FCC 27.53 Revised as of October 1, 2007
Goto Year:2006 |
2008
Sec. 27.53 Emission limits.
Link to an amendment published at 72 FR 48851 , Aug. 24, 2007.
(a) For operations in the bands 2305–2320 MHz and 2345–2360 MHz, the power
of any emission outside the licensee's frequency band(s) of operation shall
be attenuated below the transmitter power (P) within the licensed band(s) of
operation, measured in watts, by the following amounts:
(1) For fixed, land, and radiolocation land stations: By a factor not less
than 80 + 10 log (p) dB on all frequencies between 2320 and 2345 MHz;
(2) For mobile and radiolocation mobile stations: By a factor not less than
110 + 10 log (p) dB on all frequencies between 2320 and 2345 MHz;
(3) For fixed, land, mobile, radiolocation land and radiolocation mobile
stations: By a factor not less than 70 + 10 log (p) dB on all frequencies
below 2300 MHz and on all frequencies above 2370 MHz; and not less than 43 +
10 log (p) dB on all frequencies between 2300 and 2320 MHz and on all
frequencies between 2345 and 2370 MHz that are outside the licensed bands of
operation;
(4) Compliance with these provisions is based on the use of measurement
instrumentation employing a resolution bandwidth of 1 MHz or less, but at
least one percent of the emission bandwidth of the fundamental emission of
the transmitter, provided the measured energy is integrated over a 1 MHz
bandwidth;
(5) In complying with the requirements in Sec. 27.53(a)(1) and Sec. 27.53(a)(2), WCS
equipment that uses opposite sense circular polarization from that used by
Satellite DARS systems in the 2320–2345 MHz band shall be permitted an
allowance of 10 dB;
(6) When measuring the emission limits, the nominal carrier frequency shall
be adjusted as close to the edges, both upper and lower, of the licensee's
bands of operation as the design permits;
(7) The measurements of emission power can be expressed in peak or average
values, provided they are expressed in the same parameters as the
transmitter power;
(8) Waiver requests of any of the out-of-band emission limits in paragraphs
(a)(1) through (a)(7) of this section shall be entertained only if
interference protection equivalent to that afforded by the limits is shown;
(9) In the 2305–2315 MHz band, if portable devices comply with all of the
following requirements, then paragraph (a)(2) of this section shall not
apply to portable devices, which instead shall attenuate all emissions into
the 2320–2345 MHz band by a factor of not less than 93 + 10 log (p) dB:
(i) The portable device has a duty cycle of 12.5% or less, with at most a
312.5 microsecond pulse every 2.5 milliseconds;
(ii) The portable device must employ time division multiple access (TDMA)
technology;
(iii) The nominal peak transmit output power of the portable device is no
more than 200 milliwatts (25 milliwatts average power);
(iv) The portable device operates with the minimum power necessary for
successful communications;
(v) The nominal average base station transmit output power is no more than
800 milliwatts when the base station antennas is located at a height of at
least 8 meters (26.25 feet) above the ground;
(vi) Only fixed and portable devices and services may be provided:
vehicle-mounted units are not permitted; and
(vii) Transmitting antennas shall employ linear polarization or another
polarization that provides equivalent of better discrimination with respect
to a DARS antenna;
(10) The out-of-band emissions limits in paragraphs (a)(1) through (a)(9) of
this section may be modified by the private contractual agreement of all
affected licensees, who shall maintain a copy of the agreement in their
station files and disclose it to prospective assignees or transferees and,
upon request, to the Commission.
(b) For WCS Satellite DARS operations: The limits set forth in Sec. 25.202(f) of
this chapter shall apply, except that Satellite DARS operations shall be
limited to a maximum power flux density of −197 dBW/m^2 /4 kHz in the
2370–2390 MHz band at Arecibo, Puerto Rico.
(c) For operations in the 747 to 762 MHz band and the 777 to 792 MHz band,
the power of any emission outside the licensee's frequency band(s) of
operation shall be attenuated below the transmitter power (P) within the
licensed band(s) of operation, measured in watts, in accordance with the
following:
(1) On any frequency outside the 747 to 762 MHz band, the power of any
emission shall be attenuated outside the band below the transmitter power
(P) by at least 43 + 10 log (P) dB;
(2) On any frequency outside the 777 to 792 MHz band, the power of any
emission shall be attenuated outside the band below the transmitter power
(P) by at least 43 + 10 log (P) dB;
(3) On all frequencies between 764 to 776 MHz and 794 to 806 MHz, by a
factor not less than 76 + 10 log (P) dB in a 6.25 kHz band segment, for base
and fixed stations;
(4) On all frequencies between 764 to 776 MHz and 794 to 806 MHz, by a
factor not less than 65 + 10 log (P) dB in a 6.25 kHz band segment, for
mobile and portable stations;
(5) Compliance with the provisions of paragraphs (c)(1) and (c)(2) of this
section is based on the use of measurement instrumentation employing a
resolution bandwidth of 100 kHz or greater. However, in the 100 kHz bands
immediately outside and adjacent to the frequency block, a resolution
bandwidth of at least 30 kHz may be employed;
(6) Compliance with the provisions of paragraphs (c)(3) and (c)(4) of this
section is based on the use of measurement instrumentation such that the
reading taken with any resolution bandwidth setting should be adjusted to
indicate spectral energy in a 6.25 kHz segment.
