Attachment radhaz-wmp013.pdf

This document pretains to SES-LIC-20110412-00449 for License on a Satellite Earth Station filing.

IBFS_SESLIC2011041200449_860200

                                                             Radiation Hazard Analysis



                                                                      11.28 Meter WMP-013
                                                                      Bristow, Virginia 20136

                  Introduction
                  A radiation hazard anaylsis is presented for a 11.28 meter Ku band aperture antenna to be installed in BristowVirginia
                  at the SES WORLD SKIES Washington Mediaport. This Radiation Analysis calculates the non-ionizing radiation
                  levels expected to be emitted from the earth station on a worse cases basis and is performed in accordance with the
                  Federal Communications Commissions Office of Engineering and Technology (OET) Bulletin, No. 65.



                  Requirements
                  OET 65 outlines the maximum permissible exposure limits in two cases for operation in this frequency range.

                       1. The first case is the maximum level that a person may be exposed to in the general population. The exposure
                            limit is defined as a non-ionizing power level equal to 1 milliwatt per centimeter squared averaged over a thirty
                            minute period.
                       2. The second case is a controlled environment where the maximum permissible exposure limit must not exceed 5
                            milliwatts per centimeter squared averaged over any six minute period.

                  Summary
                  The results indicate that no significant hazard will be presented to the general population and will be fully mitigated in
                  the controlled area by the use of procedures that require the removal of transmit power before accessing the area
                  around the main reflector.


                  Analysis
                  This analysis was performed on seven zones with the results shown in Radiation Hazard Zones. The Table labeled
                  Input Values provides the - input data required to perform the analysis. The table labeled OET 65 Calculated Values
                  provides the intermediate calculation used to perform the assessment in accordance with OET 65. The Analysis is
                  performed for each a the each of seven radiation zones as shown in figure 1 – Analysis Zones. These zones are:


                       1. Point between the feed and the sub-reflector
                       2. The power at the surface of the antenna
                       3. The power level between the main reflector and ground
                       4. The near-field or Fresnel region in which the maxima can be reached before the field starts to diminish with
                          distance
                       5. The Transition region where power begins to decrease inversely with distance from the antenna
                       6. The Far Field or Fraunhofer region where power decreases inversely with the square of the distance. This is the
                          point at which the antenna beam is fully collimated
                       7. The off axis level in the near field. This is defined as the area outside of the main beam removed and at least one
                          antenna diameter removed from the main beam




Generated 12/17/2010                                                          1 of 2                                                   rad haz auto report-wmp013


                                                         Radiation Hazard Analysis

                                       Operator:              SES WORLD SKIES
                            Location Designation:             Washington Mediaport            FCC Callsign:
                                         County:              Prince William                       SES ID: WMP-013
                                           Town:              Bristow                                 STA:
                                       State/Zip:             Virginia       20136
                          Input Values                             Value         Unit                          Band          Frequency
                              D = Aperture Diameter                11.28           Meters                       L            1000-2000
                           d = Subreflector Diameter                 0.7           Meters                       S            2000-4000
                                  G = Antenna Gain                  62.8               dBi                      C            4000-8000
                                   FCC Designation                   Ku            Band                         X           8000-12500
                                      F = Frequency               14.250           GHz                          Ku          12500-18000
                        P = Transmitter Power Watts:               1859            Watts                        K           18000-25500
                  R ua = closest point to uncontrolled area          20           meters                        Ka          26500-40000
                  Elevation angle at closest point R ua              15           Degrees                       O           40000-50000
                                        Height (AGL)               5.18           meters                        V           50000-75000

                  OET 65 Calculated Values                      Formula            Value          Unit
                                                                    c
                                       λ= Wavelength                              0.0210     meters
                                                                    F
                                                                    (G/10)
                                   G = Antenna Gain              10            1905460.718 (W) linear
                                                                 Gλ2/4π
                          η = Apperture Efficiency                                     67%   percentage
                                                                  πD2/4
                               A = Area of reflector               πR2            99.933     meters 2
                            a = area of subreflector                πr2          3848.451    cm 2
                                                                    D2           1511.964    meters
                          R nf = Near-Field Region
                                                                    4λ             391       Meters AGL
                                                                   >Rnf          1511.964    >meters
                            R t = Transition Region
                                                                   <Rff          3628.714    <meters
                             R ff = Far Field Region              0.6D2          3628.714    meters
                                                                     λ             939       Meters AGL

                                                                                                                  Exposure Limits
              Radiation Analysis Zone                           Formula            Level         Value    General Public   Occupational
                                                                                                           <1mW/cm2     <5mW/cm2
                                                                    4P                                    >FCC MPE See >FCC MPE See
         1                       Power Subreflector                              1932.206       mW/cm2
                                                                     a                                       Note 1       Note 2
                                                                    4P                                    >FCC MPE See >FCC MPE See
         2                          Antenna Surface                                7.441        mW/cm2
                                                                     A                                       Note 1       Note 2
                                                                     P                                    >FCC MPE See
         3                  Main Reflector Ground                                  1.860        mW/cm2                  <FCC MPE
                                                                     A                                       Note 1
                                                                   4η P                                   >FCC MPE See
         4        S nf =Near-Field Power Density                                   4.997        mW/cm2                  <FCC MPE
                                                                     A                                       Note 1
                                                                                                          >FCC MPE See
         5    S t = Max Transition Power Density                   < Snf           4.997        mW/cm2                  <FCC MPE
                                                                                                             Note 1
                                                                    PG                                    >FCC MPE See
         6     S ff = Max Far field Power Density                                  2.141        mW/cm2                       <FCC MPE
                                                                  4πRff2                                     Note 3
         7       Off Access Level Near Field                    Snf - 20 dB       0.04997       mW/cm2      <FCC MPE         <FCC MPE

       Notes
         1. The antenna is installed in a controlled location access is restricted to authorized personnel only. The antenna is
            marked with RF Radiation Hazard signage.
         2. Inside the controlled area, MPE levels exceed the MPE exposure for occupational levels. The levels will be
            reduced to safe MPE by removing power to the transmitters when work is performed on or around the antenna.
            This area can only be accessed by qualified personnel.
          3. The field develops 5.18 meters above ground level at the minimum elevation angle which is not accessable to
             the general public.




Generated 12/17/2010                                                          2 of 2                                  rad haz auto report-wmp013



Document Created: 2010-12-17 13:13:05
Document Modified: 2010-12-17 13:13:05

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