EP2575271B1

Position Estimation Using a Network of Global-Positioning Receivers

Abstract

This record has no abstract on file.

EP2575271B1, drawing sheet 1
Sheet 1 of 356

Term

Term ended

Expired 23 September 2023, 3 years ago.

  1. Priority
  2. Filed
  3. Granted
  4. Expired
  5. Today

17 claims: 3 independent, 14 dependent

  1. 1
    A method of estimating the location of a rover station (R) with the use of a first base station (B1), a second base station (B2), and a third base station (B3), the method comprising:a) (202) receiving locations of the first base station, the second base station, and the third base station;b) (206) receiving measured satellite navigation data as received by the rover station, the first base staton, the second base station, and the third base station;c) obtaining a first set of satellite-phase cycle ambiguities related to the baseline between the first and second base stations, and a second set of satellite-phase cycle ambiguities related to the baseline between the first and third base stations;d) (208) obtaining a first time offset representative of a first difference between a first offset from true GPS time of the clock of the first base station and a second offset from true GPS time of the clock of the second base station;e) (208) obtaining a second time offset representative of a second difference between the first offset from true GPS time of the clock of the first base station and a third offset from true GPS time of the clock of the third base station;f) (214) generating a first set of residuals of differential navigation equations for a first baseline (R-B1) between the rover station and the first base station, the residuals being related to at least the measured satellite data received by the rover station and the first base station, the locations of the satellites, and the locations of the rover station and the first base station;g) (214) generating a second set of residuals of differential navigation equations for a second baseline (R-B2) between the rover station and the second base station, the residuals being related to at least the measured satellite data received by the rover station and the second base station, the locations of the satellites, and the locations of the rover station and the second base station;h) generating a modified second set of residuals by substituting, within the second set of residuals, a first unknown time offset associated with the second baseline (R-B2) with a value composed of a sum of the first time offset and a time offset associated with the first baseline (R-B1);i) (214) generating a third set of residuals of differential navigation equations for a third baseline (R-B3) between the rover station and the third base station, the residuals being related to at least the measured satellite data received by the rover station and the third base station, the locations of the satellites, and the locations of the rover station and the third base station;j) generating a modified third set of residuals by substituting, within the third set of residuals, a second unknown time offset associated with the third baseline (R-B3) with a value composed of a sum of the second time offset and the time offset associated with the first baseline (R-B1);and k) (218) generating an estimate of the rover station's location from the first set of residuals, the modified second set of residuals, the modified third set of residuals, the first time offset, the first set of satellite-phase cycle ambiguities, the second time offset, and second set of satellite-phase cycle ambiguities.
  2. 7
    A computer program product for directing a computer processor to estimate the location of a rover station (R) with the use of a first base station (B1) and a second base station (B2), locations of the first base station and the second base station, and measured satellite data as received by the rover station, the first base station, and the second base station, the computer program product comprising:a computer-readable medium;an initial set of instructions embodied on the computer-readable medium which directs the data processor to receive the locations of the first base station, and the second base station;a first set of instructions embodied on the computer-readable medium which directs the data processor to obtain a first time offset representative of difference between a first offset from true GPS time of the clock of the first base station and a second offset from true GPS time of the clock of the second base station;a second set of instructions embodied on the computer-readable medium which directs the data processor to generate a first set of residuals of differential navigation equations associated with a first baseline (R-B1) between the rover station and the first base station, the residuals being related to the measured pseudo-range satellite data received by the rover station and the first base station, the locations of the satellites, and the locations of the rover station and the first base station;a third set of instructions embodied on the computer-readable medium which directs the data processor to generate a second set of residuals of differential navigation equations associated with a second baseline (R-B2) between the rover station and the second base station, the residuals being related to the measured pseudo-range satellite data received by the rover station and the second base station, the locations of the satellites, and the locations of the rover station and the second base station;and a fourth set of instructions embodied on the computer-readable medium which directs the data processing system to generate a modified second set of residuals by substituting, within the second set of residuals, a first unknown time offset associated with the second baseline (R-B2) with a value composed of a sum of the first time offset and a time offset associated with the first baseline (R-B1);and a fifth set of instructions embodied on the computer-readable medium which directs the data processing system to generate an estimate of the rover station's location from the first set of residuals, the modified second set of residuals, and the first time offset.
  3. 12
    A computer program product for directing a computer processor to estimate the location of a rover station (R) with the use of a first base station (B1), a second base station (B2), a third base station (B3), locations of the base stations, and measured satellite data as received by the rover station and the base stations, the computer program product comprising:a computer-readable medium;an initial set of instructions embodied on the computer-readable medium which directs the data processor to receive the locations of the first base station, the second base station, and the third base station;a first set of instructions embodied on the computer-readable medium which directs the data processor to obtain a first time offset representative of a first difference between a first offset from true GPS time of the clock of the first base station and a second offset from true GPS time of the clock of the second base station;a second set of instructions embodied on the computer-readable medium which directs the data processor to obtain a second time offset representative of a second difference between the first offset from true GPS time of the clock of the first base station and a third offset from true GPS time of the clock of the third base station;a third set of instructions embodied on the computer-readable medium which directs the data processor to generate a first set of residuals of differential navigation equations associated with a first baseline (R-B1) between the rover station and the first base station, the residuals being related to the measured pseudo-range satellite data received by the rover station and the first base station, the locations of the satellites, and the locations of the rover station and the first base station;a fourth set of instructions embodied on the computer-readable medium which directs the data processor to generate a second set of residuals of differential navigation equations associated with a second baseline (R-B2) between the rover station and the second base station, the residuals being related to the measured pseudo-range satellite data received by the rover station and the second base station, the locations of the satellites, and the locations of the rover station and the second base station;a fifth set of instructions embodied on the computer-readabl medium which directs the data processing system to generate a modified second set of residuals by substituting, within the second set of residuals, a first unknown time offset associated with the second baseline (R-B2) with a value composed of a sum of the first time offset and a time offset associated with the first baseline (R-B1);a sixth set of instructions embodied on the computer-readable medium which directs the data processing system to generate a third set of residuals of differential navigation equations associated with a third baseline (R-B3) between the rover and the third base station, the residuals being related to the measured pseudo-range satellite data received by the rover station and the third base station, the locations of the satellites, and the locations of the rover station and the third base station;a seventh set of instructions embodied on the computer-readable medium which directs the data processing system to generate a modified third set of residuals by substituting, within the third set of residuals, a second unknown time offset associated with the third baseline (R-B3) with a value composed of a sum of the second time offset and the time offset associated with the first baseline (R-B1);and an eighth set of instructions embodied on the computer-readable medium which directs the data processing system to generate an estimate of the rover station's location from the first set of residuals, the modified second set of residuals, the modified third set of residuals, the time offset between the clocks of the first and second base stations, and, the time offset between the clocks of the second and third base stations.