Attachment Exhibit C

This document pretains to SES-STA-20071120-01600 for Special Temporal Authority on a Satellite Earth Station filing.

IBFS_SESSTA2007112001600_606614

        EXHIBIT C

RADIATION HAZARD REPORT




  INTELSAT NORTH AMERICA LLC
   RASCom—1 LEOP STA REQUEST
     EARTH STATION E040125


Radiation Hazard Report                                                               Page 1 of 6




                                               EXHIBIT C
     Analysis of Non—lonizing Radiation for a 11.0—Meter Earth
                          Station System
This report analyzes the non—jonizing radiation levels for a 11.0—meter earth station system. The
analysis and calculations performed in this report comply with the methods described in the FCC
Office of Engineering and Technology Bulletin, No. 65 first published in 1985 and revised in 1997
in Edition 97—01. The radiation safety limits used in the analysis are in conformance with the FCC
R&O 96—326. Bulletin No. 65 and the FCC R&O specifies that there are two separate tiers of
exposure limits that are dependant on the situation in which the exposure takes place and/or the
status of the individuals who are subject to the exposure. The Maximum Permissible Exposure
(MPE) limits for persons in a General Population/Uncontrolled environment are shown in Table 1.
The General Population/Uncontrolled MPE is a function of transmit frequency and is for an
exposure period of thirty minutes or less. The MPE limits for persons in an
Occupational/Controlled environment are shown in Table 2. The Occupational MPE is a function of
transmit frequency and is for an exposure period of six minutes or less. The purpose of the
analysis described in this report is to determine the power flux density levels of the earth station in
the far—field, near—fleld, transition region, between the subreflector or feed and main reflector
surface, at the main reflector surface, and between the antenna edge and the ground and to
compare these levels to the specified MPEs.                   —

               Table 1. Limits for General Population/Uncontrolled Exposure (MPE)
                  Frequency Range (MHz)                Power Density (mW/icm*)
                            30—300                                  0.2
                           300—1500            :         Frequency (MHz)*(0.8/1200)
                         1500—100,000                               1.0

                    Table 2. Limits for Occupational/Controlled Exposure (MPE)
                 _ Frequency Range (MHz)               Power Density (mW/cm")
                             30—300                                  1.0
                            300—1500                     Frequency (MHz)*(4.0/1200)
                          1500—100,000                               5.0

          Table 3. Formulaé and Parameters Used for Determining Power Flux Densities
     Parameter                     Symbol                 Formula            Value            Units
     Antenna Diameter                 D            —        Input             11.0            m
     Anterina Surface Area          Asurface              1 D/ 4              95.03           m*
     Subreflector Diameter            Der                   Input             121.9           om
     Area of Subreflector             Asr                 x Ds °/4          11670.71          ocm
     Frequency                         F                    Input             6182            MHz
     Wavelength                        A                   300 / F          0.048528          m
     Transmit Power                    P                    Input            2250.00          W


Radiation Hazard Report                                                                Page 2 of 6
     Antenna Gain (dBi}                 Geg            Input                    55.5                dBi
     Antenna Gain (factor)              G             1 pcesn0             354813.4                 n/a
      Pi                                Ei           Constant             3.1415927                 n/a
     Antenna Efficiency                 n            GM(RD)                     0.70        _       n/a



1.         Far Field Distance Calculation

The distance to the beginning of the far fiéld can be determined from the following equation:

     Distance to the Far Field Region                            Ry =0.60 D@/ x                           (1)
                                                 ‘                  = 1496.0 m

The maximum main beam power d‘ensity in the far field can be determined from thek following
equation:

     On—Axis Power Density in the Far Field                      Sy =GP/ (41Ry")                          (2)
                                                                    = 28.385 W/m*
                                                                    = 2.838 mW/cm"

2.         Near Field Calculation

Power flux density is considered to be at a maximum value throughout the entire length of the
defined Near Field region. The region is contained within a cylindrical volume having the same
diameter as the antenna. Past the boundary of the Near Field region, the power density from the
antenna decreases linearly with respect to increasing distance.

