United States Military Begins to Recognize the Susceptibility of the GlobalPositioning System to Jamming

摘要

In mid-1993, the United States Department of Defense directed the Defense ScienceBoard (DSB) to establish a task force specifically devoted to the study of the susceptibility of the Global Positioning System (GPS) to jamming and methods of countering jamming. Its purposes were to solve problems having to do with the survivability of GPS when encountering enemy jamming and to fmd ways to improve its antijamming capabilities. GPS repeatedly performed outstanding service in the Persian Gulf War. American military vehicles, ships, and airplanes were all fitted with GPS equipment, and portable receivers played complementary roles. In addition, many GPS receivers were fitted to the guidance and control equipment in tactical missiles and precision-guided ammunition. This situation caused the Pentagon to worry that, in future wars, if the enemy takes effective electronic countermeasures, an overreliance on GPS will bring about results that are just the opposite of what was desired. In view of this consideration, the office of the Assistant Secretary of Defense demanded that the task force established by the DSB put forward an optimal technological plan to improve the antijamming capabilities of GPS and especially emphasized that this improvement should be applied to GPS in tactical weapon systems.