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FCC Part 15 Radio Frequency Devices
Section 15.257

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
[CITE: 47CFR15.257]
[Page 829-830]
                       TITLE 47--TELECOMMUNICATION
                     Subpart C_Intentional Radiators
Sec. 15.257  Operation within the band 92-95 GHz.
    (a) Operation of devices under the provisions of this section is 
limited to indoor use;
    (1) Devices operating under the provisions of this section, by the 
nature of their design, must be capable of operation only indoors. The 
necessity to operate with a fixed indoor infrastructure, e.g., a 
transmitter that must be connected to the AC power lines, may be 
considered sufficient to demonstrate this.
    (2) The use of outdoor mounted antennas, e.g., antennas mounted on 
the outside of a building or on a telephone pole, or any other outdoors 
infrastructure is prohibited.
    (3) The emissions from equipment operated under this section shall 
not be intentionally directed outside of the building in which the 
equipment is located, such as through a window or a doorway.
    (4) Devices operating under the provisions of this section shall 
bear the following or similar statement in a conspicuous location on the 
device or in the instruction manual supplied with the device: ``This 
equipment may only be operated indoors. Operation outdoors is in 
violation of 47 U.S.C. 301 and could subject the operator to serious 
legal penalties.''
    (b) Operation under the provisions of this section is not permitted 
on aircraft or satellites.
[[Page 830]]
    (c) Within the 92-95 GHz bands, the emission levels shall not exceed 
the following:
    (1) The average power density of any emission, measured during the 
transmit interval, shall not exceed 9 uW/sq. cm, as measured at 3 meters 
from the radiating structure, and the peak power density of any emission 
shall not exceed 18 uW/sq. cm, as measured 3 meters from the radiating 
    (2) Peak power density shall be measured with an RF detector that 
has a detection bandwidth that encompasses the band being used and has a 
video bandwidth of at least 10 MHz, or uses an equivalent measurement 
    (3) The average emission limits shall be calculated based on the 
measured peak levels, over the actual time period during which 
transmission occurs.
    (d) Limits on spurious emissions:
    (1) The power density of any emissions outside the band being used 
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.
    (e) The total peak transmitter output power shall not exceed 500 mW.
    (f) Fundamental emissions must be contained within the frequency 
bands 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 
    (g) Regardless of the maximum EIRP and maximum 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 47 CFR 1.1307(b), 2.1091, and 2.1093, 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.
[69 FR 3265, Jan. 23, 2004]

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