Title :
Observability, ensemble averaging and GPS time
Author :
Chaffee, James W.
Author_Institution :
Sci. Applications Int. Corp., San Diego, CA, USA
fDate :
1/1/1992 12:00:00 AM
Abstract :
Obtaining time from an ensemble of clocks with a Kalman filter when the system is not observable is examined. Particular attention is given to the Global Positioning System (GPS) master control station (MCS) Kalman filter and the ramifications of estimating ensemble time under conditions of unobservability are explored. The effect of one proposed workaround to problems caused by unobservability is addressed
Keywords :
Kalman filters; clocks; observability; radionavigation; satellite relay systems; signal processing; time measurement; GPS time; Global Positioning System; Kalman filter; ensemble averaging; ensemble time; master clock; master control station; observability; unobservability; Algorithm design and analysis; Clocks; Control systems; Covariance matrix; Differential equations; Global Positioning System; Laplace equations; Observability; State estimation; Transfer functions;
Journal_Title :
Aerospace and Electronic Systems, IEEE Transactions on
