ABSTRACT
The origins of the GPS can be traced back to the early seventies, when research for an U.S. defence navigation satellite system led to the development of the Navstar Global Positioning System.1 Conceived by the U.S. Department of Defence (DOD) to enable positioning of military equipment, including land vehicles, ships, aircraft and precision-guided weapons anywhere in the world, providing global coverage with a ten-metre accuracy,2 the GPS was deployed over two decades at a cost of U.S. $ 10 billion. Having proven to have excellent capabilities in its defence role, it has been integrated into virtually every facet of U.S. and allied military operations,3 which are increasingly reliant on its signals for a variety of purposes, from navigation to modern precision-guided weapons and munitions.4
