The Institute operates three different laboratories in which, among other things, investigations are carried out into time synchronisation, the generation of a system time from several clocks (ensemble time), the verification of system time algorithms (composite clock) with real measurement data or time transfer. The laboratory rooms are individually air-conditioned and protected against power failure by an uninterruptible power supply and a battery feed.
High-precision atomic clocks (two active hydrogen masers, one passive hydrogen maser and three caesium clocks) based on transitions of the hyperfine structure are operated in the clock laboratory. The separate room ensures that the sensitive clocks are not affected by external influences. One of these caesium clocks, in combination with a calibrated GNSS time receiver, represents UTC(DLR) and thus realises the connection to world time.
The signals from these atomic clocks are fed into the time laboratory and distributed to various measuring systems there. Here, in addition to the above-mentioned investigations and realisations, comparative measurements with clocks not belonging to the laboratory as well as signal investigations with the help of GNSS time receivers can be carried out.
Furthermore, the Institute operates a laboratory designed for the operation of optical clocks. This applies in particular to the installation site and the measuring equipment in order to measure optical clocks provided by the Institute of Space Systems (for example, RY) against each other or to compare them with the Institute's own atomic clocks from the clock laboratory in order to be able to evaluate their stability with regard to long-term behaviour.
Image: Enno Kapitza for DLR