47 CFR 25.208 - Power flux density limits.

Beta! The text on the eCFR tab represents the unofficial eCFR text at ecfr.gov.
§ 25.208 Power flux density limits.

(a) In the band 3650-4200 MHz, the power flux density at the Earth's surface produced by emissions from a space station for all conditions and for all methods of modulation shall not exceed the following values:

−152 dB(W/m 2) in any 4 kHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;
−152 (δ−5)/2 dB(W/m 2) in any 4 kHz band for angles of arrival δ (in degrees) between 5 and 25 degrees above the horizontal plane; and
−142 dB(W/m 2) in any 4 kHz band for angles of arrival between 25 and 90 degrees above the horizontal plane
These limits relate to the power flux density which would be obtained under assumed free-space propagation conditions.

(b) In the bands 10.95-11.2 and 11.45-11.7 GHz for GSO FSS space stations and 10.7-11.7 GHz for NGSO FSS space stations, the power flux-density at the Earth's surface produced by emissions from a space station for all conditions and for all methods of modulation shall not exceed the lower of the following values:

(1) −150 dB(W/m 2) in any 4 kHz band for angles of arrival between 0 and 5 degrees above the horizontal plane; −150 (δ−5)/2 dB(W/m 2) in any 4 kHz band for angles of arrival (δ) (in degrees) between 5 and 25 degrees above the horizontal plane; and −140 dB(W/m 2) in any 4 kHz band for angles of arrival between 25 and 90 degrees above the horizontal plane; or

(2) −126 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane; −126 (δ−5)/2 dB(W/m 2) in any 1 MHz band for angles of arrival (δ) (in degrees) between 5 and 25 degrees above the horizontal plane; and −116 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane.

Note to paragraph (b):

These limits relate to the power flux density, which would be obtained under assumed free-space propagation conditions.

(c) In the 17.7-17.8 GHz, 18.3-18.8 GHz, 19.3-19.7 GHz, 22.55-23.00 GHz, 23.00-23.55 GHz, and 24.45-24.75 GHz frequency bands, the power flux density at the Earth's surface produced by emissions from a space station for all conditions for all methods of modulation shall not exceed the following values:

(1) −115 dB (W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane.

(2) −115 0.5 (δ-5) dB (W/m 2) in any 1 MHz band for angles of arrival d (in degrees) between 5 and 25 degrees above the horizontal plane.

(3) −105 dB (W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane.

(d) In addition to the limits specified in paragraph (c) of this section, the power flux-density across the 200 MHz band 18.6-18.8 GHz produced at the Earth's surface by emissions from a space station under assumed free-space propagation conditions shall not exceed −95 dB (W/m 2) for all angles of arrival. This limit may be exceeded by up to 3 dB for no more than 5% of the time.

(e) In the 18.8-19.3 GHz frequency band, the power flux-density at the Earth's surface produced by emissions from a space station for all conditions and for all methods of modulation shall not exceed the following values:

−115−X dB(W/m 2 ÷ MHz) for 0° ≤δ <5°
−115−X ((10 X)/20)(δ−5)dB(W/m 2 ÷ MHz) for 5° ≤δ <25°
−105 dB(W/m 2 ÷ MHz) for 25° ≤δ <90°
Where:
δ: is the angle of arrival above the horizontal plane; and
X is defined as a function of the number of satellites in the non-GSO FSS constellation, n, as follows:
for n ≤50 X = 0 (dB)
for 50 <n ≤288 X = (5/119) (n − 50) (dB)
for n >288 X = (1/69) (n 402) (dB)

(f) [Reserved]

(g) In the 10.7-11.7 GHz and 11.7-12.2 GHz bands, the single-entry equivalent power-flux density in the space-to-Earth direction (EPFDdown), at any point on the Earth's surface, produced by emissions from all co-frequency space stations of a single non-geostationary-satellite orbit (NGSO) system operating in the Fixed-Satellite Service (FSS) shall not exceed the following limits for the given percentages of time. Tables 1G and 2G follow:

Table 1G - Single-Entry EPFDdown Limits for Protection of 0.6, 1.2, 3 and 10 Meter GSO FSS Earth Station Antennas 1 2

