Robust Time Scale Design and Implementation for Telescope Time in a Remote Desert Environment

Abstract

A clock ensemble for tracking time for a next generation radio telescope (MeerKAT) is being built, to be able provide robust timing w.r.t. UTC over long periods (~10 years) in a remote desert environment at the phase center of the MeerKAT-the master clock timing edge as supplied to the telescope is called the KTT (Karoo Telescope Time). This system consists out of two masers, two GPS/Rb clocks, a high stability crystal, and two time transfer systems to link with the National Metrology Institute of South Africa (NMISA), and hardware based clock selection devices to enable signal routing of the master clock pulse per second and 10MHz frequency reference to the telescope. The system is designed for high availability by making use of redundant climate control, multiple power backup and redundant software logging. Data on the initial time tracking capabilities are presented. Low phase noise and drift of the system for supplying synthesizers has been achieved via vibration isolation, and temperature stabilization in purpose built infrastructure as is shown in data. The system timing is calculated post facto (as opposed to real time realization) due to the lowest timing uncertainty needed on pulsar timing data especially for gravitational wave work. The system architecture and initial measurement on the system is presented.