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International & national Spectrum Managment

International & national Spectrum Managment. Harvey S. Liszt NRAO, CHARLOTTESVILLE. What is it, exactly?. ‘Everyone’ knows that there is heavy demand on the finite resources of the RF spectrum So, use of the spectrum is heavily regulated to prevent interference among users and uses

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International & national Spectrum Managment

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  1. International & nationalSpectrum Managment Harvey S. Liszt NRAO, CHARLOTTESVILLE Arecibo July 2005

  2. What is it, exactly? • ‘Everyone’ knows that there is heavy demand on the finite resources of the RF spectrum • So, use of the spectrum is heavily regulated to prevent interference among users and uses • Making the regulations work/making new regulations is called “spectrum management” • The lowliest job at any observatory • There are far more “spectrum managers” than astronomers (in the real world, that is) Arecibo July 2005

  3. What is interference? • Interference is unwanted signal occurring in a band which has been allocated to other uses • When you observe outside the bands allocated to radio astronomy you may see intentional radiation which is someone else’s signal • Inside a RA band, unwanted signal is quite likely to be generated by the observatory • Interference is what happens when SM FAILS Arecibo July 2005

  4. What is an allocation • Spectrum bands are allocated to ’services’ • Service = purpose or application • Most services are ‘active’ – they transmit • Radio astronomy and Earth-sensing are ‘passive’ • RAS and EE-SS (passive) only listen • Radar astronomy and EE-SS (active) also transmit but are distinct • Concept of “use” elusive for passive services • FCC considers spectrum “unused” just where we work best Arecibo July 2005

  5. Examples of services • Radiolocation = radar • Radionavigation • Radio Navigation Satellite Service = GPS • Fixed service (terrestrial point to point) • Fixed-satellite service (space-earth, earth-space) • terminals on 7-11’s, home satellite internet • Mobile-satellite service (satellite phones) • Broadcasting (TV) – known as the BS Arecibo July 2005

  6. What kind of service is RAS? • 1.5 radio waves or hertzian waves:  Electromagnetic waves of frequencies arbitrarily lower than 3 000 GHz, propagated in space without artificial guide. [Radio extends to 100m!] • 1.6 radiocommunication:  Telecommunication by means of radio waves. • 1.7 terrestrial radiocommunication:  Any radio- communication otherthan space radiocommunication or radio astronomy. • 1.13 radio astronomy:  Astronomy based on the reception of radio waves of cosmic origin. • [THESE ARE FROM THE RADIO REGULATIONS] Arecibo July 2005

  7. How does RAS operate? • 1.16 allocation (of a frequency band): Entry in the Table of FrequencyAllocations of a given frequency band for the purpose of its use by one or more terrestrial or space radiocommunication services or the radio astronomy service under specified conditions. This term shall also be applied to the frequency band concerned. Arecibo July 2005

  8. How does RAS operate? • 1.16 allocation (of a frequency band): Entry in the Table of FrequencyAllocations of a given frequency band for the purpose of its use by one or more terrestrial or space radiocommunication services or the radio astronomy service under specified conditions. This term shall also be applied to the frequency band concerned. • 4.6 For the purpose of resolving cases of harmful interference, the radio astronomy service shall be treated as a radiocommunication service. However, protection from services in other bands shall be afforded the radio astronomy service only to the extent that such services are afforded protection from each other. Arecibo July 2005

  9. How does RAS operate? • 1.16 allocation (of a frequency band): Entry in the Table of FrequencyAllocations of a given frequency band for the purpose of its use by one or more terrestrial or space radiocommunication services or the radio astronomy service under specified conditions. This term shall also be applied to the frequency band concerned. • 4.6 For the purpose of resolving cases of harmful interference, the radio astronomy service shall be treated as a radiocommunication service. However, protection from services in other bands shall be afforded the radio astronomy service only to the extent that such services are afforded protection from each other. • Bottom line: RAS has standing only to the extent that it may experience interference, which can only happen inside RAS bands, so having allocations is necessary to participation in spectrum management Arecibo July 2005

  10. How does RAS operate? • 4.4 Administrations of the Member States shall not assign to a station anyfrequency in derogation of either the Table of Frequency Allocations in this Chapter or the other provisions of these Regulations, except on the express condition that such a station, when using such a frequency assignment, shall not cause harmful interference to, and shall not claim protection from harmful interference caused by, a station operating in accordance with the provisions of the Constitution, the Convention and these Regulations Arecibo July 2005

