An Optimized FIR Predictor for Incomplete Measurement Data of Hydrogen Masers Relative to an Optical Clock

By considering the observation samples of a hydrogen maser relative to an optical clock with time-varying variances, this paper proposes an optimized predictor based on the finite impulse response (FIR) to improve the predictability of hydrogen masers. The design idea and rationality of the predictor were characterized from a theoretical viewpoint, showing its potential predictability for missing partial measurement data or unequal interval measurement data. The prediction results for simulated hydrogen masers reveal its comparable predictability with least squares method (LS). As proof of concept, it was applied to the actual data of typical hydrogen maser relative to a ⁸⁷ Sr optical lattice clock developed by the National Institute of Metrology (NIM). Compared with the LS, the prediction error after 7 days obtained by the proposed method is ~40 ps smaller than LS.