GPS precise positioning techniques for remote marine applications

Marine geodesy, offshore surveys and physical oceanography are usually related to the highly precise kinematic positioning of surveying platforms such as vessels, buoys and aircrafts. Currently, the Global Navigation Satellite Systems (GNSS) can provide a kinematic positioning accuracy of decimeter to centimeter level in relative mode, being potentially an appropriate choice for determining marine platform positions. However, these positioning techniques are related to the presence of reference stations and are not applicable in remote areas. In this work, two approaches are considered to determine the altitude variations of GPS antenna, which is an important parameter for the analysis of a ship motion. In detail, time-differencing of carrier phase measurements and precise point positioning approaches are applied on static data, collected by a single-frequency receiver, in order to assess the vertical variations performance.