(d) For operations in the 746–747 MHz, 762–764 MHz, 776–777 MHz, and 792–794
MHz bands, transmitters must meet the following emission limitations:
(1) The adjacent channel power (ACP) requirements for transmitters designed
for various channel sizes are shown in the following tables. Mobile station
requirements apply to handheld, car mounted and control station units. The
tables specify a value for the ACP as a function of the displacement from
the channel center frequency and measurement bandwidth. In the following
tables, “(s)” indicates a swept measurement may be used.
6.25 kHz Mobile Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
6.25 6.25 −40
12.5 6.25 −60
18.75 6.25 −60
25.00 6.25 −65
37.50 25.00 −65
62.50 25.00 −65
87.50 25.00 −65
150.00 100.00 −65
250.00 100.00 −65
350.00 100.00 −65
>400 kHz to 12 MHz 30(s) −75
12 MHz to paired receive band 30(s) −75
In the paired receive band 30(s) −100
12.5 kHz Mobile Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
9.375 6.25 −40
15.625 6.25 −60
21.875 6.25 −60
37.50 25.00 −60
62.50 25.00 −65
87.50 25.00 −65
150.00 100 −65
250.00 100 −65
350.00 100 −65
>400 to 12 MHz 30(s) −75
12 MHz to paired receive band 30(s) −75
In the paired receive band 30(s) −100
25 kHz Mobile Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
15.625 6.25 −40
21.875 6.25 −60
37.50 25 −60
62.50 25 −65
87.50 25 −65
150.00 100 −65
250.00 100 −65
350.00 100 −65
>400 kHz to 12 MHz 30(s) −75
12 MHz to paired receive band 30(s) −75
In the paired receive band 30(s) −100
150 kHz Mobile Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP relative (dBc)
100 50 −40
200 50 −50
300 50 −50
400 50 −50
600–1000 30(s) −60
1000 to receive band 30(s) −70
In the receive band 30(s) −100
6.25 kHz Base Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
6.25 6.25 −40
12.50 6.25 −60
18.75 6.25 −60
25.00 6.25 −65
37.50 25 −65
62.50 25 −65
87.50 25 −65
150.00 100 −65
250.00 100 −65
350.00 100 −65
>400 kHz to 12 MHz 30(s) −80
12 MHz to paired receive band 30(s) −80
In the paired receive band 30(s) −100
12.5 kHz Base Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
9.375 6.25 −40
15.625 6.25 −60
21.875 6.25 −60
37.5 25 −60
62.5 25 −65
87.5 25 −65
150 100 −65
250 100 −65
350.00 100 −65
>400 kHz to 12 MHz 30(s) −80
12 MHz to paired receive band 30(s) −80
In the paired receive band 30(s) −100
25 kHz Base Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
15.625 6.25 −40
21.875 6.25 −60
37.5 25 −60
62.5 25 −65
87.5 25 −65
150 100 −65
250 100 −65
350 100.00 −65
>400 kHz to 12 MHz 30(s) −80
12 MHz to paired receive band 30(s) −80
In the paired receive band 30(s) −100
150 kHz Base Transmitter ACP Requirements
Offset from center
frequency
(kHz) Measurement bandwidth
(kHz) Maximum ACP
(dBc)
100 50 −40
200 50 −50
300 50 −55
400 50 −60
600–1000 30(s) −65
1000 to receive band 30(s) −75 (continues at −6dB/oct
In the receive band 30(s) −100
(2) ACP measurement procedure. The following procedures are to be followed
for making ACP transmitter measurements. For time division multiple access
(TDMA) systems, the measurements are to be made under TDMA operation only
during time slots when the transmitter is on. All measurements must be made
at the input to the transmitter's antenna. Measurement bandwidth used below
implies an instrument that measures the power in many narrow bandwidths (
e.g., 300 Hz) and integrates these powers across a larger band to determine
power in the measurement bandwidth.
