Ionospheric and Plasmaspheric Effects in Satellite Navigation Systems,

摘要

A space-based radio navigation system could provide military and civilian users with precise three-dimensional position and velocity data. The navigation signals would contain data such as satellite identity,real-time ephemerides information,system time,and other needed information. To determine his position and velocity,the user will cross-correlate the coded time signal received from the satellite with the same coded time signal generated in his receiver. The phase difference,or equivalently the time displacement,between the phase at the user's receiver and the incoming phase,determines the range to the satellite. Simultaneous measurement of such relative phases from four different satellites will permit the user to determine his range and his clock bias with respect to the satellite's position and clock,respectively.