A Kalman filter UTC(k) prediction and steering algorithm

A clock prediction and steering algorithm has been developed to produce a UTC(k) timescale that may be maintained close to UTC. The algorithm is based on predicting individual (UTC — C I ) clock offsets which are then combined to form a physical UTC(k) timescale. The algorithm is designed to use data from all the available laboratory clocks without the use of a clock ensemble algorithm. The performance of the underlying Kalman filter predictor is examined in depth, along with initial results using three years of historical NPL clock and UTC data combined with a simulated steering process.