim
53 words
The method of claim 1 wherein the step of modifying the location of the remote unit with the error vector comprises the step of modifying the location of the remote unit with a plurality of error vectors determined with mobile units having a closest known location to the location of the remote unit.
Claim 6
Dependent Claim
23 words
The method of claim 1 further comprising the step of calculating an uncertainty in the calibrated location estimate based on the error vector.
Claim 7
Dependent Claim
34 words
The method of claim 1 wherein the step of receiving the independently transmitted first location of the mobile unit comprises the step of receiving a Global Positioning System (GPS) measurement from the mobile unit.
Claim 8
Independent Claim
131 words
A method for calibrating location finding equipment within a communication system, the method comprising the steps of: receiving a plurality of independently transmitted first locations of a plurality of calibration units; determining, via the location finding equipment, a second plurality of locations of the plurality of calibration units; determining a plurality of error vectors based on the plurality of first and second locations; storing the plurality of error vectors along with the plurality of second locations of the calibration units; determining, via the location finding equipment, a location of a remote unit; retrieving the subset of the plurality of error vectors from the stored plurality of error vectors; and modifying the location of the remote unit with the subset of the plurality of error vectors to produce a calibrated location estimate.
Claim 9
Independent Claim
131 words
A method for calibrating location finding equipment within a communication system, the method comprising the steps of: receiving a plurality of independently transmitted first locations of a plurality of calibration units; determining, via the location finding equipment, a second plurality of locations of the plurality of calibration units; determining a plurality of error vectors based on the plurality of first and second locations; storing the plurality of error vectors along with the plurality of second locations of the calibration units; determining, via the location finding equipment, a location of a remote unit; retrieving the subset of the plurality of error vectors from the stored plurality of error vectors; and modifying the location of the remote unit with the subset of the plurality of error vectors to produce a calibrated location estimate.
Claim 10
Dependent Claim
62 words
The method of claim 7 wherein the step of determining via the location finding equipment, the second plurality of locations of the plurality of calibration units, and the location of the remote unit comprises the step of determining a location via any combination of a Time of Arrival (TOA), Time Difference of Arrival (TDOA), or Angle of Arrival (AOA) method of location.
Claim 11
Dependent Claim
29 words
The method of claim 8 further comprising the step of broadcasting a power-up function (PUF) to aid in determining the second locations and the location of the remote unit.
Claim 12
Dependent Claim
75 words
The method of claim 7 wherein the step of modifying the location of the remote unit with the subset of the plurality of error vectors comprises the step of modifying the location of the remote unit with a plurality of error vectors calculated with calibration units within a first distance from the location of the remote unit, and not calculated with calibration units greater than the first distance from the location of the remote unit.
Claim 13
Dependent Claim
28 words
The method of claim 7 further comprising the step of calculating an uncertainty in the calibrated location estimate based on the subset of the plurality of error vectors.
Claim 14
Dependent Claim
38 words
The method of claim 7 wherein the step of receiving the plurality of independently transmitted first locations of the plurality of calibration units comprises the step of receiving a Global Positioning System (GPS) measurement from the calibration unit.
Claim 15
Independent Claim
67 words
An apparatus comprising: location finding equipment coupled to the database, the location finding equipment having an independently transmitted first location of a mobile unit as an input and outputting an error vector based on the first location of the mobile unit and an estimated location of the mobile unit; and a database having the error vector and the estimated location of the mobile unit as an input.
Claim 16
Independent Claim
67 words
An apparatus comprising: location finding equipment coupled to the database, the location finding equipment having an independently transmitted first location of a mobile unit as an input and outputting an error vector based on the first location of the mobile unit and an estimated location of the mobile unit; and a database having the error vector and the estimated location of the mobile unit as an input.
References Cited (Backward Citations)
US3659085A
Cited
US4833478A
Cited
US4636796A
Cited
US5686902A
Cited
US5490073A
Cited
US5327144A
Cited
US5523763A
Cited
US5508708A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-01-10 | 2003-07-12 | 2004-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-01-10 | 2007-07-12 | 2008-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-01-10 | 2011-07-12 | 2012-01-11 | $7700.00 | Window Closed / Lapsed |