Content deleted Content added
mNo edit summary |
BobMeyer73 (talk | contribs) |
||
| (35 intermediate revisions by 24 users not shown) | |||
Line 1:
{{Short description|Radiocommunication service for scientific and other purposes}}
{{main|Radio station|Radiocommunication service}}
[[File:Dcf77.jpg|thumb|300px|{{center|Standard frequency and time signal radio station [[DCF77]]}}]]
[[File:YVTO time.ogg|thumb|{{center|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|International Telecommunication Union's]] (ITU) [[ITU Radio Regulations|Radio Regulations]] (RR),<ref name="ReferenceA">ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.53, definition: ''standard frequency and time signal service''</ref> "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:<br />
'''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==
[[File:Dezhurov GTS-21.jpg|thumb|250px|{{center|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|International Telecommunication Union's]] (ITU) [[ITU Radio Regulations|Radio Regulations]] (RR),<ref>ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.54, definition: ''standard frequency and time signal-satellite service''</ref> defined as ''A radiocommunication service using [[space radio station|space stations]] on earth [[satellite]]s 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).<ref>''ITU Radio Regulations, CHAPTER II – Frequencies, ARTICLE 5 Frequency allocations, Section IV – Table of Frequency Allocations''</ref>
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]]:
{| class=wikitable
|- bgcolor="#CCCCCC" align="center"
|align="center" colspan="3"| '''Allocation to services'''
|- align="center"
| [[International Telecommunication Union region|Region 1]] || Region 2 || Region 3
|-
|colspan="3"|19.95–20.05 [[kHz|MHz]] '''STANDARD FREQUENCY AND TIME SIGNAL (20 MHz)'''
|-
|colspan="3"|2 498-2 501 MHz STANDARD FREQUENCY AND TIME SIGNAL (2 500 MHz)
|-
|colspan="3"|4 995–5 003 MHz STANDARD FREQUENCY AND TIME SIGNAL (5 000 MHz)
|-
|colspan="3"|5 003–5 005 MHz STANDARD FREQUENCY AND TIME SIGNAL<br />
:::::: Space research
|-
|colspan="3"|9 995–10 003 MHz STANDARD FREQUENCY AND TIME SIGNAL (10 000 MHz)
|-
|colspan="3"|10 003–10 005 MHz STANDARD FREQUENCY AND TIME SIGNAL
:::::: Space research
|-
|colspan="3"|14 990–15 005 MHz STANDARD FREQUENCY AND TIME SIGNAL (15 000 MHz)
|-
|colspan="3"|15 005–15 010 MHz STANDARD FREQUENCY AND TIME SIGNAL<br />
:::::: Space research
|-
|colspan="3"|19 990–19 995 MHz STANDARD FREQUENCY AND TIME SIGNAL<br />
:::::: Space research
|-
|colspan="3"|19 995–20 010 MHz STANDARD FREQUENCY AND TIME SIGNAL (20 000 MHz)
|-
|colspan="3"|24 990–25 005 MHz STANDARD FREQUENCY AND TIME SIGNAL (25 000 MHz)
|-
|colspan="3"|25 005–25 010 MHz STANDARD FREQUENCY AND TIME SIGNAL<br />
:::::: Space research
|-
|}
== Time signals in use ==
The following are the known [[High frequency|HF]] time signal stations currently operational.
{| class="wikitable"
|+
!Call Sign
!Location
!Frequencies
!Time Signal Provided
!Time Signal Format
!Notes
|-
| colspan="6" |'''ITU-R Standard Frequency and Time Signal services'''
|-
|[[BPM (time service)|BPM]]
|Pucheng, China
|2.5, 5, 10, & 15 MHz
|
|
|ITU-R TF.768-5<ref name=":0">{{Cite web|url=https://www.itu.int/dms_pubrec/itu-r/rec/tf/R-REC-TF.768-5-200202-S!!PDF-E.pdf|title=RECOMMENDATION ITU-R TF.768-5 Standard frequencies and time signals|archive-url=https://web.archive.org/web/20171222053729/https://www.itu.int/dms_pubrec/itu-r/rec/tf/R-REC-TF.768-5-200202-S!!PDF-E.pdf|archive-date=2017-12-22|url-status=dead}}</ref>
|-
|BSF
|Chung-Li, Taiwan, Rep. of China
|5 and 15 MHz
|
|
|
|-
|EBC
|[[Cádiz]]
|4.998 MHz
|
|
|
|-
|[[HLA (radio station)|HLA]]
|Taejon, Republic of Korea
|5 MHz
|
|
|ITU-R TF.768-5<ref name=":0" />
|-
|IAM
|Rome, Italy
|5 MHz
|
|
|ITU-R TF.768-5<ref name=":0" />
|-
|LOL
|Buenos Aires, Argentina
|5, 10, & 15 MHz
|
|
|ITU-R TF.768-5<ref name=":0" />
|-
|MIKES
|[[Espoo, Finland]]
|25 MHz
|
|
|
|-
|[[OMA (time signal)|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<ref name=":0" />
|-
|[[WWV (radio station)|WWV]]
|Fort Collins, Colorado, United States
|2.5, 5, 10, 15, & 20 MHz
|
|
|ITU-R TF.768-5<ref name=":0" />
|-
|[[WWVH]]
|Kekaha, Kauai, Hawaii, United States
|2.5, 5, 10, & 15 MHz
|
|
|ITU-R TF.768-5<ref name=":0" />
|-
|[[YVTO]]
|Caracas, [[Venezuela]]
|5 MHz
|
|
|
|-
| colspan="6" |'''Time signal stations on non-standard frequencies'''
|-
|[[CHU (radio station)|CHU]]
|[[Ottawa, Ontario]], Canada
|3.33, 7.85, 14.67 MHz
|
|
|
|}
=== United States ===
The '''Standard Time and Frequency Signal''' (STFS) is a [[Radiocommunication service]] providing the transmission of specified [[frequency]] and [[time]] signal, of [[Standardization|stated]] high precision, intended for general reception in the United States and beyond. The radio signals are broadcast on very precise [[Carrier signal|carrier]] frequencies by the [[United States Naval Observatory|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|International Telecommunication Union's]] (ITU) [[ITU Radio Regulations|Radio Regulations]] (RR)<ref name="ReferenceA"/>
== See also ==
* [[Time synchronization in North America]]
* [[Radio Clock]]
* [[Time_signal#Radio_time_sources]]
==References ==
{{reflist}}
== External links ==
* [https://web.archive.org/web/20060421225303/http://tf.nist.gov/ NIST Time and Frequency Division]
* [http://www.nplindia.org/time-and-frequency-standards NPL India Time and Frequency Standards]'''Bad Link'''
{{Radiocommunication services ITU}}
[[Category:Radiocommunication services ITU]]
[[Category:Standards]]
[[Category:Time signals]]
| |||