Frequency band (GHz) for International
Allocations
Single-entry EPFDdown dB(W/m 2) Percentage of time during which EPFDdown level may not be exceeded Reference bandwidth (kHz) Reference antenna diameter and reference radiation pattern 3
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −175.4
−174
−170.8
−165.3
−160.4
−160
−160
0
90
99
99.73
99.991
99.997
100
40 60 cm, Recommendation ITU-R S.1428.
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −181.9
−178.4
−173.4
−173
−164
−161.6
−161.4
−160.8
−160.5
−160
−160
0
99.5
99.74
99.857
99.954
99.984
99.991
99.997
99.997
99.9993
100
40 1.2 m, Recommendation ITU-R S.1428.
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −190.45
−189.45
−187.45
−182.4
−182
−168
−164
−162
−160
−160
0
90
99.5
99.7
99.855
99.971
99.988
99.995
99.999
100
40 3 m, Recommendation ITU-R S.1428.
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −195.45
−195.45
−190
−190
−172.5
−160
−160
0
99
99.65
99.71
99.99
99.998
100
40 10 m, Recommendation ITU-R S.1428.

1 In addition to the limits shown in Table 1G, the limits shown in Table 2G shall apply to all antenna sizes greater than 60 cm in the frequency bands listed in Table 1G.

2 For each reference antenna diameter, the limit consists of the complete curve on a plot which is linear in decibels for the EPFD levels and logarithmic for the time percentages, with straight lines joining the data points.

3 The earth station antenna reference radiation patterns are to be used only for the calculation of interference from NGSO FSS systems into GSO FSS systems.

Table 2G - Single-Entry EPFDdown Limits Radiated By Non-GSO FSS Systems At Certain Latitudes

100% of the time EPFDdown dB(W/(m 2/40 kHz)) Latitude (North or South in degrees)
-160 0 <| Latitude | ≤57.5.
-160 3.4 (57.5 − | Latitude |)/4 57.5 <| Latitude | ≤63.75
-165.3 63.75 ≤| Latitude |
Note to paragraph (g):

These limits relate to the equivalent power flux density, which would be obtained under free-space propagation conditions, for all conditions and for all methods of modulation.

(h) In the 10.7-11.7 GHz and 11.7-12.2 GHz bands, the aggregate equivalent power-flux density in the space-to-Earth direction (EPFDdown), at any point on the Earth's surface, produced by emissions from all co-frequency space stations of all non-geostationary-satellite orbit systems operating in the Fixed-Satellite Service (FSS) shall not exceed the following limits for the given percentages of time. Tables 1H and 2H follow:

Table 1H - Aggregate EPFDdown Limits for Protection of 0.6, 1.2, 3 and 10 Meter GSO FSS Earth Station Antennas 1

Frequency band (GHz) for International Allocations Aggregate EPFDdown dB(W/m 2) Percentage of time during which EPFDdown may not be
exceeded
Reference bandwidth (kHz) Reference antenna diameter and reference radiation pattern 2
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −170
−168.6
−165.3
−160.4
−160
−160
0
90
99
99.97
99.99
100
40 60 cm, Recommendation ITU-R S.1428.
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −176.5
−173
−164
−161.6
−164.4
−160.8
−160.5
−160
−160
0
99.5
99.84
99.945
99.97
99.99
99.99
99.9975
100
40 1.2 m, Recommendation ITU-R S.1428.
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −185
−184
−182
−168
−164
−162
−160
−160
0
90
99.5
99.9
99.96
99.982
99.997
100
40 3 m, Recommendation ITU-R S.1428.
10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −190
−190
−166
−160
−160
0
99
99.99
99.998
100
40 10 m, Recommendation ITU-R S.1428.

1 In addition to the limits shown in Table 1H, the aggregate EPFDdown limits shown in Table 2H shall apply to all antenna sizes greater than 60 cm in the frequency bands listed in Table 1H.

2 The earth station antenna reference patterns are to be used only for the calculation of interference from NGSO FSS systems into GSO FSS systems.

Table 2H - Single-Entry EPFDdown Limits Radiated By Non-GSO FSS Systems At Certain Latitudes

100% of the time EPFDdown dB(W/(m 2/40 kHz)) Latitude (North or South in degrees)
-160 0 <| Latitude | ≤57.5
-160 3.4 (57.5 − | Latitude |)/4 57.5 <| Latitude | ≤63.75
-165.3 63.75 ≤| Latitude |
Note to paragraph (h):

These limits relate to the equivalent power flux density, which would be obtained under free-space propagation conditions, for all conditions and for all methods of modulation.