  11. How does RAS operate? • 4.4 Administrations of the Member States shall not assign to a station anyfrequency in derogation of either the Table of Frequency Allocations in this Chapter or the other provisions of these Regulations, except on the express condition that such a station, when using such a frequency assignment, shall not cause harmful interference to, and shall not claim protection from harmful interference caused by, a station operating in accordance with the provisions of the Constitution, the Convention and these Regulations • Bottom line: RAS is free to observe in any band but may cry “foul” only when there is ‘harmful interference’ to RAS in RAS bands. Arecibo July 2005

  12. RAS is Unique • RAS is the only service which uses spectrum outside its own allocated bands • Only service which uses practitioners as its amateurish spectrum managers Arecibo July 2005

  13. The world is flat– ITU-R Regions Arecibo July 2005

  14. Part of the FCC version of the frequency table Arecibo July 2005

  15. Part of the FCC version of the frequency table Arecibo July 2005

  16. Part of the FCC version of the frequency table Arecibo July 2005

  17. Part of the FCC version of the frequency table Arecibo July 2005

  18. Part of the FCC version of the frequency table Arecibo July 2005

  19. Deconstruction Arecibo July 2005

  20. Deconstruction Arecibo July 2005

  21. Arecibo July 2005

  22. Arecibo July 2005

  23. WRC00 Allocations now extend up to 275 GHZ Arecibo July 2005

  24. Arecibo July 2005

  25. Some lesser protections Arecibo July 2005

  26. US74 … Catch 22? Arecibo July 2005

  27. US74 • FCC has considered cell phones on planes • 2nd harmonic in ‘protected’ OH band @ 1665 • 300 commercial aircraft are in direct line of sight to GB at any moment during a typical day Arecibo July 2005

  28. That’s the status quo – what’s it to you? • When you find an extraneous signal in your data, YOU can go to the frequency allocation table and see what is transmitting there! • If YOU were pointing the GBT toward the geosynchronous satellite belt and searching for a H2O maser in a galaxy at z = 0.66, YOU would find that this band is used for fixed-satellite service downlinks to VSAT’s! Arecibo July 2005

  29. What’s the process? • All countries are sovereign inside their border • Radio waves always know where to stop, eh? • But no country can operate a satellite transmitter without ITU-R permission • Border issues are often important • So the most general set of rules, the Radio Regulations, is an international treaty, renegotiated every 4-5 years at a UN organ. Arecibo July 2005

  30. The ITU-R • A UN agency in Geneva Arecibo July 2005

  31. The ITU-R • A UN agency in Geneva Arecibo July 2005

  32. The ITU-R • A UN agency in Geneva Arecibo July 2005

  33. The ITU-R • A UN agency in Geneva Arecibo July 2005

  34. The ITU-R • A UN agency in Geneva Entire ITU-R structure mirrored in US USWP7A,B,C,D Arecibo July 2005

  35. The world is flat-- ITU Regions Arecibo July 2005

  36. CEPT CITEL Arab group APT Regional Groups Arecibo July 2005

  37. cept craf citel corf Arab group apt rafcap For RAS, too Arecibo July 2005

  38. And the IUCAF umbrella • IUCAF • ICSU-chartered for IAU, COSPAR, URSI • Historically, the vehicle for RAS representation • Now being pressured to be more interdisciplinary • http://www.iucaf.org Arecibo July 2005

  39. What’s hot now? • RAS is bringing sensitive broadband instruments online opening new bands • Some of these bands are becoming toxic • High power orbiting radars, 1-100 GHz • Cloud-mapping (CloudSat 94.05 GHz) • TerraSar-X earth mapping SAR at 9.3-9.9 GHz • Could burn up a RAS receiver in the (statistically) unlikely event of a main-beam encounter Arecibo July 2005

  40. Where will it end • Our operations are being pushed back onto reservations and very out of the way places • In spectrum too, above 80 GHz is where RA has widest allocations • We are creating and trying to get more recognition for Radio Quiet Zones and operation at frequencies > 275 GHz • At present, no RQZ will protect you from a satellite or airplane, however toxic. Arecibo July 2005

  41. Where will it end • Worrying ‘too much’ is just crazy-making • Worrying too little would be dangerous • And illegal, being careful is in the Radio Regs • We haven’t found effective means of mitigating unwanted emissions, except to avoid them • We’re still working, despite ‘encroachments’ • If we were forced into space, we’d become vastly richer overnight Arecibo July 2005

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