摘要
To degrade location accuracy for unauthorized GPS users, US government applied Selective Availability (SA) to Global Positioning System (GPS). In this paper we discuss an anti-SAapproach to improve location accuracy which is very important in landing position, and then we derived the SA error by eliminating almost all other errors including ionospheric and tropospheric timedelays and clock errors both in satellites and in receiver, etc. By means of the system identificationtheory, an SA errorl all SA error model with the second-order Gauss-Maukov stochastic process wasderived and simulated. With the selected parameters of the stochastic process) the simulation resultsshow that there is the excellent agreement between the simulated SA error model and that of reallyapplied in GPS system.
To degrade location accuracy for unauthorized GPS users, US government applied Selective Availability (SA) to Global Positioning System (GPS). In this paper we discuss an anti-SAapproach to improve location accuracy which is very important in landing position, and then we derived the SA error by eliminating almost all other errors including ionospheric and tropospheric timedelays and clock errors both in satellites and in receiver, etc. By means of the system identificationtheory, an SA errorl all SA error model with the second-order Gauss-Maukov stochastic process wasderived and simulated. With the selected parameters of the stochastic process) the simulation resultsshow that there is the excellent agreement between the simulated SA error model and that of reallyapplied in GPS system.
