Code of Federal Regulations (alpha)

CFR /  Title 47  /  Part 25  /  Sec. 25.218 Off-axis EIRP density envelopes for FSS earth stations

(a) This section applies to all applications for Fixed-Satellite Service earth stations transmitting to geostationary space stations in the C band, Ku band, or extended Ku band, except for:

(1) ESV, VMES, and ESAA applications, and

(2) Analog video earth station applications.

(b) Earth station applications subject to this section are eligible for routine processing if they meet the applicable off-axis EIRP density envelope set forth in this section below. The terms ``conventional Ku band'' and ``extended Ku band are defined in Sec. 25.103.

(c) C-band analog earth station operations. (1) In the plane of the geostationary satellite orbit as it appears at the particular earth station location: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------29.5-25log10[thetas]............... dBW/4 kHz............. For................... 1.5[deg] <=[thetas]

<=7[deg]8.5................................ dBW/4 kHz............. For................... 7[deg] <[thetas] <=9.2[deg]32.5-25log10[thetas]............... dBW/4 kHz............. For................... 9.2[deg] <[thetas]

<=48[deg]-9.5............................... dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is the angle in degrees from the line connecting the focal point of the antenna to the target satellite, and the geostationary orbit plane is determined by the focal point of the antenna and the line tangent to the arc of the geostationary satellite orbit at the position of the target satellite. For the purposes of this section, the peak EIRP density of an individual sidelobe may not exceed the envelope defined above for [thetas] between 1.5[deg] and 7.0[deg]. For [thetas] greater than 7.0[deg], the envelope may be exceeded by no more than 10% of the sidelobes, provided no individual sidelobe exceeds the envelope given above by more than 3 dB.

(2) In all other directions, or in the plane of the horizon including any out-of-plane potential terrestrial interference paths: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------32.5-25log10[thetas]............... dBW/4 kHz............. For................... 3[deg] <=[thetas] <=48[deg]-9.5............................... dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is the angle in degrees from the line connecting the focal point of the antenna to the target satellite, within any plane that includes that line, with the exception of the plane determined by the focal point of the antenna and the line tangent to the arc of the geostationary satellite orbit at the position of the target satellite. For the purposes of this section, the envelope may be exceeded by no more than 10% of the sidelobes provided no individual sidelobe exceeds the envelope given above by more than 6 dB. The region of the main reflector spillover energy is to be interpreted as a single lobe and shall not exceed the envelope by more than 6 dB.

(d) C-band digital earth station operations. (1) In the plane of the geostationary satellite orbit as it appears at the particular earth station location: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------26.3-10log10(N)-25log10[thetas].... dBW/4 kHz............. For................... 1.5[deg] <=[thetas]

<=7[deg]5.3-10log10(N)..................... dBW/4 kHz............. For................... 7[deg] <[thetas] <=9.2[deg]29.3 -10log10(N)-25log10[thetas]... dBW/4 kHz............. For................... 9.2[deg] <[thetas]

<=48[deg]-12.7-10log10(N)................... dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] and the plane of the geostationary satellite orbit are defined in paragraph (c)(1) of this section, and N is defined below. For the purposes of this section, the peak EIRP density of an individual sidelobe may not exceed the envelope defined above for [thetas] between 1.5[deg] and 7.0[deg]. For [thetas] greater than 7.0[deg], the envelope may be exceeded by no more than 10% of the sidelobes, provided no individual sidelobe exceeds the envelope given above by more than 3 dB. For digital SCPC using frequency division multiple access (FDMA) or time division multiple access (TDMA) technique, N is equal to one. For digital SCPC using code division multiple access (CDMA) technique, N is the maximum number of co-frequency simultaneously transmitting earth stations in the same satellite receiving beam.

(2) In all other directions, or in the plane of the horizon including any out-of-plane potential terrestrial interference paths: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------29.3-10log10(N)-25log10[thetas].... dBW/4 kHz............. For................... 3[deg] <=[thetas] <=48[deg]-12.7-10log10(N)................... dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is defined in paragraph (c)(2) of this section, and N is defined in paragraph (d)(1) of this section. For the purposes of this section, the envelope may be exceeded by no more than 10% of the sidelobes provided no individual sidelobe exceeds the envelope given above by more than 6 dB. The region of the main reflector spillover energy is to be interpreted as a single lobe and shall not exceed the envelope by more than 6 dB.

