Calibration of GNSS stations for hardware time delay determination.
This Service aims at calibrating GNSS stations for timing applications, i.e. determining the hardware delays in the antenna, cables and receiver. Two methods can be used: absolute or relative. The absolute calibration uses a GNSS signal simulator and a Vector Network Analyzer which compares the simulated signal with the signal measured by the receiving equipment; the uncertainty on the measured delays is at the level of 1 ns. The relative calibration determines the hardware delays of the receiving chain with respect to a reference station already calibrated, with a combined uncertainty lower than 4 ns.
The user will know the hardware delays of its GNSS receiving station, and will hence be able to determine accurately from the GNSS measurements the offset between its local clock and the GNSS time scale.
This service will allow GNSS time transfer with an uncertainty lower than a few nanosecond.