(i) In the 10.7-11.7 GHz and 11.7-12.2 GHz bands, the additional operational equivalent power-flux density, in the space-to-Earth direction, (additional operational EPFDdown) at any point on the Earth's surface, produced by actual operational emissions from all co-frequency space stations of a non-geostationary-satellite orbit (NGSO) system operating in the Fixed-Satellite Service (FSS) shall not exceed the following operational limits for the given percentages of time:

Additional Operational Limits on the EPFDdown Radiated by Non-GSO FSS Systems Into 3 m and 10 m GSO FSS Earth Station Antennas

EPFDdown dB(W/(m 2/40 kHz)) Percentage of time during which EPFDdown may not be exceeded Receive GSO earth station
antenna diameter (m)
−182 99.9
−179 99.94
−176 99.97
−171 99.98
−168 99.984 3
−165 99.993
−163 99.999
−161.25 99.99975
−161.25 100
−185 99.97
−183 99.98
−179 99.99
−175 99.996
−171 99.998 10
−168 99.999
−166 99.9998
−166 100
Note to paragraph (i):

These limits relate to the equivalent power flux density, which is obtained under free-space propagation conditions, for all conditions and for all methods of modulation.

(j) In the 10.7-11.7 GHz and 11.7-12.2 GHz bands, the operational equivalent power-flux density, in the space-to-Earth direction, (operational EPFDdown) at any point on the Earth's surface, produced by actual operational emissions from the in-line co-frequency space station of a non-geostationary-satellite orbit (NGSO) system operating in the Fixed-Satellite Service (FSS) shall not exceed the following operational limits for 100% of the time:

Operational Limits to the EPFDdown Radiated by Non-GSO FSS Systems in Certain Frequency Bands 1

Frequency band (GHz) for International allocations EPFDdown dB(W/m 2) Percentage of time during which EPFDdown may not be exceeded Reference bandwidth (kHz) Receive GSO earth station antenna diameter 2 (m) Orbital inclination of GSO satelite (degrees)
Prior to 31 December 2005: 10.7-11.7 in all Regions; 11.7-12.2 in Regions 2; 12.2-12.5 in Region 3; and 12.5;-12.75 in Regions 1 and 3 −163
−166
−167.5
−169.5
100
40
3
6
9
≥18
≤2.5
Prior to 31 December 2005: 10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −160
−163
−164.5
−166.5
100
40
3
6
9
≥18
>2.5 and ≤4.5
From 31 December 2005: 10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −161.25
−164
−165.5
−167.5
100
40
3
6
9
≥18
≤2.5
From 31 December 2005: 10.7-11.7 in all Regions; 11.7-12.2 in Region 2; 12.2-12.5 in Region 3; and 12.5-12.75 in Regions 1 and 3 −158.25
−161
−162.5
−164.5
100
40
3
6
9
≥18
>2.5 and ≤4.5

1 The operational limits on the EPFDdown radiated by non-GSO FSS systems shall be the values given in Table 2G or this table, whichever are the more stringent.

2 For antenna diameters between the values given in this table, the limits are given by linear interpolation using a linear scale for EPFDdown in decibels and a logarithmic scale for antenna diameter in meters.

Note to paragraph (j):

These limits relate to the operational equivalent power flux-density which would be obtained under free-space propagation conditions, for all conditions, for all methods of modulation and for the specified inclined GSO FSS operations.

(k) In the 12.75-13.15 GHz, 13.2125-13.25 GHz and 13.75-14.5 GHz bands, the equivalent power flux-density, in the Earth-to-space direction, (EPFDup) produced at any point on the geostationary satellite orbit (GSO) by the emissions from all co-frequency earth stations in a non-geostationary satellite orbit Fixed-Satellite Service (NGSO FSS) system, for all conditions and for all methods of modulation, shall not exceed the following limits for the specified percentages of time limits:

Limits to the EPFDup Radiated by NGSO FSS Systems in Certain Frequency Bands

Frequency band (GHz) for International Allocations EPFDup dB(W/m 2) Percentage of time during which EPFDup may not be exceeded Reference bandwidth (kHz) Reference antenna beamwidth and reference radiation pattern 1
12.5-12.75; 12.75-13.25; 13.75-14.5 −160 100 40
ITU-R S.672-4,
Ls=−20

1 For the case of Ls = −10, the values a = 1.83 and b = 6.32 should be used in the equations in the Annex of Recommendation ITU-R S.672-4 for single-feed circular beams. In all cases of Ls, the parabolic main beam equation should start at zero.

