Performance Trials of an Integrated Loran/GPS/IMU Navigation System. Part 2
Abstract
The 2001 Volpe National Transportation Systems Center report on GPS vulnerabilities identified Loran-C as one possible backup system for GPS. The Federal Aviation Administration (FAA) observed in its recently completed Navigation and Landing Transition Study that Loran-C, as an independent radio navigation system, is theoretically the best backup for GPS; however, this study also observed that Loran-C's potential benefits hinge upon the level of position accuracy actually realized (as measured by the 2 drms error radius). For aviation applications this is the ability to support non-precision approach (NPA) at a Required Navigation Performance (RNP) of 0.3 which equates to a 2 drms error of 309 meters and for marine applications this is the ability to support Harbor Entrance and Approach (HEA) with 8-20 m of accuracy. The recently released report of the DOT Radionavigation Task Force recommended to "complete the evaluation of enhanced Loran to validate the expectation that it will provide the performance to support aviation NPA and maritime HEA operations." To meet this need, the FAA is currently leading a team consisting of members from industry, government, and academia to provide guidance to the policy makers in their evaluation of the future of enhanced Loran (eLoran) in the United States. Through FAA sponsoring, the U.S. Coast Guard Academy (USCGA) is responsible for conducting some of the tests and evaluations to help determine whether eLoran can provide the accuracy, availability, integrity, and continuity to meet these requirements. The key to meeting HEA accuracy requirements is an accurate ASF spatial grid. This can be met by a very dense grid of ASF values; however, this increases the problems with grid distribution and storage on the receiver. Previous work (ION AM June 2004) suggested that a sparse grid can be used and accuracy targets still reach
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2006
- Accession Number
- ADA573636
Entities
People
- Christian Oates
- Gregory Johnson
- Hunter Atherton
- Michael Teixeira
- Peter Swaszek
- Richard Hartnett
- Ruslan Shalaev
Organizations
- United States Coast Guard Academy