Civil Satellite Positioning Systems

Enhanced Positioning Performance using GIS-Assisted Satellite Positioning

This paper presents the initial results of research suggesting a concept of taking an advantage of known GIS information, primarily the ground elevation contour, to enhance the performance of satellite positioning systems in terms of improved availability and positioning accuracy. Recent advances of laser telemetry allow nowadays very accurate measurements of the Earth’s elevation down to sub-m...

Stand-Alone Satellite-Based Global Positioning

Instant Active Positioning with One LEO Satellite

Autonomous position determination in the Globalstar satellite communication system is discussed. ( ) The two-way communication between a user terminal on the earth’s surface and a single low earth orbit LEO satellite makes it possible to derive range and range-rate and determine the user terminal position instantly. Expected accuracy is presented, and a simple direct solution is given. INTRODUC...

Receiver Biases in Global Positioning Satellite Ranging

Accurate Positioning in a Flight Inspection System Using Differential Global Navigation Satellite Systems

The purpose of a flight inspection system is to calibrate and evaluate the performance of aircraft navigation and landing aids to ensure conformance to specifications. This mission requires that the flight inspection platform have a reference position estimate significantly more accurate than that of the facility under inspection, i.e., tenths of meter accuracy over a region of many kilometers,...