Effective Date: September 22, 2014
Expiration Date: September 22, 2026
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4.1.1 The probability of harmful RFI increases as more demands for frequency assignments are placed in the RF spectrum. In an attempt to meet these demands and to optimize the use of the spectrum, the space between channels is minimized within the limitations imposed by the state-of-the-art development of electronic equipment. The same frequencies are often shared by users separated geographically, or the same frequencies may be assigned to two or more users on a time-share basis. Because of this frequency sharing, some interference can be expected (and even tolerated) since clear channels are not ordinarily available within the overcrowded RF spectrum.
4.1.2 Occurrences of interference should be investigated initially by the Center/Facility Spectrum Manager. Reports of harmful interference or jamming of NASA emitters should normally be distributed by the Center/Facility Spectrum Manager as follows:
a. At the impacted Center:
(1) Security Office
(2) Office of Safety and Mission Assurance
(3) Occupational Health Office
b. At the Agency level:
(1) National Spectrum Program Manager
(2) HQ Office of Security and Program Protection
(3) HQ Office of Inspector General
(4) HQ Office of the Chief Health and Medical Officer
4.1.3 Consideration should also be given to including intentional interference as an information technology security incident, which needs to be reported to the NASA Incident Response Center (NASIRC) and the Office of Inspector General Computer Crimes unit. Requests for the assignment of replacement frequencies are made only if the interference is prolonged and disruptive and cannot be cleared through normal procedures.
4.1.4 The Center/Facility Spectrum Manager shall not be responsible for any interference caused to Wi-Fi or IEEE 802.11 devices or other unlicensed devices (i.e., FCC Part 15 or NTIA Annex K devices).
4.2.1 Radio Frequency Users
a. Normally, the NASA frequency user will be the first to become aware of RFI, and a judgment is made of how the observed RFI affects their operation.
b. If the interference is such that it cannot be tolerated, radio frequency users should proceed in the following manner:
(1) Step 1: Thoroughly check the affected equipment to ensure that the equipment is operating properly and the RFI is not being generated internally or on the site.
(2) Step 2: If possible, identify by call sign (or other identification) the station causing the interference.
(3) Step 3: Measure the frequency or band of frequencies causing the interference.
(4) Step 4: If possible, determine the type of emission and the type of traffic being transmitted.
(5) Step 5: If possible, measure the bandwidth of the interfering signal (highest and lowest frequencies) using calibrated test equipment (i.e., spectrum analyzer/receiver with current metrology date affixed to test equipment) and note the type of equipment used for measurement.
(6) Step 6: If possible, determine the frequency of occurrence, duration of the interfering signal (i.e., continuous, intermittent, etc.), time of day of occurrence, and other circumstances to support the investigation.
(7) Step 7: Measure the interference signal strength.
(8) Step 8: Determine the nature or severity of the interference. Indicate the impact to operations including the severity of data loss or data degradation due to the interference.
(9) Step 9: After the information in Steps 2 through 8 have been obtained, report this data to the Center/Facility Spectrum Manager together with a formal request to clear the interference.
(10) Step 10: Supply the Center/Facility Spectrum Manager with any additional information that is necessary or may be useful in identifying and clearing the RFI (e.g., audio recordings or spectrum analyzer screen captures).
(11) Step 11: Contact the Center Security Office to determine if there are any other ramifications due to national security or law enforcement activity.
4.2.2 Center/Facility Spectrum Managers
a. The Center/Facility Spectrum Manager will make every effort to clear the interference at the Center before requesting assistance from the National Spectrum Program Manager.
b. Center/Facility Spectrum Managers should follow the appropriate procedures listed below to clear cases of interference to Agency operations:
(1) Step 1: Check the information supplied by the frequency user to ensure that it is as complete as possible. Request additional information from the user as required for filing the standard RFI report (See Step 6).
(2) Step 2: If the station can be identified, contact the interfering station directly and attempt to clear the interference through coordination with the station manager. If the interference originates from a foreign (non-U.S.) source, contact the National Spectrum Program Manager for further assistance (see paragraph 4.2 e (2) and (3)).
(3) Step 3: If direct contact with the interfering station is unsuccessful, and the interference appears to be from a non-Federal station, request assistance from the nearest FCC monitoring station as required to coordinate efforts to clear the interference. If the interference appears to be in the vicinity of an airport, contact the nearest FAA representative for assistance.
(4) Step 4: If the interference is encountered on or from a DoD Test Range, report the RFI to the local DoD Test Range Spectrum Manager for resolution. If there is no satisfactory resolution, then elevate the RFI to the DoD Area Frequency Coordinator (AFC) (see NTIA Manual, Table 8.3.26) in accordance with appropriate range communications instructions.
