Advanced instrument landing system

A system for guiding a vehicle along a path utilizing a plurality of satellites each of which transmits signals representing the position of the satellite and precise time in a common time reference comprising:

• first means for receiving said position and precision timing signals to provide a first clock signal in said common time reference;
• means responsive to said first clock signal for transmitting within a time period associated with said transmitting means guidance signals with respect to said guidance path to direct a vehicle along a path and a reference signal, said reference signal being transmitted at a precise time with respect to said first clock signal and within said time period;
• second means disposed in said vehicle for receiving said position and precision timing signals to provide a second clock signal in said common time reference, said second clock signal being in synchronization with said first clock signal;
• means disposed in said vehicle for receiving said guidance and reference signals;
• and
• means coupled to said guidance and reference signal receiving means and to said second means for processing guidance signals received only in said time period associated with said guidance station to guide said vehicle along said path, said processing means including:
• means for determining the time of receipt of said reference signal in said common time reference;
• and
• one way range determining means for determining the range of said vehicle from said transmitting means based upon the difference between said precise time at which said reference signal is transmitted and said time of receipt of said reference signal.

A system for guiding a vehicle utilizing a plurality of satellites each of which transmits signals representing the position of the satellite and precise time in a common time reference, comprising:

• first means for receiving said position and precision timing signals to provide a first clock signal in said common time reference;
• means responsive to said first clock signal for transmitting a range signal at a precise time with respect to said first clock signal and within a time period associated with said transmitting means;
• second means disposed in said vehicle for receiving said position and precision timing signals to provide a second clock signal in said common time reference, said second clock signal being in synchronization with said first clock signal;
• means disposed in said vehicle for receiving said range signal;
• and
• one way range means coupled to said range signal receiving means and to said second means for processing a range signal received within said time period to determine range from the difference between said precise time of transmission and the time of receipt of said range signal.