Attachment RF Statement

This document pretains to SES-MOD-20110902-01021 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2011090201021_914479

Antenna RF Radiation Hazard Study for an AVL -1201K, Mobile Based Earth Station System A study was performed, analyzing the non-ionizing radiation levels for a 1.2 meter mobile earth station system. The guidelines of the FCC OET Bulletin, No. 65, Edition 97-01 were used for compliance calculations. The Maximum Permissible Exposure (MPE) guidelines were calculated for both General Population/Uncontrolled and Occupational/Controlled exposure levels. The calculations were performed as follows: Appendix A – Earth Station Criteria Appendix B – Calculations for Antenna RF Radiation Hazard The applicant is in conformance with the FCC guidelines, with the proposed procedures, as outlined in the OET Bulletin No. 65, Edition 97-01, Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields, August 1997. The applicant proposes to maintain compliance with the MPE for Controlled and Uncontrolled areas in the following manner as shown under NOTE. NOTE: The emitting antenna is located on a mobile truck, with the lower edge of the antenna raised 3.5 meters above ground. The general public will not have access within 0.6 meters of the emitting antenna. Since 0.6 meters is removed from the edge of the antenna, the RF levels are reduced by a factor of 100 or 20 dB. None of the areas exceeding the MPE levels will be accessible by the general public. Radiation Hazard signs will be posted while this earth station is in operation. The applicant will ensure that no buildings or other obstacles are in the path or in the areas that exceed the MPE levels. The earth station’s authorized operational personnel will not have access to the areas that exceed the MPE levels while the earth station is in operation. The transmitter will be turned off during antenna maintenance. Ted Hand, CPBE, 8-VSB, DRB, AMD Director of Engineering Cox Media Group – Charlotte

Appendix A Earth Station Criteria Data Entry: Dant Antenna main relector diamater 1.2 m Dfeed(sub) Feed flange (or subreflector) diameter 10.1 cm Rf transmit frequency 14.250 GHz Pfeed Max power into atnenna feed-flange 119.40 W Gant Main-beam gain of ant at xmtr frequency 43.5 dBi Gant (Numeric) 22387.21 Antenna aperture efficiency 0.70 Antenna main reflector surface area 1.13 m/sq2 Feed flange (or subreflector) surface area 80.12 cm2 Wavelength of the RF transmit frequency 0.021 m Distance to beginning of far-field region 41.07 m Distance to extent of near-field region 17.11 m EIRP 64.27 dBW EIRP 2,673,033.04 W

Appendix B Calculations for Antenna RF Radiation Hazard 1. Near Field: Rnear = extent of the near-field (in meters) Dant = diameter of the antenna main reflector (in Meters) 1.20 m λ = wavelength of the RF transmit frequency (in meters) 0.02 m Rnear = (Dant)2/(4λ) Rnear = 17.11 m Snear = maximum on-axis power density within near field (mw/cm2) η = antenna aperture efficiency 0.70 Pfeed = maximum power into antenna feed flange (in watts) 119.40 W Dant = diameter of the antenna main reflector (in Meters) 1.20 m π = PI 3.14 Snear = {(16ηPfeed)/[π(Dant)2]}/10 Snear = 29.44 (mw/cm2) 2. Far Field: Rfar = distance to beginning of far field (in meters) Dant = diameter of the antenna main reflector (in Meters) 1.20 m λ = wavelength of the RF transmit frequency (in meters) 0.02 m Rfar = [0.6(Dant)2]/λ Rfar = 41.07 m Sfar = maximum on-axis power density in the far field (mw/cm2) Pfeed = maximum power into antenna feed flange (in watts) 119.40 W Gant = antenna main beam gain at RF xmt frequency (numeric) 22387.21 Rfar = distance to beginning of far field (in meters) 41.07 m Sfar = [(PfeedGant)/4π(Rfar)2]/10 Sfar = 12.61 (mw/cm2) 3. Antenna Transition Region Power Density Calculation Str = maximum on-axis power density in the transition region (mw/cm2) Snear = maximum on-axis power density within near field (mw/cm2) Rnear = extent of the near-field (in meters) R = distance within transition region between near field and far field regions. R = Rfar-Rnear R = 17.21 m Str = SnearRnear/R Str = 29.27 (mw/cm2) Str ? Snear Str = OK

4. Antenna Feed-Flange (or Subreflector) Power Density Calculation Sfeed (sub) = max pwr density at ant feed-flange or subreflector surface (mw/cm2) Pfeed = maximum power into antenna feed flange (in watts) 119.40 W Dfeed (sub) = diameter of the antenna feed-flange or subreflector (cm) 0.10 cm Sfeed (sub) = 1000{[2(Pfeed)]/{[π(Dfeed (sub))2]/4}} Sfeed = 5961.17 (mw/cm2) 5. Antenna Main Reflector Power Density Calculation Sant = maximum power density in the antenna main reflector region (mw/cm2) Pfeed = maximum power into antenna feed flange (in watts) 119.40 W Dant = diameter of the antenna main reflector (in Meters) 1.20 m Sant = {[2(Pfeed)]/{[π(Dant)2]/4}}/10 Sant = 42.23 (mw/cm2) 6. Power Density Calculation between the Antenna Main Reflector and the Ground Sground = maximum power density between the ant main relector and ground (mw/cm2) Pfeed = maximum power into antenna feed flange (in watts) 119.40 W Dant = diameter of the antenna main reflector (in Meters) 1.20 m Sgrouind = {Pfeed/{[π(Dant)2]/4}}/10 Sground = 10.56 (mw/cm2)



Document Created: 2011-09-01 15:15:23
Document Modified: 2011-09-01 15:15:23
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