|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.
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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 F_Ultra-Wideband Operation
Sec. 15.521 Technical requirements applicable to all UWB devices.
(a) UWB devices may not be employed for the operation of toys.
Operation onboard an aircraft, a ship or a satellite is prohibited.
(b) Manufacturers and users are reminded of the provisions of
Sec. Sec. 15.203 and 15.204.
(c) Emissions from digital circuitry used to enable the operation of
the UWB transmitter shall comply with the limits in Sec. 15.209, rather
than the limits specified in this subpart, provided it can be clearly
demonstrated that those emissions from the UWB device are due solely to
emissions from digital circuitry contained within the transmitter and
that the emissions are not intended to be radiated from the
transmitter's antenna. Emissions from associated digital devices, as
defined in Sec. 15.3(k), e.g., emissions from digital circuitry used to
control additional functions or capabilities other than the UWB
transmission, are subject to the limits contained in Subpart B of this
(d) Within the tables in Sec. Sec. 15.509, 15.511, 15.513, 15.515,
15.517, and 15.519, the tighter emission limit applies at the band
edges. Radiated emission levels at and below 960 MHz are based on
measurements employing a CISPR quasi-peak detector. Radiated emission
levels above 960 MHz are based on RMS average measurements over a 1 MHz
resolution bandwidth. The RMS average measurement is based on the use of
a spectrum analyzer with a resolution bandwidth of 1 MHz, an RMS
detector, and a 1 millisecond or less averaging time. Unless otherwise
stated, if pulse gating is employed where the transmitter is quiescent
for intervals that are long compared to the nominal pulse repetition
interval, measurements shall be made with the pulse train gated on.
Alternative measurement procedures may be considered by the Commission.
(e) The frequency at which the highest radiated emission occurs,
fM, must be contained within the UWB bandwidth.
(f) Imaging systems may be employed only for the type of information
exchange described in their specific definitions contained in Sec.
15.503. The detection of tags or the transfer or data or voice
information is not permitted under the standards for imaging systems.
(g) When a peak measurement is required, it is acceptable to use a
resolution bandwidth other than the 50 MHz specified in this subpart.
This resolution bandwidth shall not be lower than 1 MHz or greater than
50 MHz, and the measurement shall be centered on the frequency at which
the highest radiated emission occurs, fM. If a resolution
bandwidth other than 50 MHz is employed, the peak EIRP limit shall be 20
log (RBW/50) dBm where RBW is the resolution bandwidth in megahertz that
is employed. This may be converted to a peak field strength level at 3
meters using E(dBuV/m) = P(dBm EIRP) + 95.2. If RBW is greater than 3
MHz, the application for certification filed with the Commission must
contain a detailed description of the test procedure, calibration of the
test setup, and the instrumentation employed in the testing.
(h) The highest frequency employed in Sec. 15.33 to determine the
frequency range over which radiated measurements are made shall be based
on the center frequency, fC, unless a higher frequency is
generated within the UWB device. For measuring emission levels, the
spectrum shall be investigated
from the lowest frequency generated in the UWB transmitter, without
going below 9 kHz, up to the frequency range shown in Sec. 15.33(a) or
up to fC + 3/(pulse width in seconds), whichever is higher.
There is no requirement to measure emissions beyond 40 GHz provided
fC is less than 10 GHz; beyond 100 GHz if fC is at
or above 10 GHz and below 30 GHz; or beyond 200 GHz if fC is
at or above 30 GHz.
(i) The prohibition in Sec. 2.201(f) and 15.5(d) of this chapter
against Class B (damped wave) emissions does not apply to UWB devices
operating under this subpart.
(j) Responsible parties are reminded of the other standards and
requirements cross referenced in Sec. 15.505, such as a limit on
emissions conducted onto the AC power lines.
[67 FR 34856, May 16, 2002, as amended at 68 FR 19751, Apr. 22, 2003; 70
FR 6776, Feb. 9, 2005]