Patent · US Expired

Method of correcting navigation system errors caused by drift

US4817001A · kind A · utility

3Cited by
6References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 17, 1987
Grant dateMar 28, 1989
Priority date
Expiry dateApr 17, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S13/87
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a two way ranging system of the type employing pseudonoise spread spectrum codes there is provided a method for correcting the navigational system of one of two moving stations in space to compensate for relative drift. The point positions of the two stations are calculated by the on-board navigation systems of the individual stations at a first and subsequently at a second position after relative movement. The range from station 1 to station 2 is calculated employing the highly accurate pseudonoise communications ranging systems. The range uncertainty of the range calculation and the trigonmetric relation of the two calculated ranges and the include angle between the line of sight of the range directions is employed to calculate a range of uncertainty parallelogram more accurate that the navigation systems. When a station's point position is indicated by its navigation system to be outside the parallelogram, the navigation system is corrected to compensate for relative drift.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.