Standard frequency and time signal service (short: SFTS) is, according to Article 1.53 of the International Telecommunication Union's (ITU) Radio Regulations (RR),ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.53, definition: standard frequency and time signal service "A radiocommunication service for scientific, technical and other purposes, providing the transmission of specified frequencies, time signals, or both, of stated high precision, intended for general reception".

Classification In accordance with ITU Radio Regulations (article 1) variations of this radiocommunication service are classified as follows: Standard frequency and time signal service (article 1.53) Standard frequency and time signal-satellite service

In general this radiocommunication service uses radio stations as follows: Standard frequency and time signal stations (article 1.95)

Standard frequency and time signal-satellite service

Standard frequency and time signal-satellite service (short: SFTSS) is, according to Article 1.54 of the International Telecommunication Union's (ITU) Radio Regulations (RR),ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.54, definition: standard frequency and time signal-satellite service defined as a radiocommunication service using space stations on earth satellites for the same purposes as those of the standard frequency and time signal service.

An example to this were experiments of time synchronisation (Global Transmission Services GTS-2) onboard International Space Station. However, in accordance to the ubiquitous availability, GNSS-satellite signals will be used in practice (see also: GPS-disciplined oscillator).

Frequency allocation The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations (edition 2012).ITU Radio Regulations, CHAPTER II – Frequencies, ARTICLE 5 Frequency allocations, Section IV – Table of Frequency Allocations

In order to improve harmonisation in spectrum utilisation, the majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations which is within the responsibility of the appropriate national administration. The allocation might be primary, secondary, exclusive, and shared. primary allocation: is indicated by writing in capital letters (see example below) secondary allocation: is indicated by small letters

Example of frequency allocation Allocation to services Region 1 Region 2 Region 319.95–20.05 MHz        STANDARD FREQUENCY AND TIME SIGNAL (20 MHz)2 498-2 501 MHz        STANDARD FREQUENCY AND TIME SIGNAL (2 500 MHz)4 995–5 003 MHz        STANDARD FREQUENCY AND TIME SIGNAL (5 000 MHz)5 003–5 005 MHz        STANDARD FREQUENCY AND TIME SIGNAL Space research 9 995–10 003 MHz      STANDARD FREQUENCY AND TIME SIGNAL (10 000 MHz)10 003–10 005 MHz    STANDARD FREQUENCY AND TIME SIGNAL Space research 14 990–15 005 MHz    STANDARD FREQUENCY AND TIME SIGNAL (15 000 MHz)15 005–15 010 MHz    STANDARD FREQUENCY AND TIME SIGNAL Space research 19 990–19 995 MHz    STANDARD FREQUENCY AND TIME SIGNAL Space research 19 995–20 010 MHz    STANDARD FREQUENCY AND TIME SIGNAL (20 000 MHz)24 990–25 005 MHz    STANDARD FREQUENCY AND TIME SIGNAL (25 000 MHz)25 005–25 010 MHz    STANDARD FREQUENCY AND TIME SIGNAL Space research

Time signals in use The following are the known HF time signal stations currently operational. +Call SignLocationFrequenciesTime Signal ProvidedTime Signal FormatNotesITU-R Standard Frequency and Time Signal servicesBPMPucheng, China2.5, 5, 10, & 15 MHzITU-R TF.768-5BSFChung-Li, Taiwan, Rep. of China5 and 15 MHzEBCCádiz4.998 MHzHLATaejon, Republic of Korea5 MHzITU-R TF.768-5IAMRome, Italy5 MHzITU-R TF.768-5LOLBuenos Aires, Argentina5, 10, & 15 MHzITU-R TF.768-5MIKESEspoo, Finland25 MHzOMAPrague, Czech Republic2.5 MHzDiscontinued in 1995PPERio de Janeiro, Brazil10 MHzRWMMoscow, Russia4.996, 9.996, 14.996 MHzITU-R TF.768-5WWVFort Collins, Colorado, United States2.5, 5, 10, 15, & 20 MHzITU-R TF.768-5WWVHKekaha, Kauai, Hawaii, United States2.5, 5, 10, & 15 MHzITU-R TF.768-5YVTOCaracas, Venezuela5 MHz

United States The Standard Time and Frequency Signal (STFS) is a Radiocommunication service providing the transmission of specified frequency and time signal, of stated high precision, intended for general reception in the United States and beyond. The radio signals are broadcast on very precise carrier frequencies by the U.S. Naval Observatory and the National Institute of Standards and Technology (NIST), formerly the National Bureau of Standards (NBS). The technical specification of that particular service is in line to the provisions of the International Telecommunication Union's (ITU) Radio Regulations (RR)

See also Time synchronization in North America Radio Clock Time_signal#Radio_time_sources

References

External links NIST Time and Frequency Division NPL India Time and Frequency StandardsBad Link