Enhanced LORAN (commonly known as eLoran; also known as eLORAN, E-LORAN, or e-LORAN) is a long-range

radio navigation Radio navigation or radionavigation is the application of radio waves to geolocalization, determine a position of an object on the Earth, either the vessel or an obstruction. Like radiolocation, it is a type of Radiodetermination-satellite servi ...

system that uses terrestrial towers and the

hyperbolic navigation Hyperbolic navigation is a class of radio navigation systems in which a navigation receiver instrument is used to determine location based on the difference in timing of radio waves received from radio navigation beacon transmitters. Such syste ...

technique. It is an advancement in receiver design and transmission characteristics which increase the accuracy and usefulness of traditional

LORAN LORAN (Long Range Navigation) was a hyperbolic navigation, hyperbolic radio navigation system developed in the United States during World War II. It was similar to the UK's Gee (navigation), Gee system but operated at lower frequencies in order ...

and LORAN-C. Interest has been renewed by the potential vulnerability of

global navigation satellite system A satellite navigation or satnav system is a system that uses satellites to provide autonomous geopositioning. A satellite navigation system with global coverage is termed global navigation satellite system (GNSS). , four global systems are op ...

s, and their own propagation and reception limitations. With reported accuracy as good as ± 8 meters, the system becomes competitive with unenhanced GPS. eLoran also includes additional pulses which can transmit auxiliary data such as

Differential GPS Differential Global Positioning Systems (DGPSs) supplement and enhance the positional data available from global navigation satellite systems (GNSSs). A DGPS can increase accuracy of positional data by about a thousandfold, from approximately to ...

(DGPS) corrections, as well as ensure

data integrity Data integrity is the maintenance of, and the assurance of, data accuracy and consistency over its entire Information Lifecycle Management, life-cycle. It is a critical aspect to the design, implementation, and usage of any system that stores, proc ...

against spoofing. eLoran receivers use "all in view" reception, incorporating signals from all stations in range, not solely those from a single Group Repetition Interval (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. 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 The Black Sea is a marginal sea, marginal Mediterranean sea (oceanography), mediterranean sea lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bound ...

. 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. As of November 2021, no eLoran system has deployed.

References

{{Reflist Navigational aids Aeronautical navigation systems

See also

References