GNSS time and frequency transfers through national positioning, navigation and timing infrastructure

GNSS signals have been a practical time transfer tool to realise a Coordinated Universal Time (UTC) and set civilian clocks around the world with respect to this atomic time standard. UTC time scale is maintained by the International Bureau of Weights and Measurements (BIPM) adjusted to be close to a time scale based on the Earth’s rotation. In Thailand, the official atomic time clocks are maintained by the National Institute of Metrology Thailand (NIMT) to produce UTC(NIMT) and Thailand standard time which is always 7 hours ahead of UTC(NIMT) because of the time zone differences between Greenwich and Bangkok. National Positioning, Navigation and Timing (PNT) infrastructure comprises of GNSS geodetic receivers uniformly distributed to continually observe GNSS signals, mainly for geodetic survey applications both real-time and post-processing services. NIMT is involved in order to provide time link to UTC and to determine the characteristics of GNSS receiver internal clocks; namely, fractional frequency offset and frequency stabilities by applying the GNSS time transfer techniques of common-view algorithms. Monitored time differences with respect to UTC(NIMT) are achieved from selected 4 ground stations in different parts of the country with observations of 21 days in order to determine the frequency stability at 1-day and 7-day modes. GNSS standard log files; in RINEX format, at these receivers are transformed into a time transfer standard format; CGGTTS, used to compute the time differences between two stations, the fractional frequency offset and the frequency stability. Averaged fractional frequency offsets are 2.8 × 10 − 13 Hertz/Hertz 2.8\times {10^{-13}}\hspace{2.38387pt}\text{Hertz/Hertz} and computed Allan deviation is around 1.5 × 10 − 13 Hertz/Hertz 1.5\times {10^{-13}}\hspace{2.38387pt}\text{Hertz/Hertz} for an averaging time of 1 day. The comparison of the national time scale and receiver clock offsets of every receivers in this national GNSS PNT infrastructure could be accomplished through common-view time transfer using GNSS satellites to maintain the time link of geodetic active control points to UTC as well as to determine receiver internal clock characteristics.

Smearing time: Critical temporality and corporate ontology

Since 1972 a leap second has been introduced into global time standardization systems, due to the discrepancy between Coordinated Universal Time and International Atomic Time. Until recently, the leap second has been a consensual, if mildly uncanny adjustment, a para-governmental temporal wobble. Google's explanation of its actions with regard to the insertion of a leap second smeared into its Network Time Protocol servers is couched in terms of a period extending initially over 20 h, ultimately reaching 24 h. Google is intent on taking ownership of the smear and transducing it into a technologically stabilised change. Although there are a number of different strategies of smearing time, Google advocates for its standard smear that it wants other digital giants like Bloomberg, Amazon and Microsoft to replicate. In this paper we first analyze Google's temporal strategy in terms of its affinities and departures from the classical view of time in Aristotle's core considerations in the Physics Book IV, in terms of a consonant enumeration but in our example at variable speeds/intervals, and then in terms of Wolfgang Ernst's conception of time-critical media. Leap seconds conform to Ernst's sense of kairotic time, an auspicious micro-moment that is both techno-mathematically pre-defined and decisive for ensuring operationality. Google executes smeared time-critical processes but wants to establish mastery over the measurement and manipulation of humanly imperceptible microtemporal events by inhabiting temporal ontology itself, proposing its practice, based on misleading its servers, as a model for other digital hegemons.