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原文传递 The Commercialization of the Global Positioning System

题名：	The Commercialization of the Global Positioning System
作者：	McLaughlin, Gregory D.;
关键词：	GLOBAL POSITIONING SYSTEM, ACCESS, CIVILIAN POPULATION, GROWTH(GENERAL), NAVIGATION SATELLITES, COMMERCIAL EQUIPMENT, COMMERCIAL COMMUNICATIONS.
摘要：	In April of 1973, a memorandum issued by the Deputy Secretary of Defense consolidated two experimental satellite navigation programs into one effort: The NAVSTAR Global Positioning System was born. After 22 years and $8 billion dollars, the system was finally declared fully operational in 1995. In 1983, a Reagan Administration directive authorized civilian use of the system. Evidence, however, shows that civil access to GPS was intended all along. Since the Reagan decision, the civil market has grown exponentially, and is predicted to exceed $8 billion in the year 2000. By 1995 alone, civil users outnumbered military users by ten to one. while civil access is permitted, its users are subject to an intentionally degraded signal called "selective availability" that restricts accuracy to 100 meters. Civil users resent the degradation policy and have resorted to differential GPS techniques to evade the accuracy restrictions. Some commercial providers claim their subscription services allow accuracies close to 45 centimeters. The Department of Transportation is also in the differential GPS business, providing maritime and aviation augmentations. By Presidential decision, selective availability will be removed within ten years. Examining the Department of Defense's initial vision, the forces behind the granting of commercial access, and the current state of GPS implementation, the study attempts to determine the effects of commercialization on military use of the system. Has GPS provided all the benefits its designers envisioned? Has civil access degraded its military utility, or has it actually enhanced its military role? Considering these issues, it becomes apparent that the growth of GPS has seen tremendous cost reductions and innovation in applications of the technology. Although the growth of civil users has created some difficulties for DoD, civil access has actually enhanced DoD's ability to field the system and procure user equipment.
总页数：	64
报告类型：	科技报告