(i) Setting reference level. Using a spectrum analyzer capable of ACP
measurements, set the measurement bandwidth to the channel size. For
example, for a 6.25 kHz transmitter, set the measurement bandwidth to 6.25
kHz; for a 150 kHz transmitter, set the measurement bandwidth to 150 kHz.
Set the frequency offset of the measurement bandwidth to zero and adjust the
center frequency of the spectrum analyzer to give the power level in the
measurement bandwidth. Record this power level in dBm as the “reference
power level”.
(ii) Non-swept power measurement. Using a spectrum analyzer capable of ACP
measurements, set the measurement bandwidth as shown in the tables above.
Measure the ACP in dBm. These measurements should be made at maximum power.
Calculate the coupled power by subtracting the measurements made in this
step from the reference power measured in the previous step. The absolute
ACP values must be less than the values given in the table for each
condition above.
(iii) Swept power measurement. Set a spectrum analyzer to 30 kHz resolution
bandwidth, 1 MHz video bandwidth and sample mode detection. Sweep MHz from
the carrier frequency. Set the reference level to the RMS value of the
transmitter power and note the absolute power. The response at frequencies
greater than 600 kHz must be less than the values in the tables above.
(3) Out-of-band emission limit. On any frequency outside of the frequency
ranges covered by the ACP tables in this section, the power of any emission
must be reduced below the unmodulated carrier power (P) by at least 43 + 10
log (P) dB.
(4) Authorized bandwidth. Provided that the ACP requirements of this section
are met, applicants may request any authorized bandwidth that does not
exceed the channel size.
(e) For operations in the 746–764 MHz and 776–794 MHz bands, emissions in
the band 1559–1610 MHz shall be limited to −70 dBW/MHz equivalent
isotropically radiated power (EIRP) for wideband signals, and −80 dBW EIRP
for discrete emissions of less than 700 Hz bandwidth. For the purpose of
equipment authorization, a transmitter shall be tested with an antenna that
is representative of the type that will be used with the equipment in normal
operation.
(f) For operations in the 698–746 MHz band, the power of any emission
outside a licensee's frequency band(s) of operation shall be attenuated
below the transmitter power (P) within the licensed band(s) of operation,
measured in watts, by at least 43 + 10 log (P) dB. Compliance with this
provision is based on the use of measurement instrumentation employing a
resolution bandwidth of 100 kilohertz or greater. However, in the 100
kilohertz bands immediately outside and adjacent to a licensee's frequency
block, a resolution bandwidth of at least 30 kHz may be employed.
(g) For operations in the 1710–1755 MHz and 2110–2155 MHz bands, the power
of any emission outside a licensee's frequency block shall be attenuated
below the transmitter power (P) by at least 43 + 10 log[10](P) dB.
(1) Compliance with this provision is based on the use of measurement
instrumentation employing a resolution bandwidth of 1 megahertz or greater.
However, in the 1 megahertz bands immediately outside and adjacent to the
licensee's frequency block, a resolution bandwidth of at least one percent
of the emission bandwidth of the fundamental emission of the transmitter may
be employed. The emission bandwidth is defined as the width of the signal
between two points, one below the carrier center frequency and one above the
carrier center frequency, outside of which all emissions are attenuated at
least 26 dB below the transmitter power.
(2) When measuring the emission limits, the nominal carrier frequency shall
be adjusted as close to the licensee's frequency block edges, both upper and
lower, as the design permits.
(3) The measurements of emission power can be expressed in peak or average
values, provided they are expressed in the same parameters as the
transmitter power.
(h) When an emission outside of the authorized bandwidth causes harmful
interference, the Commission may, at its discretion, require greater
attenuation than specified in this section.
(i) For operations in the unpaired 1390–1392 MHz band and the paired
1392–1395 MHz and 1432–1435 MHz bands, the power of any emission outside the
licensee's frequency band(s) of operation shall be attenuated below the
transmitter power (P) by at least 43 + 10 log (P) dB. Compliance with these
provisions is based on the procedures described in paragraph (a)(4) of this
section.
(j) For operations in the 1670–1675 MHz band, the power of any emission
outside the licensee's frequency band(s) of operation shall be attenuated
below the transmitter power (P) by at least 43 + 10 log (P) dB. Compliance
with these provisions is based on the procedures described in paragraph
(a)(4) of this section.
(k) [Reserved]
(l) For BRS and EBS stations, the power of any emissions outside the
licensee's frequency bands of operation shall be attenuated below the
transmitter power (P) measured in watts. BRS and EBS stations that are not
in compliance with the standards below, after receiving a documented
interference complaint from an adjacent channel licensee, have 60 days to
coordinate with the affected licensee and meet a mutual resolution before
both parties employ a more rigorous emission mask.
