Sec. 25.208  Power flux density limits.

    (a) In the band 3700-4200 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/m2) in any 4 kHz band for angles of arrival between 
0 and 5 degrees above the horizontal plane;
-152+(-5)/2 dB(W/m2) in any 4 kHz band for angles of 
arrival  (in degrees) between 5 and 25 degrees above the 
horizontal plane; and
-142 dB(W/m2) 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, 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:

-150 dB(W/m2) in any 4 kHz band for angles of arrival between 
0 and 5 degrees above the horizontal plane;
-150+(-5)/2 dB(W/m2) in any 4 kHz band for angles of 
arrival  (in degrees) between 5 and 25 degrees above the 
horizontal plane; and
-140 dB(W/m2) 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.
    (c) In the 17.7-19.7 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 
and 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 (d-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.
[ 48 FR 40255 , Sept. 6, 1983, as amended at  52 FR 45636 , Dec. 1, 1987;  59 FR 53329 , Oct. 21, 1994]