California Partners for Advanced Transportation Technology

This report contains research results of studies on magnetic marker systems that are used as a posi-tionreference system for Advanced Vehicle Control and Safety Systems. Effects of external objectsand earth background fields on such systems are investigated with experimental measurements inPart I. The results show that signal processing techniques must be adopted in field applications toimprove the accuracy and robustness of sensing algorithms. Part II of the report contains experimen-talresults from an evaluation study of PATH marker system and 3M Tape system. The objective isto identify the characteristics of these two sensing systems and to offer a comparison of their distinctfeatures. It was found that PATH marker systems offer a stronger signal-to-noise ratio and providesa more accurate position measurement.