Coordination of Transmitters Near the Radio Quiet Zone - ITS
Source: https://www.its.bldrdoc.gov/research/table-mountain/coordination-of-nearby-transmitters
Archived: 2026-04-23 17:37
Coordination of Transmitters Near the Radio Quiet Zone - ITS
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ITS Home
Research
Table Mountain
Facilities
Research Activities
Access to Site
Radio Quiet Zone Management
Coordination of Nearby Transmitters
Institute for Telecommunication Sciences
/
Research
/
Table Mountain
/ Coordination of Nearby Transmitters
The Table Mountain Field Site is designated by the FCC as a “Radio Quiet Zone” and is protected by Federal and State regulation from strong external radio signals. This restriction ensures that the Department of Commerce laboratories and research affiliates can study the characteristics and propagation of electromagnetic radiation in a real-world environment with minimal interference from uncontrolled sources of external radio interference.
This web page provides guidance for the coordination of
offsite transmissions
that may impact the Table Mountain Radio Quiet Zone. See also
47 CFR § 1.924 - Quiet zones
.
Researchers who use the field site will coordinate the
onsite transmitters
when requesting
access to the site
. Frequency coordination is not needed for computer peripherals, such as wireless keyboards, mice, printers, etc.
Table Mountain Radio Quiet Zone
Licensees and
applicants
planning to construct and operate a new or modified station at a permanent fixed location in the vicinity of Boulder County, Colorado are advised to give consideration, prior to filing applications, to the need to protect the Table Mountain Radio Quiet Zone from interference. To prevent degradation of the present ambient radio signal level at the site, the Department of Commerce seeks to ensure that the field strengths of any radiated signals (excluding reflected signals) received on this 1800 acre site (in the vicinity of coordinates 40°07′49.9″ North Latitude, 105°14′42.0″ West Longitude) resulting from new assignments (other than mobile stations) or from the modification or relocation of existing facilities do not exceed the values given in the following table:
Field Strength Limits for Table Mountain
Frequency Range
Field Strength (mV/m)
Power flux density (dBW/m
2
)
Below 540 kHz
10
−65.8
540 to 1600 kHz
20
−59.8
1.6 to 470 MHz
10
−65.8
470 to 890 MHz
30
−56.2
890 MHz and above
1
−85.8
Note:
Equivalent values of power flux density are calculated assuming free space characteristic impedance of 376.7Ω (120πΩ).
Advance consultation is recommended, particularly for
applicants
with no reliable data to indicate whether the field strength or
power flux density
figures in the above table would be exceeded by their proposed radio facilities. In general, coordination is recommended for:
Stations
located within 2.4 kilometers (1.5 miles) of the Table Mountain Radio Receiving Zone;
Stations
located within 4.8 kilometers (3 miles) transmitting with 50 watts or more
effective radiated power (ERP)
in the primary plane of polarization in the azimuthal direction of the Table Mountain Radio Receiving Zone;
Stations
located within 16 kilometers (10 miles) transmitting with 1 kW or more
ERP
in the primary plane of polarization in the azimuthal direction of the Table Mountain Radio Receiving Zone;
Stations
located within 80 kilometers (50 miles) transmitting with 25 kW or more
ERP
in the primary plane of polarization in the azimuthal direction of Table Mountain Receiving Zone.
Frequency Coordination Applications
If the transmitter is within the radius described above, provide the following:
Transmitter name
Transmitter owner
Transmitter site ID (USID)
Transmitter coordinates
Distance from Table Mountain Receiving Zone (from vicinity of 40-07-49.9 N lat / 105-14-42.0 W lon)
Project description
Transmit frequencies
Duty cycle
Signal bandwidth
Modulation type
Transmitter power (per polarization)
Antenna model
Antenna gain
Polarization
Beamwidth
Main beam direction (toward Quiet Zone)
Other beam directions (not toward Quiet Zone)
Transmitter height (electrical center) above ground level
Mechanical downtilt
Full antenna radiation patterns (0–359 degrees, horizontal/vertical)
Send this information to
frequencymanager@ntia.gov
. Allow 5–15 business days for a full propagation analysis to be performed with the information provided. Field strength will be calculated at the crossroads in the vicinity of coordinates 40°07′49.9″ North Latitude, 105°14′42.0″ West Longitude. Upon a favorable outcome (does not exceed TM limits), the frequency manager will provide a Letter of Successful Coordination to be submitted along with your application to the FCC.
The FCC will not screen
applications
to determine whether advance consultation has taken place. However, such consultation may avoid the filing of objections from the Department of Commerce or institution of proceedings to modify the
authorizations
of stations that radiate signals with a field strength or
power flux density
at the site in excess of those specified herein.
This coordination is based solely on technical information submitted to our office and not on the actual measured signal.