Note to paragraph (k):

These limits relate to the uplink equivalent power flux density, which would be obtained under free-space propagation conditions, for all conditions and for all methods of modulation.

(l) In the 11.7-12.2 GHz and 12.5-12.75 GHz bands in Region 3, 11.7-12.5 GHz bands in Region 1, and 12.2-12.7 GHz band in Region 2, the single-entry equivalent power-flux density, in the space-to-Earth direction, (EPFDdown), at any point on the Earth's surface, produced by emissions from all co-frequency space stations of a single non-geostationary-satellite orbit (NGSO) system operating in the Fixed-Satellite Service (FSS) shall not exceed the following limits in Tables 1L and 2L for the given percentages of time:

Table 1L - Single-Entry EPFD down Limits for Protection of 30, 45, 60, 90, 120, 180, 240 and 300 CM GSO BSS Earth Station Antennas 1 2 3 5

Frequency band (GHz) for international
allocations
EPDF down dB(W/m 2) Percentage of time during which EPFDdown level may not be exceeded Reference bandwidth (kHz) Reference antenna diameter and reference radiation pattern 4
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −165.841
−165.541
−164.041
−158.6
−158.6
−158.33
−158.33
0
25
96
98.857
99.429
99.429
99.429
100
40 30 cm
Recommendation ITU-R
BO.1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −175.441
−172.441
−169.441
−164
−160.75
−160
−160
0
66
97.75
99.357
99.809
99.986
100
40 45 cm
Recommendation ITU-R
BO.1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −176.441
−173.191
−167.75
−162
−161
−160.2
−160
−160
0
97.8
99.371
99.886
99.943
99.971
99.997
100
40 60 cm
Recommendation ITU-R
BO. 1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −178.94
−178.44
−176.44
−171
−165.5
−163
−161
−160
−160
0
33
98
99.429
99.714
99.857
99.943
99.991
100
40 90 cm
Recommendation ITU-R
BO.1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −182.44
−180.69
−179.19
−178.44
−174.94
−173.75
−173
−169.5
−167.8
−164
−161.9
−161
−160.4
−160
0
90
98.9
98.9
99.5
99.68
99.68
99.85
99.915
99.94
99.97
99.99
99.998
100
40 120 cm
Recommendation ITU-R
BO.1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −184.941
−184.101
−181.691
−176.25
−163.25
−161.5
−160.35
−160
−160
0
33
98.5
99.571
99.946
99.974
99.993
99.999
100
40 180 cm 3
Recommendation ITU-R
BO.1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −187.441
−186.341
−183.441
−178
−161.4
−161.9
−160.5
−160
−160
0
33
99.25
99.786
99.957
99.983
99.994
99.999
100
40 240 cm 2
Recommendation ITU-R
BO.1443 Annex 1
11.7-12.5 in Region 1; 1.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −191.941
−189.441
−185.941
−180.5
−173
−167
−162
−160
−160
0
33
99.5
99.857
99.914
99.951
99.983
99.991
100
40 300 cm
Recommendation ITU-R
BO.1443 Annex 1

1 For BSS antenna diameters 180 cm, 240 cm and 300 cm, in addition to the single-entry limits shown in Table 1L, the limits in Table 2L shall also apply in the frequency band listed in Table 1L.

2 For 240 cm GSO BSS earth station antennas located in Alaska, communicating with GSO BSS satellites at the 91° W.L., 101° W.L., 110° W.L., 119° W.L. and 148° W.L. nominal orbital locations with elevation angles greater than 5°, −167 dB(W/(m 2/40 kHz)) single-entry 100% of the time operational EPFDdown limit also applies to receive antennas.

3 For 180 cm GSO BSS earth station antennas located in Hawaii communicating with GSO BSS satellites that are operational as of December 30, 1999 at the 110° W.L., 119° W.L. and 148° W.L. nominal orbital positions, −162.5 dB(W/(m 2/40 kHz)) single-entry 100% of the time operational EPFDdown limit also applies.

4 Under the section reference pattern of Annex 1 to Recommendation ITU-R BO.1443 shall be used only for the calculation of interference from non-GSO FSS systems into BSS systems.

5 For each reference antenna diameter, the limit consists of the complete curve on a plot which is linear in decibels for the EPFD levels and logarithmic for the time percentages, with straight line joining the data points.

