GPS-based Interferometric Heading Determination Using Carrier Phase Measurement

Abstract

This paper presents a determination of a heading angle using carrier phase differential GPS (CPDGPS) measurement between two slave antennas. Heading of a platform can be obtained from measurements with two linearly independent interferometers where each interferometer involves of two separate antennas or baseline length. In this particular test, Such antennas are separated by a small length to remove the corresponding errors formed by the GPS system, such technique of removing particular errors are named as Single Difference(SD) and Double Difference(DD)Measurements. Measuring phase difference between antennas is a quite complex method in GPS because of the full number of carrier cycles are unknown or it is ambiguous in nature known as integer ambiguity problem. To remove the integer ambiguity problem we processed the LAMBDA (Least Square Ambiguity Decorrelation Adjustment) to obtain a higher heading accuracy for static experiments. Furthermore, the relative position of a rover receiver is also mentioned in the paper within a centimeter level of accuracy.