Attachment Exhibit C

This document pretains to SES-STA-20071120-01602 for Special Temporal Authority on a Satellite Earth Station filing.

IBFS_SESSTA2007112001602_606607

         EXHIBIT C

RADIATION HAZARD REPORT




  INTELSAT NORTH AMERICA LLC
   RASCom—1 LEOP STA REQUEST
     EARTH STATION E000296


  Radiation Hazard Report                                                                   Page 1 of 5

        Analysis of Non—lonizing Radiation for a 9.0—Meter Earth
                   ‘        Station System
  This report analyzes the non—ionizing radiation levels for a 9.0—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—field, 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/cm")
                            30—300                              0.2
                              300—1500                     Frequency (MHz)®(0.8/1200)
                            1500—100,000                                1.0

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

            Table 3. Formulas and Parameters Used for Determining PowerFlux Densities
       Parameter                     Symbol                Formula                 Value             Units
       Antenna Diameter                D                     Input                   9.0             m
       Antenna Surface Area       _ Asuface                 1D"/ 4                 63.62             m*
       Subreflector Diameter             Ds                  Input                  117.0            cm
       Area of Subreflector              Asr                x Ds "4               10751.32           cm*
       Frequency                         F                   Input            _     6182             MHz
       Wavelength                        A                  300 /F                0.048528           m
       Transmit Power                    P                    Input               2250.00            W
       Antenna Gain (dBi}            1 Ges_                   Input                 59.6     _       dBi
       Antenna Gain (factor)             G                   4 pces"0             229086.8           n/a
       Pi                                 T                 Constant              3.1415927          n/a
       Antenna Efficiency                n         _       _CGM(GD®)                0.67             n/a


Radiation Hazard Report                                                             Page 2 of 5


1.     .Far Field Distance Calculation

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

     Distance to theFar Field Region                        Ry =0.60 D/ x                          (1)
                                                               =1001.5 m
The maximum main beam power density in the far field can be determined from the following
equation:

     On—Axis Power Density in the Far Field                 S; =GP/(4r Ry")                        (2)
                                                               = 40.896 W/m*
                                                               = 4.090 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)
                                                                = 417.3 m
The maximum power density in the Near Field can be determined from the following equation:

     Near Field Power Density                          '    Sy =16.0 1 P / (x D)                   (4)
                                                                = 95.470 Wim*
                                                                =9.547 mWicm*

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:

     Transition Region Power Density                        S =Sy Ry/R                             (5)
                                        ,                       = 9.547 mW/icm*               Do


Radiation Hazard Report                                                       Page 3 of 5


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, horns 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                   Ssr = 4000 P / Agr                 (6)
                                                             = 837.107 mW/cm*

5.      Main Reflector Region

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 / Asurtace             (7)
                         '                                     =141.471 Wim"
                                                               = 14147 mWicm*


6.      Region between the Main Reflector and the Ground

Assuming uniform ilumination 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 / Agurface                   (8)
                                                            = 35.368 W/im*
                                                             =3.537 mW/cm*


Radiation Hazard Report                                                             Page 4 of 5


7.     Surhrnary of Calculations

          Table 4. Summary of Expected Radiation levels for Uncontrolled Environment
                                                Calculated Maximum
                                           Radiation Power Density Level
Region                                               (mW/iem*)                    Hazard Assessment
1. Far Field (R;= 1001.5 m)                        Sy           4.090               Potential Hazard
2. Near Field (Ry= 417.3 m)                        Sr           9.547               Potential Hazard
3. Transition Region (Ry < R< Ry)                  S,           9.547               Potential Hazard
4. Between      Main    Reflector    and           Ssr        837. 107              Potential Hazard
    Subreflector
5. Main Reflector                                   Scuface    ___14.147.           Potential Hazard
6. Between Main Reflector and Ground               S;           3.537               Potential Hazard

             Table 5. Summary of Expected Radiation levels for Controlled Environment
                                             Calculated Maximum
                                           Radiation Power Density
Region                                          Level (mW/icm*)             Hazard Assessment
1. Far Field (R;= 1001.5 m)                     S;          4.090            Satisfies FCC MPE
2. Near Field (Ry;= 417.3 m)                        Sy          9,547               Potential Hazard
3. Transition Region (Ry< R,< Rf)                   S,          9.547               Potential Hazard
4. Between       Main   Reflector and               Ssr       837.107               Potential Hazard
    Subreflector
5. Main Reflector                                   Scutace    ___14.147             Potential Hazard
6. Between Main Reflector and Ground                S;           3.537            . Satisfies FCC MPE

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



8.       Conclusions

This antenna will be located in a fenced area. The fenced are will be sufficient to prohibit the
general public from having access the areas that exceed the MPE limits

Since one diameter removed from the main beam of the antenna or 14 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 orother obstacles will be in the areas that exceed the
MPE levels.


  Radiation Hazard Report                                                     Page 5 of 5

  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 12:08:46
Document Modified: 2007-11-21 12:08:46

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