Analysis, Modeling, and Mitigation of Cross-Rate Interference in eLoran

The General Lighthouse Authorities of the UK and Ireland (GLA) have selected eLoran as the most cost-effective way of complementing GNSS to provide resilient positioning, navigation, and timing within their waters. Achieving adequate eLoran coverage over the GLA service area will require a number of new transmitting stations to be installed. Due to the nature of eLoran transmissions, new stations can contribute as sources of interference which is often referred to as Cross-Rate Interference (CRI). This paper investigates the impact of CRI on the positioning accuracy of eLoran and explores mitigation methods. Analytical models of the pseudorange and positioning error due to CRI are presented and validated, and applications to coverage prediction and optimal eLoran Group Repetition Interval (GRI) selection are demonstrated. Results show that the CRI-induced errors can be substantially reduced through the judicious choice of GRIs and the use of state-of-the-art eLoran signal processing techniques. Copyright © 2016 Institute of Navigation