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Standard frequency and time signal service

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Standard frequency and time signal radio station DCF77
Radiocommunication signal of the time signal transmitter station YVTO

Standard frequency and time signal service (short: SFTS) is, according to Article 1.53 of the International Telecommunication Union's (ITU) Radio Regulations (RR),[1] "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

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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)

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

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GTS-Module onboard ISS, handled by astronaut Vladimir Dezhurov

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),[2] 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

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The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations (edition 2012).[3]

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 with-in 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 3
19.95–20.05 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

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The following are the known HF time signal stations currently operational.

Call Sign Location Frequencies Time Signal Provided Time Signal Format Notes
ITU-R Standard Frequency and Time Signal services
BPM Pucheng, China 2.5, 5, 10, & 15 MHz ITU-R TF.768-5[4]
BSF Chung-Li, Taiwan, Rep. of China 5 and 15 MHz
EBC Cádiz 4.998 MHz
HLA Taejon, Republic of Korea 5 MHz ITU-R TF.768-5[4]
IAM Rome, Italy 5 MHz ITU-R TF.768-5[4]
LOL Buenos Aires, Argentina 5, 10, & 15 MHz ITU-R TF.768-5[4]
MIKES Espoo, Finland 25 MHz
OMA Prague, Czech Republic 2.5 MHz Discontinued in 1995
PPE Rio de Janeiro, Brazil 10 MHz
RWM Moscow, Russia 4.996, 9.996, 14.996 MHz ITU-R TF.768-5[4]
WWV Fort Collins, Colorado, United States 2.5, 5, 10, 15, & 20 MHz ITU-R TF.768-5[4]
WWVH Kekaha, Kauai, Hawaii, United States 2.5, 5, 10, & 15 MHz ITU-R TF.768-5[4]
YVTO Caracas, Venezuela 5 MHz
Time signal stations on non-standard frequencies
CHU Ottawa, Ontario, Canada 3.33, 7.85, 14.67 MHz

United States

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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)[1]

See also

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References

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  1. ^ a b ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.53, definition: standard frequency and time signal service
  2. ^ ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.54, definition: standard frequency and time signal-satellite service
  3. ^ ITU Radio Regulations, CHAPTER II – Frequencies, ARTICLE 5 Frequency allocations, Section IV – Table of Frequency Allocations
  4. ^ a b c d e f g "RECOMMENDATION ITU-R TF.768-5 Standard frequencies and time signals" (PDF). Archived from the original (PDF) on 2017-12-22.
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