Showing papers on "GNSS augmentation published in 1970"
TL;DR: In this paper, a short Doppler computer program which promotes better and more consistent accuracy is described, including documentation of 150 ft. RMS fix results, and Approaches to an integrated navigation system are reviewed.
Abstract: Installation and operation of satellite navigation equipment is described, including what the user should expect during a satellite pass. Characteristics of the new short Doppler computer program which promote better and more consistent accuracy are given, including documentation of 150 ft. RMS fix results. Approaches to an integrated navigation system are reviewed.
5 citations
TL;DR: In this paper, the satellite system operation is subdivided naturally into two parts: satellite orbit determination and navigation by the user, where the satellite is tracked from one or more ground stations and the satellite ephemerides determined along with calibration information on on-board equipment, such as a precision oscillator.
3 citations
30 Jan 1970
TL;DR: In this paper, a hybrid satellite/inertial navigation system with a master ground station (with associated calibration stations) periodically checks and updates the satellite clocks and ephemerides.
Abstract: : A hybrid satellite/inertial navigation system possessing many unique and desirable features is defined. A set of four satellites placed in 24-hour inclined, elliptical orbits can be made so that three satellites form a stationary, circular ground trace with the fourth satellite moving in a smaller, closed path at the center. Three or four such constellations can provide nearly global coverage. The system works on the following principle: Each satellite contains a clock, a transmitter, and a receiver. A master ground station (with associated calibration stations) periodically checks and updates the satellite clocks and ephemerides. The satellites are constantly transmitting a signal modulated with a time code. The user simultaneously receives all four signals, which contain range, time, and satellite position data. With four such measurements the user can both adjust his clock to that of the satellites and compute a three-dimensional fix. Correspondingly, with range rate data, he can establish a three-dimensional velocity. It is important to note that the satellite system described is not self-contained. However, if the user combines this system with an inertial navigation system, many of the advantages of a totally self-contained system can be achieved. The satellite system would be used to position-update, align, and failure-monitor the inertial system and calibrate the accelerometer. (Author)
2 citations