(5) Step 5: If all attempts to clear the interference through local coordination fail, report the RFI to the National Spectrum Program Manager in accordance with Steps 6 and 7 below.
(6) Step 6: Forward a message directly to the National Spectrum Program Manager. Use the standard RFI reporting format shown in Figure 4-1 for listing the particulars of the interference.
(7) Step 7: When practicable, forward a follow-up letter to the National Spectrum Program Manager. Reference the message by number, date, and time, and include the same information as the message together with a detailed report of local action taken to eliminate the interference.
c. The Center/Facility Spectrum Manager should cooperate fully with non-NASA spectrum users in resolving RFI that may be caused by emissions from within the local Center. â??
Figure 4-1 Standard RFI Reporting Format
4.2.3 National Spectrum Program Manager
a. When an RFI problem cannot be resolved at the Center, the National Spectrum Program Manager shall attempt to clear the interference through direct coordination with other Agencies if the problem is a national one, or indirectly with the assistance of the FCC or the NTIA if the problem is either international or the result of a non-Government system.
b. The National Spectrum Program Manager should follow the steps below as they apply to the particular situation: (1) Step 1: If the RFI is caused by a non-Federal station (or an unknown station) operating in the United States and its Possessions, notify the FCC directly, and provide such information and assistance required to enable the FCC to clear the interference.
(2) Step 2: If the RFI is caused by a station operated by another agency or department of the U.S. Government, refer the matter to the IRAC, including a full report of the interference and a request for action or assistance, as required.
(3) Step 3: If the RFI is caused by a station of another nation operating outside the United States and its Possessions, refer the matter to IRAC or to NTIA. NTIA or the FCC will assume the coordination necessary to resolve the problem at the International level through the ITU, if required.
c. The National Spectrum Program Manager should cooperate fully with non-NASA spectrum users in resolving RFI that may be caused by emissions from within the local Center.
4.2.4 Interference From Foreign (Non-U.S.) Sources
a. All NASA flight projects should follow the procedures for the management of RFI situations, outlined earlier in this chapter, except when the interference is believed to originate from a foreign (non-U.S.) source.
b. In the case of interference from a foreign (non-U.S.) source, the National Spectrum Program Manager, in consultation with the International Spectrum Program Manager, shall use the information supplied in the standard RFI report to apprise appropriate spectrum administration offices (e.g., NTIA, FCC, U.S. Department of State) of the interference, its nature, source, and the need for cessation.
c. In the case where interference from a foreign (non-U.S.) source is jeopardizing the return of unique scientific data or the survival of a spacecraft (e.g., spacecraft emergency), the International Spectrum Program Manager shall contact appropriate Space Frequency Coordination Group (SFCG) members to try to secure cessation of the interfering transmission. This action is to be followed up with a formal report to the appropriate spectrum administration office (e.g., NTIA, FCC or U.S. Department of State).
4.2.5 NASA/ESA/JAXA RFI Coordination Procedures
Coordination of spectrum use between NASA, the European Space Agency (ESA), and the Japanese Aerospace and Exploration Administration (JAXA) will conform to the procedures outlined in the appropriate coordination manual. Such coordination shall be the responsibility of the International Spectrum Program Manager in consultation with affected Center/Facility Spectrum Managers and the National Spectrum Program Manager.
4.2.6 Space Frequency Coordination Group (SFCG)
a. The SFCG was established to provide a less formal and more flexible environment than the International Telecommunication Union for the solution of frequency management problems encountered by member space agencies. The Terms of Reference for SFCG are given in Appendix I.
b. The SFCG is concerned with the effective use and management of those radio frequency bands as allocated in the ITU RR for radio services within the scope of Radiocommunication Sector Study Group 7 (see Appendix J). In particular, the services of interest to the SFCG include space research, Earth-exploration satellites, meteorological satellites, space operations, data relay satellites, radio-navigation satellites, and radio astronomy (including radar astronomy) to the extent that they are relevant to spacecraft missions. Within the formal framework of the Radio Regulations, there is the need and opportunity for international informal agreement among participating space agencies concerning assignment of specific frequencies and related technical issues. The International Spectrum Program Manager, in consultation with the affected Center/Facility Spectrum Managers, shall facilitate this coordination. The Goddard Space Flight Center is responsible for the maintenance of the SFCG radio frequency database. Each Center/Facility Spectrum Manager is responsible for the analysis of NASA programs under their cognizance with the SFCG data.
c. The principal result of SFCG meetings is the adoption of resolutions and recommendations that express technical and administrative agreements. These agreements may be used by space agencies to make best use of allocated bands and to avoid interference.
4.2.7 International Space Station (ISS) Radio-Frequency Coordination Procedures for radio-frequency coordination for the International Space Station (ISS) are defined in NASA publication SSP 50423, ISS Radio Frequency Coordination Manual.
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