47 C.F.R. § 101.1333
Interference protection criteria.
Cite as 47 C.F.R. § 101.1333 (2026)
(a)
Frequency coordination.
All EA licensees are required to coordinate their frequency usage with co-channel adjacent area licensees and all other affected parties.
(b) EA licensees are prohibited from exceeding a signal strength of 40 dBµV/m at their service area boundaries, unless a higher signal strength is agreed to by all affected co-channel, adjacent area licensees.
(c) EA licensees are prohibited from exceeding a signal strength of 40 dBµV/m at incumbent licensees' 40.2 kilometer (25-mile) radius composite contour specified in § 101.1331(c).
(d) In general, licensees shall comply with the appropriate coordination agreements between the United States and Canada and the United States and Mexico concerning cross-border sharing and use of the applicable MAS frequencies.
(1)
Canada—932.0-932.25 MHz and 941.0-941.25 MHz.
(i) Within Lines A, B, C, and D, as defined in § 1.928(e) of this chapter, along the U.S./Canada border, U.S. stations operating in the 932.0-932.25 MHz and 941.0-941.25 MHz bands are on a secondary basis and may operate provided that they shall not transmit a power flux density (PFD) at the border greater than −100 dBW/m
2
nor −94 dBW/m
2
, respectively. The U.S. has full use of the frequencies in these regions up to the border in the bands 932.25-932.50 MHz and 941.25-941.50 MHz, and Canadian stations may operate on a secondary basis provided they do not exceed the respective PFDs shown above. PFD can be determined using the following formula: PFD (dBW/m
2
) = 10 log [EIRP/4π(D
2
], where EIRP is in watts, D is in meters, and the power is relative to an isotropic radiator. The technical parameters are also limited by tables 1 and 2:
Table 1—Maximum Radiated Power
Class of station
Band MHz
Maximum EIRP
Maximum ERP
1
Watts
dBW
Watts
dBW
Master
941.0-941.5
1000
30
600
27.8
Fixed Remote and Master
932.0-932.5
50
17
30
14.8
1
Where ERP = EIRP/1.64.>
(ii) Maximum antenna height above average terrain for master stations operating at a maximum power shall not exceed 150 meters. Above 150 meters, the power of master stations shall be in accordance with following table:
Table 2—Antenna Height—Power Reduction Table
Antenna height above average terrain (meters)
EIRP
ERP
Watts
dBW
Watts
dBW
Above 305
200
23
120
20.8
Above 275 to 305
250
24
150
21.8
Above 245 to 275
315
25
190
22.8
Above 215 to 245
400
26
240
23.8
Above 180 to 215
500
27
300
24.8
Above 150 to 180
630
28
380
25.8
Note to Table 2:
This information is from the
Arrangement between the Federal Communications Commission and the National Telecommunications and Information Administration of the United States of America, and Industry Canada concerning the use of the bands 932 to 935 MHz and 941 to 944 MHz along the United States-Canada border
signed in 1994. This agreement also lists grandfathered stations that must be protected.
(2)
Canada—928-929 MHz and 952-960 MHz.
Between Lines A and B and between Lines C and D, as defined in § 1.928(e) of this chapter, along the U.S./Canada border, U.S. stations operating in the 928.50-928.75 MHz and 952.50-952.75 MHz bands are on an unprotected basis and may operate provided that they shall not transmit a power flux density (PFD) at or beyond the border greater than −100 dBW/m
2
. The U.S. has full use of the frequencies in these regions up to the border in the bands 928.25-928.50 MHz and 952.25-952.50 MHz, and Canadian stations may operate on an unprotected basis provided they do not exceed the PFD above. Frequencies in the bands 928.00-928.25 MHz, 928.75-929.00 MHz, 952.00-952.25 MHz, and 952.75-952.85 MHz are available for use on a coordinated, first-in-time, shared basis subject to protecting grandfathered stations. New stations must provide a minimum of 145 km (90 miles) separation or alternatively limit the actual PFD of the proposed station to −100 dBW/m
2
, at the existing co-channel master stations of the other country, or as mutually agreed upon on a case-by-case basis. Coordination is not required if the PFD at the border is lower than −100 dBW/m
2
. The technical criteria are also limited by the following:
Maximum EIRP for master stations in the MHz band: 1000 watts (30 dBW) 952-953
Maximum EIRP for fixed remote stations or stations in the 928-929 MHz band: 50 watts (17 dBW) master
Maximum EIRP for mobile master stations: 25 watts (14 dBW)
Maximum antenna height above average master or control stations: 152 m at 1000 watts terrain for EIRP, power derated in accordance with the following table:
Antenna height above
average terrain (m)
EIRP
Watts
dBm
Above 305
200
53
Above 275 to 305
250
54
Above 244 to 274
315
55
Above 214 to 243
400
56
Above 183 to 213
500
57
Above 153 to 182
630
58
Below 152
1000
60
Note to table in paragraph (
d
)(2):
This information is from the
Arrangement between the Department of Communications of Canada and the Federal Communications Commission of the United States of America Concerning the Use of the Bands 928 to 929 MHz and 952 to 953 MHz along the United States-Canada Border
signed in 1991. This agreement also lists grandfathered stations that must be protected.
(3)
Mexico.
Within 113 kilometers of the U.S./Mexico border, U.S. stations operating in the 932.0-932.25 MHz and 941.0-941.25 MHz bands are on a secondary basis (non-interference to Mexican primary licensees) and may operate provided that they shall not transmit a power flux density (PFD) at or beyond the border greater than −100 dBW/m
2
. Upon notification from the Commission, U.S. licensees must take proper measures to eliminate any harmful interference caused to Mexican primary assignments. The U.S. has full use of the frequencies in these regions up to the border in the bands 932.25-932.50 MHz and 941.25-941.50 MHz, and Mexican stations may operate on a secondary basis (non-interference to U.S. primary licensees) provided they do not exceed the PFD shown above. Stations using the 932-932.5 MHz band shall be limited to the maximum effective isotropic radiated power of 50 watts (17 dBW). Stations using the 941-941.5 MHz band shall meet the limits in the following table:
Antenna height above
average mean sea level (meters)
EIRP
Watts
dBW
Above 305
200
23
Above 274 to 305
250
24
Above 243 to 274
315
25
Above 213 to 243
400
26
Above 182 to 213
500
27
Above 152 to 182
630
28
Up to 152
1000
30
Note to table in paragraph (
d
)(3):
This information is from the
Agreement between the Government of the United States of America and the Government of the United Mexican States Concerning the Allocation and Use of Frequency Bands by Terrestrial Non-Broadcasting Radiocommunication Services Along the Common Border, Protocol #6 Concerning the Allotment and Use of Channels in the 932-932.5 and 941-941.5 MHz Bands for Fixed Point-to-Multipoint Services Along the Common Border
signed in 1994.
[65 FR 17450, Apr. 3, 2000, as amended at 68 FR 4961, Jan. 31, 2003]
- Cross-references to the CFR
- 1.928101.1331