Navigational Satellites are satellites that helps in navigating an areas, known or unknown areas can be access through navigational Satellites.
This satellites are often used by ships and Planes.
The most popular navigational satellites are Global positioning system (GPS), and Navigation Signal Timing and Ranging (NAVSTAR).
GPS was build by United State of America department with the purpose of determining the exact location of the receiver.
Here are the probability of Receiver Location.
In a ship at sea.
In an airplane
In another spacecraft
In your pocket
In an automobile.