The distance to the end of the Near Field can be determined from the following equation:

     Extent of the Near Field                                    Ry = D/ (42)          >                  (3)
                             §      ‘                               = 623.4 m                   ‘

The maximum power densityin the Near Field can be determined from the following equation:

     Near Field Power Density                                    S =16.0 n P/(1 D)                        (4)
                                                                    = 66.262 W/im*
                                                                    = 6.626 mW/cm*

3.         Transition Region Calculation

The Transition region is located between the Near and Far Field regions. The power density
begins to decrease linearly with increasing distance in the Transition region. While the power
density decreases inversely with distance in the Transition region, the power density decreases
inversely with the square of the distance in the Far Field region. The maximum power density in
the Transition region will not exceed that calculated for the Near Field region. The power density
calculated in Section 1 is the highest power density the antenna can produce in any of the regions
away from the antenna. The power density at a distance R, can be determined from the following
equation:


Radiation Hazard Report                                 Page 3 of 6


  Transition Region Power Density   S = Sy Ra/R
                                      = 6.626 mW/icm*


Radiation Hazard Report                                                           Page 4 of 6


4.      Region between the Main Reflector and the Subreflector

Transmissions from the feed assembly are directed     toward the subreflector surface, and are
reflected back toward the main reflector. The most    common feed assemblies are waveguide
flanges, horms or subreflectors. The energy between   the subreflector and the reflector surfaces
can be calculated by determining the power density    at the subreflector surface. This can be
determined from the following equation:

     Power Density at the Subreflector                    S = 4000 P / Ag                       (6)
                                                            =771.161 mW/cm*

5.      Main Reflector Regio‘n

The power density in the main reflector is determined in the same manner as the power density at
the subreflector. The area is now the area of the main reflector aperture and can be determined
from the following equation:

     Power Density at the Main Reflector Surface      Ssurtace * 4 P / Asurface                 (7)
         .                                                    = 94.704 W/m*
                                                              = 9.470 mWicm"*

6.      Region between the Main Reflector and the Ground .

Assuming uniform illumination of the reflector surface, the power density between the antenna and
the ground can be determined from the following equation:

     Power Density between Reflector and Ground           Sy =P / Asurtace                      (8)
                .            '                                 = 23.676 W/im*
                                                               =2.368 mW/cm"


  Radiation Hazard Report                                                .            Page 5 of 6



  7.      Summary of Calculations

             Table 4. Summary of Expected Radiation levels for Uncontrolled Environment
                                                 Calculated Maximum
                                            Radiation Power Density Level
  Region                                                   ({mW/icm?*)              Hazard Assessment
  1. Far Field (Ry= 1496.0 m)                       Sy            2.038              . Potential   Hazard
  2. Near Field (Ry = 623.4 m)                      Sry           6.626                Potential   Hazard
  3. Transition Region (Ry< R< Ry)                  S,            6.626                Potential   Hazard
— 4.  Between     Main    Reflector and             Ssr         771161;                Potential   Hazard
      Subreflector
  5. Main Reflector                                 Sourface       9,470              Potential Hazard
  6. Between Main Reflector and Ground              Sq             2.368              Potential Hazard

              Table 5. Summary of Expected Radiation levels for Controlled Environment
                                                 Calculated Maximum
                                               Radiation Power Density
  Region                                            Level (mWicm*)                _ Hazard Assessment
  1. Far Field (R;= 1496.0 m)                       S¢        2.838          —_      Satisfies FCC MPE
  2. Near Field (Ry = 623.4 m)                       Sn       6.626                    Potential Hazard
  3. Transition Region (Ry< R,< Ry)                 S              6.626              Potential Hazard
  4. Between      Main    Reflector   and            Ssr        771161                Potential Hazard
       Subreflector
  5. Main Reflector                                  Ssurface      9.470              Potential Hazard
  6. Between Main Reflector and Ground               Sy            2.368             Satisfies FCC MPE

  It is the apphcant‘s responsibility to ensure that the public and operatlonal personnel are not /
  exposed to harmful levels of radiation.



  8.       Conclusions

  Based on this analysis it is concluded that the FCC RF Guidelines have been exceeded in the
  specific regions of Tables 4 and 5. The applicant proposes to comply with the Maximum
  Permissible Exposure (MPE) limits of 1 mW/cm2 for the Uncontrolled areas and the MPE limits of
  5 mW/cm2 for the Controlled areas by one or more of the following methods:

  Means 6f Compliance Uncontrolled Areas

  This antenna will be located in a fenced area, this area will be sufficient to prohibit access to the
  areas that exceed the MPE limited. The general public will not have access to areas within %
  diameter removed from the edge of the antenna.


Radiation Hazard Report                                      .                    Page 6 of 6
Since one ‘diameter removed from the main beam of the antenna or !4 diameter 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 will be in the areas that exceed the
MPE levels.


Means of Compliance Controlled Areas


The earth station‘s operational personnel will not have access to the areas that exceed the MPE
levels while the earth station is in operation.

The transmitters will be turned off during antenna maintenance.



Document Created: 2007-11-21 12:32:33
Document Modified: 2007-11-21 12:32:33

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