Questions
In advance of filing
applications
with the
Commission
,
applicants
are urged to communicate with the Radio Frequency Manager by sending an email to
frequencymanager@ntia.gov
or call 303-497-4220.
Skip to main content
↑ Back to top
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure.
The
https://
ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
ITS Home
Research
Table Mountain
Facilities
Research Activities
Access to Site
Radio Quiet Zone Management
Coordination of Nearby Transmitters
Institute for Telecommunication Sciences
/
Research
/
Table Mountain
/ Coordination of Nearby Transmitters
The Table Mountain Field Site is designated by the FCC as a “Radio Quiet Zone” and is protected by Federal and State regulation from strong external radio signals. This restriction ensures that the Department of Commerce laboratories and research affiliates can study the characteristics and propagation of electromagnetic radiation in a real-world environment with minimal interference from uncontrolled sources of external radio interference.
This web page provides guidance for the coordination of
offsite transmissions
that may impact the Table Mountain Radio Quiet Zone. See also
47 CFR § 1.924 - Quiet zones
.
Researchers who use the field site will coordinate the
onsite transmitters
when requesting
access to the site
. Frequency coordination is not needed for computer peripherals, such as wireless keyboards, mice, printers, etc.
Table Mountain Radio Quiet Zone
Licensees and
applicants
planning to construct and operate a new or modified station at a permanent fixed location in the vicinity of Boulder County, Colorado are advised to give consideration, prior to filing applications, to the need to protect the Table Mountain Radio Quiet Zone from interference. To prevent degradation of the present ambient radio signal level at the site, the Department of Commerce seeks to ensure that the field strengths of any radiated signals (excluding reflected signals) received on this 1800 acre site (in the vicinity of coordinates 40°07′49.9″ North Latitude, 105°14′42.0″ West Longitude) resulting from new assignments (other than mobile stations) or from the modification or relocation of existing facilities do not exceed the values given in the following table:
Field Strength Limits for Table Mountain
Frequency Range
Field Strength (mV/m)
Power flux density (dBW/m
2
)
Below 540 kHz
10
−65.8
540 to 1600 kHz
20
−59.8
1.6 to 470 MHz
10
−65.8
470 to 890 MHz
30
−56.2
890 MHz and above
1
−85.8
Note:
Equivalent values of power flux density are calculated assuming free space characteristic impedance of 376.7Ω (120πΩ).
Advance consultation is recommended, particularly for
applicants
with no reliable data to indicate whether the field strength or
power flux density
figures in the above table would be exceeded by their proposed radio facilities. In general, coordination is recommended for:
Stations
located within 2.4 kilometers (1.5 miles) of the Table Mountain Radio Receiving Zone;
Stations
located within 4.8 kilometers (3 miles) transmitting with 50 watts or more
effective radiated power (ERP)
in the primary plane of polarization in the azimuthal direction of the Table Mountain Radio Receiving Zone;
Stations
located within 16 kilometers (10 miles) transmitting with 1 kW or more
ERP
in the primary plane of polarization in the azimuthal direction of the Table Mountain Radio Receiving Zone;
Stations
located within 80 kilometers (50 miles) transmitting with 25 kW or more
ERP
in the primary plane of polarization in the azimuthal direction of Table Mountain Receiving Zone.
Frequency Coordination Applications
If the transmitter is within the radius described above, provide the following:
Transmitter name
Transmitter owner
Transmitter site ID (USID)
Transmitter coordinates
Distance from Table Mountain Receiving Zone (from vicinity of 40-07-49.9 N lat / 105-14-42.0 W lon)
Project description
Transmit frequencies
Duty cycle
Signal bandwidth
Modulation type
Transmitter power (per polarization)
Antenna model
Antenna gain
Polarization
Beamwidth
Main beam direction (toward Quiet Zone)
Other beam directions (not toward Quiet Zone)
Transmitter height (electrical center) above ground level
Mechanical downtilt
Full antenna radiation patterns (0–359 degrees, horizontal/vertical)
Send this information to
frequencymanager@ntia.gov
. Allow 5–15 business days for a full propagation analysis to be performed with the information provided. Field strength will be calculated at the crossroads in the vicinity of coordinates 40°07′49.9″ North Latitude, 105°14′42.0″ West Longitude. Upon a favorable outcome (does not exceed TM limits), the frequency manager will provide a Letter of Successful Coordination to be submitted along with your application to the FCC.
The FCC will not screen
applications
to determine whether advance consultation has taken place. However, such consultation may avoid the filing of objections from the Department of Commerce or institution of proceedings to modify the
authorizations
of stations that radiate signals with a field strength or
power flux density
at the site in excess of those specified herein.
This coordination is based solely on technical information submitted to our office and not on the actual measured signal.
Questions
In advance of filing
applications
with the
Commission
,
applicants
are urged to communicate with the Radio Frequency Manager by sending an email to
frequencymanager@ntia.gov
or call 303-497-4220.