Table 2L - Single-Entry EPFDdown Limits Radiated By Non-GSO FSS Systems At Certain Latitudes

100% of the time EPFDdown dB(W/(m 2/40 kHz)) Latitude (North or South in degrees)
−160.0 0 ≤| Latitude | ≤57.5
−160.0 3.4 (57.5 − | Latitude |)/4 57.5 ≤| Latitude | ≤63.75
−165.3 63.75 ≤| Latitude |
Note to paragraph (l):

These limits relate to the equivalent power flux density, which would be obtained under free-space propagation conditions, for all conditions and for all methods of modulation.

(m) In the 11.7-12.2 GHz and 12.5-12.75 GHz bands in Region 3, 11.7-12.5 GHz bands in Region 1, and 12.2-12.7 GHz band in Region 2, the aggregate equivalent power-flux density, in the space-to-Earth direction, (EPFDdown) at any point on the Earth's surface, produced by emissions from all co-frequency space stations of all non-geostationary-satellite orbit systems operating in the Fixed-Satellite Service (FSS) shall not exceed the following limits in Tables 1M and 2M for the given percentages of time:

Table 1M - Aggregate EPFDdown Limits for Protection of 30, 45, 60, 90, 120, 180, 240 and 300 cm GSO BSS Earth Station Antennas 1 2 3 5

Frequency band (GHz) for international allocations EPFDdown dB (W/m 2) Percentage of time during which EPFDdown level may not be exceeded Reference bandwidth (kHz) Reference antenna diameter, and reference radiation pattern 4
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −160.4
−160.1
−158.6
−158.6
−158.33
−158.33
0
25
96
98
98
100

40
30 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −170
−167
−164
−160.75
−160
−160
0
66
97.75
99.33
99.95
100

40
45 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −171
−168.75
−167.75
−162
−161
−160.2
−160
−160
0
90
97.8
99.6
99.8
99.9
99.99
100

40
60 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −173.75
−173
−171
−165.5
−163
−161
−160
−160
0
33
98
99.1
99.5
99.8
99.97
100

40
90 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −177
−175.25
−173.75
−173
−169.5
−167.8
−164
−161.9
−161
−160.4
−160
0
90
98.9
98.9
99.5
99.7
99.82
99.9
99.965
99.993
100

40
120 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −179.5
−178.66
−176.25
−163.25
−161.5
−160.35
−160
−160
0
33
98.5
99.81
99.91
99.975
99.995
100

40
180 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −182
−180.9
−178
−164.4
−161.9
−160.5
−160
−160
0
33
99.25
99.85
99.94
99.98
99.995
100

40
240 cm
Recommendation ITU-R
BO.1443
Annex 1.
11.7-12.5 in Region 1; 11.7-12.2 and 12.5-12.75 in Region 3; 12.2-12.7 in Region 2 −186.5
−184
−180.5
−173
−167
−162
−160
−160
0
33
99.5
99.7
99.83
99.94
99.97
100

40
300 cm
Recommendation ITU-R
BO.1443
Annex 1.

1 For BSS antenna diameters 180 cm, 240 cm and 300 cm, in addition to the aggregate limit shown in Table 1M, the limits in Table 2M shall also apply.

2 For 240 cm GSO BSS earth station antennas located in Alaska, communicating with GSO BSS satellites at the 91° W.L., 101° W.L., 110° W.L., 119° W.L. and 148° W.L. nominal orbital locations with elevation angles greater than 5°, −167 dB(W/(m 2/40 kHz)) aggregate 100% of the time operational EPFDdown limit also applies to receive antennas.

3 For 180 cm GSO BSS earth station antennas located in Hawaii communicating with GSO BSS satellites that are operational as of December 30, 1999 at the 110° W.L., 119° W.L. and 148° W.L. nominal orbital positions, −162.5 dB(W/(m 2/40 kHz)) aggregate 100% of the time operational EPFDdown limit also applies.

4 Under the section reference pattern of Annex 1 to Recommendation ITU-R BO.1443 shall be used only for the calculation of interference from non-GSO FSS systems into GSO BSS systems.

5 For each reference antenna diameter, the limit consists of the complete curve on a plot which is linear in decibels for the EPFD levels and logarithmic for the time percentages, with straight line joining the data points.

