Enhancing the UTCr algorithm: performance improvements and optimization

Abstract Considering the evolving needs of time metrology and the importance of providing contributing laboratories with more frequent access to a realization of Coordinated Universal Time (UTC) than through the monthly BIPM Circular T, the Time Department introduced a rapid realization of UTC (UTCr), officially published on a weekly basis since July 2013. The algorithm used to compute UTCr was first published in 2014, and since then only minor mathematical adjustments have been applied. In the initial paper, it was stated that UTCr could be maintained within ±2 ns of UTC. An improved UTCr calculation method is proposed in this paper and it has recently been implemented, reducing deviation from UTC to within ±1 ns.