For Want of a Nail: An Assessment of Global Positioning System Satellite Replenishment

Abstract

Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. The original document contains color images. ABSTRACTDespite its vital importance to the welfare and security of the nation, the Global Positioning System (GPS) constellation is populated with numerous satellites operating well beyond their design life. These aging satellites are more likely to malfunction, which can reduce service coverage, degrade accuracy, and in some cases, transmit dangerously inaccurate data. The Air Force currently subscribes to a launch to sustain (LTS) GPS satellite replenishment strategy. Under this strategy, new satellites are launched only after a satellite failure or just prior to a failure. The purpose of this monograph is to investigate whether the Air Force should forgo its LTS replenishment strategy in favor of a more aggressive launch to augment (LTA) strategy in order to proactively replace high-risk satellites and to accelerate modernization timelines. It will be shown that the explosive growth of GPS over the past fifteen years has outpaced the Air Force's strategy on satellite replenishment. The growing importance of GPS must be matched with a progressive replenishment strategy that sustains its reliability and improves its utility for military, civil, and commercial users. The LTS strategy has placed a disproportionate emphasis on operational efficiency at the expense of operational effectiveness and has impaired the timely insertion of critical new capabilities into the constellation. A LTA strategy would help to reverse this trend. The Global Positioning System (GPS) has become a vital component to both the military and civilian infrastructures. U.S. military forces have evolved from using its signal for routine navigation to depending on it for nearly every facet of combat operations. GPS is also seamlessly integrated into every major civil infrastructure, including transportation, communications, energy, commerce, banking, and emergency response services. In addition, the accuracy and worldwide availability of GPS has spawned a multi-billion dollar international market representing billions of dollars in annual tax revenue.Despite its vital importance, the GPS constellation is populated with numerous satellites operating well beyond their design life. These agin...

Analysis of GNSS Interference Impact on Society and Evaluation of Spectrum Protection Strategies

“…Every year, the whole market of GNSS products and services increases at an annual rate of about 25% [1]. Some previsions expect that in 2020 [2] more than 1 billion of satellite navigation units will be operatetc.…”