Terrestrially based navigation system incorporating co-located pseudolite transmitters, electronic position-signal receivers and electronic position-signal transmitters for broadcasting position-fixing signals for location and navigation; navigation and positioning equipment, namely, pseudolite transmitters, electronic position-signal receivers and electronic position-signal transmitters; computer hardware configured to control pseudolite transmitters, electronic position-signal receivers and electronic position-signal transmitters; computer software which determines precise positioning from information contained in broadcast position-fixing signals; computerized hardware and operating software used to calculate the geographic location of movable objects including aircraft, marine vessels, land vehicles, human beings, animals, robots, cargo and packages; instruments comprising pseudolite transmitters, electronic position-signal receivers, electronic position-signal transmitters, and computerized hardware and software used to determine position in land and marine surveying, mapping, tracking and navigation, and tracking and navigation of inanimate and animate objects