|The Federal Communications Commission (FCC) is the authority
in the United States of America that creates and enforces the use of airwaves throughout the entire
radio frequency spectrum. This group of documents contains the entirety of the
FCC Part 15 regulations
that concern unlicensed radio frequency devices. As with all government documents, this material
is in the public domain and may be freely copied so long as the content is not changed. This copy
is provided as a convenience for RF Cafe visitors.
Click here for the
Table of Contents.
[Code of Federal Regulations]
[Title 47, Volume 1]
[Revised as of October 1, 2008]
From the U.S. Government Printing Office via GPO Access
CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION
PART 15_RADIO FREQUENCY DEVICES--Table of Contents
Subpart C_Intentional Radiators
Sec. 15.255 Operation within the band 57-64 GHz.
(a) Operation under the provisions of this section is not permitted
for the following products:
(1) Equipment used on aircraft or satellites.
(2) Field disturbance sensors, including vehicle radar systems,
unless the field disturbance sensors are employed for fixed operation.
For the purposes of this section, the reference to fixed operation
includes field disturbance sensors installed in fixed equipment, even if
the sensor itself moves within the equipment.
(b) Within the 57-64 GHz band, emission levels shall not exceed the
(1) For products other than fixed field disturbance sensors, the
average power density of any emission, measured during the transmit
interval, shall not exceed 9 [mu]W/cm\2\, as measured 3 meters from the
radiating structure, and the peak power density of any emission shall
not exceed 18 [mu]W/cm\2\, as measured 3 meters from the radiating
(2) For fixed field disturbance sensors that occupy 500 MHz or less
of bandwidth and that are contained wholly within the frequency band
61.0-61.5 GHz, the average power density of any emission, measured
during the transmit interval, shall not exceed 9 [mu]W/cm\2\, as
measured 3 meters from the radiating structure, and the peak power
density of any emission shall not exceed 18 [mu]W/cm\2\, as measured 3
meters from the radiating structure. In addition, the average power
density of any emission outside of the 61-61.5 GHz band, measured during
the transmit interval, but still within the 57-64 GHz band, shall not
exceed 9 nW/cm\2\, as measured 3 meters from the radiating structure,
and the peak power density of any emission shall not exceed 18 nW/cm\2\,
as measured three meters from the radiating structure.
(3) For fixed field disturbance sensors other than those operating
under the provisions of paragraph (b)(2) of this section, the peak
transmitter output power shall not exceed 0.1 mW and the peak power
density shall not exceed 9 nW/cm\2\ at a distance of 3 meters.
(4) Peak power density shall be measured with an RF detector that
has a detection bandwidth that encompasses the 57-64 GHz band and has a
video bandwidth of at least 10 MHz, or using an equivalent measurement
(5) The average emission levels shall be calculated, based on the
measured peak levels, over the actual time period during which
(c) Limits on spurious emissions:
(1) The power density of any emissions outside the 57-64 GHz band
shall consist solely of spurious emissions.
(2) Radiated emissions below 40 GHz shall not exceed the general
limits in Sec. 15.209.
(3) Between 40 GHz and 200 GHz, the level of these emissions shall
not exceed 90 pW/cm\2\ at a distance of 3 meters.
(4) The levels of the spurious emissions shall not exceed the level
of the fundamental emission.
(d) Only spurious emissions and transmissions related to a publicly-
accessible coordination channel, whose purpose is to coordinate
operation between diverse transmitters with a view towards reducing the
probability of interference throughout the 57-64 GHz band, are permitted
in the 57-57.05 GHz band.
Note to paragraph (d): The 57-57.05 GHz is reserved exclusively for
a publicly-accessible coordination channel. The development of standards
for this channel shall be performed pursuant to authorizations issued
under part 5 of this chapter.
(e) Except as specified elsewhere in this paragraph (e), the total
peak transmitter output power shall not exceed 500 mW.
(1) Transmitters with an emission bandwidth of less than 100 MHz
must limit their peak transmitter output power to the product of 500 mW
times their emission bandwidth divided by 100 MHz. For the purposes of
this paragraph (e)(1), emission bandwidth is defined as the
instantaneous frequency range occupied by a steady state radiated signal
with modulation, outside which the radiated power spectral density never
exceeds 6 dB below the maximum radiated power spectral density in the
band, as measured with a 100 kHz resolution bandwidth spectrum analyzer.
The center frequency must be stationary during the measurement interval,
even if not stationary during normal operation (e.g. for frequency
(2) Peak transmitter output power shall be measured with an RF
detector that has a detection bandwidth that encompasses the 57-64 GHz
band and that has a video bandwidth of at least 10 MHz, or using an
equivalent measurement method.
(3) For purposes of demonstrating compliance with this paragraph
(e), corrections to the transmitter output power may be made due to the
antenna and circuit loss.
(f) Fundamental emissions must be contained within the frequency
specified in this section during all conditions of operation. Equipment
is presumed to operate over the temperature range -20 to +50 degrees
celsius with an input voltage variation of 85% to 115% of rated input
voltage, unless justification is presented to demonstrate otherwise.
(g) Regardless of the power density levels permitted under this
section, devices operating under the provisions of this section are
subject to the radiofrequency radiation exposure requirements specified
in Sec. Sec. 1.1307(b), 2.1091 and 2.1093 of this chapter, as
appropriate. Applications for equipment authorization of devices
operating under this section must contain a statement confirming
compliance with these requirements for both fundamental emissions and
unwanted emissions. Technical information showing the basis for this
statement must be submitted to the Commission upon request.
(h) Any transmitter that has received the necessary FCC equipment
authorization under the rules of this chapter may be mounted in a group
installation for simultaneous operation with one or more other
transmitter(s) that have received the necessary FCC equipment
authorization, without any additional equipment authorization. However,
no transmitter operating under the provisions of this section may be
equipped with external phase-locking inputs that permit beam-forming
arrays to be realized.
(i) For all transmissions that emanate from inside of a building,
within any one second interval of signal transmission, each transmitter
with a peak output power equal to or greater than 0.1 mW or a peak power
density equal to or greater than 3 nW/cm\2\, as measured 3 meters from
the radiating structure, must transmit a transmitter identification at
least once. Each application for equipment authorization for equipment
that will be used inside of a building must declare that the equipment
contains the required transmitter identification feature and must
specify a method whereby interested parties can obtain sufficient
information, at no cost, to enable them to fully detect and decode this
transmitter identification information. Upon the completion of decoding,
the transmitter identification data block must provide the following
(1) FCC Identifier, which shall be programmed at the factory.
(2) Manufacturer's serial number, which shall be programmed at the
(3) Provision for at least 24 bytes of data relevant to the specific
device, which shall be field programmable. The grantee must implement a
method that makes it possible for users to specify and update this data.
The recommended content of this field is information to assist in
contacting the operator.
[63 FR 42279, Aug. 7, 1998, as amended at 66 FR 7409, Jan. 23, 2001; 68
FR 68547, Dec. 9, 2003]