ELoran

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Enhanced LORAN (commonly known as eLoran; also known as eLORAN, E-LORAN, or e-LORAN) is a long-range radio navigation system that uses terrestrial towers and the hyperbolic navigation technique. It is an advancement in receiver design and transmission characteristics which increase the accuracy and usefulness of traditional LORAN and LORAN-C.

Interest has been renewed by the potential vulnerability of global navigation satellite systems, [1] and their own propagation and reception limitations. [1] With reported accuracy as good as ± 8 meters, [2] the system becomes competitive with unenhanced GPS. eLoran also includes additional pulses which can transmit auxiliary data such as Differential GPS (DGPS) corrections, as well ensure data integrity against spoofing. [3] [4]

eLoran receivers use "all in view" reception, incorporating signals from all stations in range, not solely those from a single GRI, incorporating time signals and other data from up to forty stations. These enhancements in LORAN make it adequate as a substitute for scenarios where GPS is unavailable or degraded. [5]

In 2017 it was reported by the United States Maritime Association that the United States Coast Guard had reported several episodes of GPS interference in the Black Sea. [6] [7] South Korea has claimed that North Korea has jammed GPS near the border, interfering with airplanes and ships. By 2018, the United States planned to build a new eLoran system as a complement to and backup for the GPS system. The South Korean government has pushed plans to have three eLoran beacons active by 2019, which would be enough to provide accurate corrections for all shipments in the region if North Korea (or anyone else) tries to block GPS again. [8] [9] [10] As of November 2021, no eLoran system has deployed. [11]

Related Research Articles

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References

  1. 1 2 Palmer, Jason (23 February 2010). "Sat-nav systems under growing threat from 'jammers'". BBC News.
  2. ↑ "GPS Backup: Is eLoran the answer?". Aviation Today. April 2012. Archived from the original on 26 June 2012. Retrieved 10 January 2013.
  3. ↑ Lo, Sherman; Peterson, Benjamin (3 August 2016). "Enhanced Loran" (PDF).
  4. ↑ Becker, Georg T.; Lo, Sherman; De Lorenzo, David; Qiu, Di; Paar1, Christof; Enge, Per. "Efficient authentication mechanisms for navigation systems – a radio-navigation case study" (PDF). Archived from the original (PDF) on 29 November 2019. Retrieved 11 March 2019.{{cite web}}: CS1 maint: numeric names: authors list (link)
  5. ↑ Press office (7 February 2008). "Statement from DHS press secretary Laura Keehhner on the adoption of national backup system to GPS" (PDF). press release. United States Department of Homeland Security. Archived from the original (PDF) on 14 May 2008. Retrieved 10 January 2013.
  6. ↑ U.S. Maritime Association. "2017-005A-Black Sea-GPS Interference".
  7. ↑ U.S. Maritime Association. "2017-007-Global-GPS Disruption".
  8. ↑ Gallagher, Sean (7 August 2017). "Radio navigation set to make global return as GPS backup, because cyber". Ars Technica.
  9. ↑ "GPS.gov: LORAN-C Infrastructure & E-LORAN". www.gps.gov.
  10. ↑ Narins, Mitch (2014-06-03). "The Global Loran / eLoran Infrastructure Evolution: A Robust and Resilient PNT Backup for GNSS" (PDF). GPS.gov. Federal Aviation Administration. Retrieved 2022-11-13.
  11. ↑ "ELoran: Part of the solution to GNSS vulnerability". 3 November 2021.
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