(1) Prior to the transition, and thereafter, solely within the MBS, for
analog operations with an EIRP in excess of −9 dBW, the signal shall be
attenuated at the channel edges by at least 38 dB relative to the peak
visual carrier, then linearly sloping from that level to at least 60 dB of
attenuation at 1 MHz below the lower band edge and 0.5 MHz above the upper
band edge, and attenuated at least 60 dB at all other frequencies.
(2) For fixed and temporary fixed digital stations, the attenuation shall be
not less than 43 + 10 log (P) dB, unless a documented interference complaint
is received from an adjacent channel licensee. Provided that the complaint
cannot be mutually resolved between the parties, both licensees of existing
and new systems shall reduce their out-of-band emissions by at least 67 + 10
log (P) dB measured at 3 MHz from their channel's edges for distances
between stations exceeding 1.5 km. For stations separated by less than 1.5
km, the new licensee shall reduce attenuation at least 67 + 10 log (P) − 20
log(D[km]/1.5), or when colocated, limit the undesired signal level at the
affected licensee's base station receiver(s) at the colocation site to no
more than −107 dBm. Mobile Service Satellite licensees operating on
frequencies below 2495 MHz may also submit a documented interference
complaint against BRS licensees operating on channel BRS1 on the same terms
and conditions as adjacent channel BRS or EBS licensees.
(3) Prior to transition and thereafter solely within the MBS, and
notwithstanding paragraph (l)(2) of this section, the maximum out-of-band
power of a digital transmitter operating on a single 6 MHz channel with an
EIRP in excess of −9 dBW employing digital modulation for the primary
purpose of transmitting video programming shall be attenuated at the 6 MHz
channel edges at least 25 dB relative to the licensed average 6 MHz channel
power level, then attenuated along a linear slope to at least 40 dB at 250
kHz beyond the nearest channel edge, then attenuated along a linear slope
from that level to at least 60 dB at 3 MHz above the upper and below the
lower licensed channel edges, and attenuated at least 60 dB at all other
frequencies.
(4) For mobile digital stations, the attenuation factor shall be not less
than 43 + 10 log (P) dB at the channel edge and 55 + 10 log (P) dB at 5.5
MHz from the channel edges. Mobile Service Satellite licensees operating on
frequencies below 2495 MHz may also submit a documented interference
complaint against BRS licensees operating on channel BRS1 on the same terms
and conditions as adjacent channel BRS or EBS licensees.
(5) Notwithstanding the provisions of paragraphs (l)(2) and (l)(4) of this
section, prior to transition, a licensee may continue to operate facilities
deployed as of January 10, 2005 provided that such facilities operate in
compliance with the emission mask applicable to those services prior to
January 10, 2005.
(6) Measurement procedure. Compliance with these rules is based on the use
of measurement instrumentation employing a resolution bandwidth of 1 MHz or
greater. However, in the 1 MHz bands immediately outside and adjacent to the
frequency block a resolution bandwidth of at least one percent of the
emission bandwidth of the fundamental emission of the transmitter may be
employed. A narrower resolution bandwidth is permitted in all cases to
improve measurement accuracy provided the measured power is integrated over
the full required measurement bandwidth ( i.e. 1 MHz or 1 percent of
emission bandwidth, as specified). The emission bandwidth is defined as the
width of the signal between two points, one below the carrier center
frequency and one above the carrier center frequency, outside of which all
emissions are attenuated at least 26 dB below the transmitter power. With
respect to television operations, measurements must be made of the separate
visual and aural operating powers at sufficiently frequent intervals to
ensure compliance with the rules.
(7) Alternative out of band emission limit. Licensees in this service may
establish an alternative out of band emission limit to be used at specified
band edge(s) in specified geographical areas, in lieu of that set forth in
this section, pursuant to a private contractual arrangement of all affected
licensees and applicants. In this event, each party to such contract shall
maintain a copy of the contract in their station files and disclose it to
prospective assignees or transferees and, upon request, to the FCC.
(m) When an emission outside of the authorized bandwidth causes harmful
interference, the Commission may, at its discretion, require greater
attenuation than specified in this section.
[ 62 FR 16497 , Apr. 7, 1997, as amended at 65 FR 3147 , Jan. 20, 2000; 65 FR 17602 , Apr. 4, 2000; 65 FR 42883 , July 12, 2000; 67 FR 5511 , Feb. 6, 2002;
67 FR 41855 , June 20, 2002; 69 FR 5715 , Feb. 6, 2004; 69 FR 72033 , Dec. 10,
2004; 69 FR 77950 , Dec. 29, 2004; 70 FR 1190 , Jan. 6, 2005; 70 FR 21664 ,
Apr. 27, 2005; 71 FR 35190 , June 19, 2006]
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