Open AccessGlobal positioning system pseudolite-based relative navigation.
Author(s) -
Eric W. Monda
Publication year - 2004
Language(s) - English
Resource type - Reports
DOI - 10.2172/918766
Subject(s) - global positioning system , kalman filter , computer science , navigation system , real time computing , filter (signal processing) , position (finance) , process (computing) , positioning system , extended kalman filter , remote sensing , telecommunications , engineering , geography , computer vision , artificial intelligence , finance , economics , operating system , structural engineering , node (physics)
Though the Global Positioning System has revolutionized navigation in the modern age, it is limited in its capability for some applications because an unobstructed line of sight to a minimum of four satellites is required. One way of augmenting the system in small areas is by employing pseudolites to broadcast additional signals that can be used to improve the user's position solution. At the Navigation Systems Testing Laboratory (NSTL) at NASA's Johnson Space Center in Houston, TX, research has been underway on the use of pseudolites to perform precision relative navigation. Based on the findings of previous research done at the NSTL, the method used to process the pseudolite measurements is an extended Kalman filter of the double differenced carrier phase measurements. By employing simulations of the system, as well as processing previously collected data in a real time manner, sub-meter tracking of a moving receiver with carrier phase measurements in the extended Kalman filter appears to be possible