satellite orbit determination is a method of determining the state vector, i.e., position and velocity, of a low earth orbiting (leo) satellite or interplanetary spacecraft. during the past two decades, many satellites with various applications including geodetic applications have been launched at low altitudes. for instance, topex / poseidon, champ, grace and goce are the examples of the geode...

Traditional Global Navigation Satellite System (GNSS) immunity to interference may be approaching a practical performance ceiling. Greater gains are possible outside traditional GNSS orbits and spectrum. from low Earth orbit (LEO) has long been viewed as promising but expensive, requiring large constellations for rapid navigation solutions. The recent emergence of commercial broadband LEO mega-...

A vision for the future: In 2020, aerospace forces will be a reality. A notional composite aerospace wing, based in the continental United States (CONUS), would include a squadron of rocket-powered transatmospheric vehicles (TAV). These Black Horse vehicles, derived from the Question Mark 2 X-vehicle shown in figure 1 and described later in this paper, will be fighter-sized airframes capable of...

Title of Thesis: APPLICATION OF X-RAY PULSAR NAVIGATION: A CHARACTERIZATION OF THE EARTH ORBIT TRADE SPACE Wayne Hong Yu, Master of Science, 2015 Thesis directed by: Dr. Liam Healy Department of Aerospace Engineering The potential for pulsars as a navigation source has been studied since their discovery in 1967. X-ray pulsar navigation (XNAV) is a celestial navigation system that uses the consi...

Recent technological advances have accelerated a renaissance in usage of non-geostationary (non-GSO) communication satellites in provision of various services domestically and globally. Early ventures into communication satellites have used satellites in low Earth orbits. The main reasons for this mode of operation were that the booster technology was not available to lift satellites into a hig...

The precise orbit determination problem is to accurately determine the position and velocity vectors of an orbiting satellite. In this paper we review the general contents of the orbit determination process, with particular emphasis on Low Earth Orbit (LEO) satellites. The different orbit determination approaches and the different force models contained within are briefly discussed. The two mai...

Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 ...