(e) Conventional Ku-band analog earth station operations. (1) In the plane of the geostationary satellite orbit as it appears at the particular earth station location: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------21-25log10[thetas]................. dBW/4 kHz............. For................... 1.5[deg] <=[thetas]

<=7[deg]0.................................. dBW/4 kHz............. For................... 7[deg] <[thetas] <=9.2[deg]24-25log10[thetas]................. dBW/4 kHz............. For................... 9.2[deg] <[thetas]

<=48[deg]-18................................ dBW/4 kHz............. For................... 48[deg] <[thetas] <=85[deg]-8................................. dBW/4 kHz............. For................... 85[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] and the plane of the geostationary satellite are defined in paragraph (c)(1) of this section. For the purposes of this section, the peak EIRP density of an individual sidelobe may not exceed the envelope defined above for [thetas] between 1.5[deg] and 7.0[deg]. For [thetas] greater than 7.0[deg], the envelope may be exceeded by no more than 10% of the sidelobes, provided no individual sidelobe exceeds the envelope given above by more than 3 dB.

(2) In all other directions, or in the plane of the horizon including any out-of-plane potential terrestrial interference paths: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------24-25log10[thetas]................. dBW/4 kHz............. For................... 3[deg] <=[thetas] <=48[deg]-18................................ dBW/4 kHz............. For................... 48[deg] <[thetas] <=85[deg]-8................................. dBW/4 kHz............. For................... 85[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is defined in paragraph (c)(2) of this section. For the purposes of this section, the envelope may be exceeded by no more than 10% of the sidelobes provided no individual sidelobe exceeds the envelope given above by more than 6 dB. The region of the main reflector spillover energy is to be interpreted as a single lobe and shall not exceed the envelope by more than 6 dB.

(f) Conventional Ku-band digital earth station operations. (1) In the plane of the geostationary satellite orbit as it appears at the particular earth station location: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------15-10log10(N)-25log10[thetas]...... dBW/4 kHz............. For................... 1.5[deg] <=[thetas]

<=7[deg]-6-10log10(N)...................... dBW/4 kHz............. For................... 7[deg] <[thetas] <=9.2[deg]18-10log10(N)-25log10[thetas]...... dBW/4 kHz............. For................... 9.2[deg] <[thetas]

<=48[deg]-24-10log10(N)..................... dBW/4 kHz............. For................... 48[deg] <[thetas] <=85[deg]-14-10log10(N)..................... dBW/4 kHz............. For................... 85[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] and the plane of the geostationary satellite orbit are defined in paragraph (c)(1) of this section, and N is defined below. For the purposes of this section, the peak EIRP density of an individual sidelobe may not exceed the envelope defined above for [thetas] between 1.5[deg] and 7.0[deg]. For [thetas] greater than 7.0[deg], the envelope may be exceeded by no more than 10% of the sidelobes, provided no individual sidelobe exceeds the envelope given above by more than 3 dB. For digital SCPC using frequency division multiple access (FDMA) or time division multiple access (TDMA) technique, N is equal to one. For digital SCPC using code division multiple access (CDMA) technique, N is the maximum number of co-frequency simultaneously transmitting earth stations in the same satellite receiving beam.

(2) In all other directions, or in the plane of the horizon including any out-of-plane potential terrestrial interference paths: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------18-10log10(N)-25log10[thetas]...... dBW/4 kHz............. For................... 3[deg] <=[thetas] <=48[deg]-24-10log10(N)..................... dBW/4 kHz............. For................... 48[deg] <[thetas] <=85[deg]-14-10log10(N)..................... dBW/4 kHz............. For................... 85[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is defined in paragraph (c)(2) of this section, and N is defined in paragraph (f)(1) of this section. For the purposes of this section, the envelope may be exceeded by no more than 10% of the sidelobes provided no individual sidelobe exceeds the envelope given above by more than 6 dB. The region of the main reflector spillover energy is to be interpreted as a single lobe and shall not exceed the envelope by more than 6 dB.

