Precise time transfer using GPS carrier phase-based techniques

We have used the carrier phase signal from the satellites in the Global Positioning System (GPS) in an attempt to perform precise time and frequency transfer. The method is commonly used in the geodetic community to obtain mm-level precision over global distances. When estimating the station position other parameters must be solved for. Such parameters include, e.g., the atmospheric propagation delay as well as determination of clocks in the GPS-receivers. In this study we have focused on the evaluation of these clock solutions for two Swedish GPS stations with particular interest for the timing community. One station is collocated with the Swedish national laboratory for time and frequency and equipped with several cesium frequency standards. The other station is located at the Onsala Space Observatory where all receivers are connected to a hydrogen maser