Table 2M - Aggregate EPFDdown Limits Radiated by Non-GSO FSS Systems At Certain Latitudes

00% of the time EPFDdown dB(W/(m 2/40 kHz)) Latitude (North or South in degrees)
160.0 0 ≤| Latitude | ≤57.5.
160.0 3.4 (57.5 − | Latitude |)/4 57.5 ≤| Latitude | ≤63.75.
165.3 63.75 ≤| Latitude |.
Note to paragraph (m):

These limits relate to the equivalent power flux density, which would be obtained under free-space propagation conditions, for all conditions and for all methods of modulation.

(n) The power-flux density at the Earth's surface produced by emissions from a space station in the Fixed-Satellite Service (space-to-Earth), for all conditions and for all methods of modulation, shall not exceed the limits given in Table N. These limits relate to the power flux-density which would be obtained under assumed free-space conditions.

Table N - Limits of Power-Flux Density From Space Stations in the Band 6700-7075 MHz

Frequency band Limit in dB (W/m 2) for angle of arrival (δ) above the horizontal plane Reference bandwidth
0°-5° 5°-25° 25°-90°
6700-6825 MHz −137 −137 0.5(δ−5) −127 1 MHz.
6825-7075 MHz −154
and
−154 0.5(δ−5)
and
−144
and
4 kHz.
−134 −134 0.5(δ−5) −124 1 MHz.

(o) In the band 12.2-12.7 GHz, for NGSO FSS space stations, the specified low-angle power flux-density at the Earth's surface produced by emissions from a space station shall not be exceeded into an operational MVDDS receiver:

(1) −158 dB(W/m 2) in any 4 kHz band for angles of arrival between 0 and 2 degrees above the horizontal plane; and

(2) −158 3.33(δ−2) dB(W/m 2) in any 4 kHz band for angles of arrival (δ) (in degrees) between 2 and 5 degrees above the horizontal plane.

Note to paragraph (o):

These limits relate to the power flux density, which would be obtained under assumed free-space propagation conditions.

(p) The power flux-density at the Earth's surface produced by emissions from a space station in either the Earth exploration-satellite service in the band 25.5-27 GHz or the inter-satellite service in the band 25.25-27.5 GHz for all conditions and for all methods of modulation shall not exceed the following values:

−115 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−115 0.5(−5) dB(W/m 2) in any 1 MHz band for angles of arrival between 5 and 25 degrees above the horizontal plane;

−105 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane.

These limits relate to the power flux-density which would be obtained under assumed free-space propagation conditions.

(q) In the band 37.5-40.0 GHz, the power flux-density at the Earth's surface produced by emissions from a geostationary space station for all methods of modulation shall not exceed the following values.

(1) This limit relates to the power flux-density which would be obtained under assumed free space conditions (that is, when no allowance is made for propogation impairments such as rain-fade):

−139 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−139 4/3 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 20 degrees above the horizontal plane; and

−119 0.4 (δ−20) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 20 and 25 degrees above the horizontal plane;

−117 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane;

(2) This limit relates to the maximum power flux-density which would be obtained anywhere on the surface of the Earth during periods when FSS system raises power to compensate for rain-fade conditions at the FSS Earth station:

−127 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−127 4/3 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 20 degrees above the horizontal plane; and

−107 0.4 (δ−20) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 20 and 25 degrees above the horizontal plane;

−105 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane.

Note to paragraph (q):

The conditions under which satellites may exceed the power flux-density limits for normal free space propagation described in paragraph (p)(1) to compensate for the effects of rain fading are under study and have therefore not yet been defined. Such conditions and the extent to which these limits can be exceeded will be the subject of a further rulemaking by the Commission on the satellite service rules.

(r) In the band 37.5-40.0 GHz, the power flux-density at the Earth's surface produced by emissions from a non-geostationary space station for all methods of modulation shall not exceed the following values:

(1) This limit relates to the power flux-density which would be obtained under assumed free space conditions (that is, when no allowance is made for propogation impairments such as rain-fade):

−132 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−132 0.75 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 25 degrees above the horizontal plane; and

−117 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane;

(2) This limit relates to the maximum power flux-density which would be obtained anywhere on the surface of the Earth during periods when FSS system raises power to compensate for rain-fade conditions at the FSS Earth station:

−120 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−120 0.75 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 25 degrees above the horizontal plane; and

−105 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane.

Note to paragraph (r):

The conditions under which satellites may exceed these power flux-density limits for normal free space propagation described in paragraph (q)(1) to compensate for the effects of rain fading are under study and have therefore not yet been defined. Such conditions and the extent to which these limits can be exceeded will be the subject of a further rulemaking by the Commission on the satellite service rules.