(g) Extended Ku-band analog earth station operations. (1) In the plane of the geostationary satellite orbit as it appears at the particular earth station location: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------21-25log10[thetas]................. dBW/4 kHz............. For................... 1.5[deg] <=[thetas]

<=7[deg]0.................................. dBW/4 kHz............. For................... 7[deg] <[thetas] <=9.2[deg]24-25log10[thetas]................. dBW/4 kHz............. For................... 9.2[deg] <[thetas]

<=48[deg]-18................................ dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] and the plane of the geostationary satellite orbit are defined in paragraph (c)(1) of this section. For the purposes of this section, the peak EIRP density of an individual sidelobe may not exceed the envelope defined above for [thetas] between 1.5[deg] and 7.0[deg]. For [thetas] greater than 7.0[deg], the envelope may be exceeded by no more than 10% of the sidelobes, provided no individual sidelobe exceeds the envelope given above by more than 3 dB.

(2) In all other directions, or in the plane of the horizon including any out-of-plane potential terrestrial interference paths: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------24-25log10[thetas]................. dBW/4 kHz............. For................... 3[deg] <=[thetas] <=48[deg]

-18................................ dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is defined in paragraph (c)(2) of this section. For the purposes of this section, the envelope may be exceeded by no more than 10% of the sidelobes provided no individual sidelobe exceeds the envelope given above by more than 6 dB. The region of the main reflector spillover energy is to be interpreted as a single lobe and shall not exceed the envelope by more than 6 dB.

(h) Extended Ku-band digital earth station operations. (1) In the plane of the geostationary satellite orbit as it appears at the particular earth station location: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------15-10log10(N)-25log10[thetas]...... dBW/4 kHz............. For................... 1.5[deg] <=[thetas]

<=7[deg]-6-10log10(N)...................... dBW/4 kHz............. For................... 7[deg] <[thetas] <=9.2[deg]18-10log10(N)-25log10[thetas]...... dBW/4 kHz............. For................... 9.2[deg] <[thetas]

<=48[deg]-24-10log10(N)..................... dBW/4 kHz............. For................... 48[deg] <[thetas]

<=180[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] and the plane of the geostationary satellite orbit are defined in paragraph (c)(1) of this section, and N is defined below. For the purposes of this section, the peak EIRP density of an individual sidelobe may not exceed the envelope defined above for [thetas] between 1.5[deg] and 7.0[deg]. For [thetas] greater than 7.0[deg], the envelope may be exceeded by no more than 10% of the sidelobes, provided no individual sidelobe exceeds the envelope given above by more than 3 dB. For digital SCPC using frequency division multiple access (FDMA) or time division multiple access (TDMA) technique, N is equal to one. For digital SCPC using code division multiple access (CDMA) technique, N is the maximum number of co-frequency simultaneously transmitting earth stations in the same satellite receiving beam.

(2) In all other directions, or in the plane of the horizon including any out-of-plane potential terrestrial interference paths: ----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------18-10log10(N)-25log10[thetas]...... dBW/4 kHz............. For................... 3[deg] <=[thetas] <=48[deg]-24-10log10(N)..................... dBW/4 kHz............. For................... 48[deg] <[thetas] <=85[deg]---------------------------------------------------------------------------------------------------------------- where [thetas] is defined in paragraph (c)(2) of this section and N is defined in paragraph (h)(1) of this section. For the purposes of this section, the envelope may be exceeded by no more than 10% of the sidelobes provided no individual sidelobe exceeds the envelope given above by more than 6 dB. The region of the main reflector spillover energy is to be interpreted as a single lobe and shall not exceed the envelope by more than 6 dB. [73 FR 70902, Nov. 24, 2008, as amended at 74 FR 57099, Nov. 4, 2009; 78 FR 8429, Feb. 6, 2013; 78 FR 14927, Mar. 8, 2013; 79 FR 8324, Feb. 12, 2014]

Effective Date Note: At 74 FR 9962, Mar. 9, 2009, Sec. 25.218, which contains information collection and recordkeeping requirements, became effective with approval by the Office of Management and Budget for a period of 3 years. Sec. 25.219 [Reserved]