eLoran Service Volume Coverage Prediction

Abstract

This thesis answers the following research questions:1. Given the current transmitter configuration,what is the accuracy,availability,and continuity performance of the coverage network in theGeneral Lighthouse Authorities of United Kingdom and Ireland’s geographicalarea if differential eLoran is only applicable at harbour andport locations?2. What is the best method of placing the reference stations in the coveragearea given the constraints?The previous work done by other researchers has been extended to includean improved accuracy model that accounts for the variation of signal delaysdue to conductivity changes along the path from the transmitter to theuser and weather changes experienced at the user’s location. Availabilityand continuity models have been derived using historical transmitter offairdata obtained from Loran control centre located in Brest, France. Ananalytical model that accounts for additional secondary factor delay over aflat terrain has been modelled and included in the coverage tool. A modelwhich determines the optimization of the separation distance between anytwo given reference stations has been developed herein. All these techniqueshave been built into the GLAs coverage software tool thereby extending thesoftware tool’s capability to evaluate accuracy, availability and continuityat any location in the GLAs coverage area. Accuracy, availability and continuityare part of the four eLoran system performance parameters. Theother performance parameter called integrity is discussed but not modelledin this thesis. The developed coverage software tool enables administratorsoverseeing the movement of ships into harbours and in coastal waters toensure that system performance requirements of accuracy, availability andcontinuity are met within the chosen geographical area. Administrators canselect transmitters to be used to predict coverage, identify and plan wherenew transmitters and reference stations need to be installed to meet international standards for accuracy, availability and continuity, giving a safe and reliable service. The developed coverage tool’s outputs serve as a guide toadministrators as to whether resources such as reference stations are optimizedor not.

Date of Award	3 Jul 2018
Original language	English
Awarding Institution	University of Bath
Supervisor	Ivan Astin (Supervisor) & Nathan Smith (Supervisor)