(s) In the 40.0-40.5 GHz band, the power flux density at the Earth's surface produced by emissions from a space station for all conditions and for all methods of modulation shall not exceed the following values:

−115 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−115 0.5 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 25 degrees above the horizontal plane; and

−105 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane;

Note to paragraph (s):

These limits relate to the power flux-density that would be obtained under assumed free-space propagation conditions.

(t) In the band 40.5-42.0 GHz, the power flux density at the Earth's surface produced by emissions from a non-geostationary space station for all conditions and for all methods of modulation shall not exceed the following values:

−115 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−115 0.5 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 25 degrees above the horizontal plane; and

−105 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane;

Note to paragraph (t):

These limits relate to the power flux density that would be obtained under assumed free-space propagation conditions.

(u) In the band 40.5-42.0 GHz, the power flux-density at the Earth's surface produced by emissions from a geostationary space station for all conditions and for all methods of modulation shall not exceed the following values:

−120 dB(W/m 2) in any 1 MHz band for angles of arrival between 0 and 5 degrees above the horizontal plane;

−120 (δ−5) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 5 and 15 degrees above the horizontal plane;

−110 0.5 (δ−15) dB(W/m 2) in any 1 MHz band for angles of arrival δ (in degrees) between 15 and 25 degrees above the horizontal plane; and

−105 dB(W/m 2) in any 1 MHz band for angles of arrival between 25 and 90 degrees above the horizontal plane;

Note to paragraph (u):

These limits relate to the power flux-density that would be obtained under assumed free-space propagation conditions.

(v) In the band 2496-2500 MHz, the power flux-density at the Earth's surface produced by emissions from non-geostationary space stations for all conditions and all methods of modulation shall not exceed the following values (these values are obtained under assumed free-space propagation conditions):

(1) −144 dB (W/m^2) in 4 kHz for all angles of arrival between 0 and 5 degrees above the horizontal plane; −144 dB (W/m^2) 0.65(δ −5) in 4 kHz for all angles of arrival between 5 and 25 degrees above the horizontal plane; and

−131 dB (W/m^2) in 4 kHz and for all angles of arrival between 25 and 90 degrees above the horizontal plane.

(2) −126 dB (W/m^2) in 1 MHz for all angles of arrival between 0 and 5 degrees above the horizontal plane; −126 dB (W/m^2) 0.65(δ −5) in 1 MHz for all angles of arrival between 5 and 25 degrees above the horizontal plane; and

−113 dB (W/m^2) in 1 MHz and for all angles of arrival between 25 and 90 degrees above the horizontal plane.

(w) The power flux density at the Earth's surface produced by emissions from a 17/24 GHz BSS space station operating in the 17.3-17.7 GHz band for all conditions and all methods of modulation must not exceed the regional power flux density levels prescribed in paragraphs (w)(1) through (4) of this section.

(1) In the region of the contiguous United States, located south of 38° North Latitude and east of 100 West Longitude: −115 dBW/m 2/MHz.

(2) In the region of the contiguous United States, located north of 38° North Latitude and east of 100° West Longitude: −118 dBW/m 2/MHz.

(3) In the region of the contiguous United States, located west of 100 West Longitude: −121 dBW/m 2/MHz.

(4) For all regions outside of the contiguous United States including Alaska and Hawaii: −115 dBW/m 2/MHz.

Note to paragraph (w):

These limits pertain to the power flux-density that would be obtained under assumed free-space propagation conditions.

[48 FR 40255, Sept. 6, 1983]
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United States Code

Title 47 published on 2015-10-01

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  • 2015-11-06; vol. 80 # 215 - Friday, November 6, 2015
    1. 80 FR 68815 - Review of Foreign Ownership Policies for Broadcast, Common Carrier and Aeronautical Radio Licensees
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      FEDERAL COMMUNICATIONS COMMISSION
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      Submit comments on or before December 21, 2015, and replies on or before January 20, 2016. The NPRM contains potential information collection requirements subject to the PRA, Public Law 104-13. OMB, the general public, and other Federal agencies are invited to comment on the potential new and modified information collection requirements contained in this NPRM. If the information collection requirements are adopted, the Commission will submit the appropriate documents to OMB for review under Section 3507(d) of the PRA. OMB, the general public, and other Federal agencies will again be invited to comment on the new and modified information collection requirements adopted by the Commission.
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