GPS World, January 2014
EXPERT ADVICE Experts have demonstrated the folly of relying upon one electronic navigation system and how things can go horribly wrong The Way Forward Fortunately awareness and understanding of the problem within government and the general public has continued to grow The U S National Space Based Positioning Navigation and Timing PNT Advisory Board published a seminal white paper in 2010 on the topic strongly recommending the establishment of an eLoran system Todd Humphreys the UK navigation authority and others have provided numerous graphic demonstrations of the folly of relying upon just one electronic navigation system and how things can go horribly wrong Some of these have been well publicized Other incidents are known only to a few There are also signs that the U S intelligence cyber and defense communities are becoming more and more concerned North Koreas repeated jamming of satellite navigation and timing signals has delivered a particularly powerful lesson South Korea has reacted by committing to establishment of a robust eLoran system The UK has established an eLoran system and is expanding it Russia and China have retained their versions of Loran C and are using it to augment satellite services Russia has announced it will upgrade its system to eLoran in cooperation with the UK and China may not be far behind Saudi Arabia is upgrading its system to eLoran and India has plans for an eLoran network in the near future In December Iran announced it has established a land based system with powerful transmitters that is completely different with GPS Allies adversaries and economic competitors are augmenting satellite services with strong terrestrial ones The United States will soon be one of only a small number of major economies that does not have a strong difficult to disrupt terrestrial system protecting its critical infrastructure and providing value added utilities DODs chief information officer expressed interest in eLoran as part of DODs pivot to the Pacific But providing a system at home is not in Defenses job description nor should it be Respected leaders at the Departments of Transportation and Homeland Security still see this as an important issue that needs to be addressed The question for them now is not one of technology The technology decision made in 2008 has since been revalidated by a plethora of academic papers risk estimates and white papers eLoran still appears to be the most effective and least expensive solution available DOT and DHS must resolve questions of governance and how to fund the system in one of the most difficult federal budgetary climates in decades How The answer could lie in a publicprivate partnership P3 In such an arrangement the government would bring its interests and the infrastructure it owns to the table An entity in the non profit sector or industry would provide investment to refurbish the infrastructure stand up and operate the system Such a P3 enterprise could not only pay for itself but be an ongoing source of revenue for both the government and the private entity The Business Model Demand A well configured eLoran system can provide navigation accuracy to within 8 to 10 meters and timing accuracy to within 30 nanoseconds This meets the needs of an estimated 95 percent of users in the United States While eLoran does not offer the sub meter precision of a high end augmented GPS GNSS system it has its own advantages In addition to being very difficult to disrupt its high power typically 400 kW transmitters low frequency 100 kHz signal easily penetrates and is usable underground inside buildings and underwater where satellite and cell phone signals on much higher frequencies cannot reach The UK experience with eLoran and private surveys in the United States have shown high commercial demand for a ubiquitous wireless precise and resilient time and navigation service Power companies want to synchronize grids with a signal that cant be disrupted by a delivery driver trying to avoid being tracked by his boss Cell phone companies would be happy to have alternative timing capability in their networks provided through inexpensive eLoran receivers Operators of autonomous vehicles want a robust navigation signal and guaranteed communications And it would be welcomed by the many users who research shows rely upon GPS GNSS time for mission critical applications and who have no secondary source on which to fall back in the event of a disruption Since eLoran easily penetrates inside buildings underground and underwater it can be used for timing and navigation in many places where no other navigation and timing sources are available For example it has been used for underground and underwater navigation When paired with an accurate satellite signal before going underground or submerging eLoran could enable a navigation receiver to maintain a comparable level of precision for several hours Even after that it would provide the navigator an accurate underground underwater compass and a good position The eLoran navigation and timing system now in operation in the United Kingdom also generates revenue by transmitting data While the full potential of this third party data channel capability is still being explored the ability to assure data delivery to and communicate with such areas is GPS World January 2014 www gpsworld com 12
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