Attachment NWM-15 11m Ku rad ha

This document pretains to SES-LIC-20130116-00054 for License on a Satellite Earth Station filing.

IBFS_SESLIC2013011600054_978162

                                                   Radiation Hazard Analysis



                                                             11.1 Meter NWM-15
                                                            Bristow, Virginia 20136

            Introduction
            A radiation hazard anaylsis is presented for a 11.1 meter C band aperture antenna to be installed in
            BristowVirginia at the SES 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 12/13/2012                                                1 of 2                                 NWM-15 11m Ku rad haz auto report


                                                       Radiation Hazard Analysis



                                     Operator:             SES
                          Location Designation:            Washington Mediaport              FCC Callsign:
                                       County:             Prince William                         SES ID: NWM-15
                                         Town:             Bristow                                   STA:
                                     State/Zip:            Virginia       20136
                       Input Values                             Value         Unit                              Band          Frequency
                           D = Aperture Diameter               11.10            Meters                           L             1000-2000
                        d = Subreflector Diameter               1.37            Meters                           S             2000-4000
                               G = Antenna Gain                  62                 dBi                          C             4000-8000
                                FCC Designation                  C              Band                             X            8000-12500
                                   F = Frequency               14.125           GHz                              Ku          12500-18000
                     P = Transmitter Power Watts:               1200            Watts                            K           18000-25500
               R ua = closest point to uncontrolled area         20            meters                            Ka          26500-40000
               Elevation angle at closest point R ua             10            Degrees                           O           40000-50000
                                     Height (AGL)               3.47           meters                            V           50000-75000

               OET 65 Calculated Values                      Formula            Value            Unit
                                                                 c
                                     λ= Wavelength                              0.0212     meters
                                                                 F
                                                                 (G/10)
                                G = Antenna Gain              10             1584893.192   (W) linear
                                                              Gλ2/4π
                        η = Apperture Efficiency                                    59%    percentage
                                                               πD2/4
                             A = Area of reflector              πR2             96.769     meters 2
                          a = area of subreflector               πr2          14741.138    cm 2
                                                                 D2            1451.252    meters
                        R nf = Near-Field Region
                                                                 4λ              252       Meters AGL
                                                                >Rnf           1451.252    >meters
                          R t = Transition Region
                                                                <Rff           3483.005    <meters
                          R ff = Far Field Region              0.6D2           3483.005    meters
                                                                  λ              605       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                              325.619         mW/cm2
                                                                  a                                           Note 1       Note 2
                                                                 4P                                        >FCC MPE See
    2                             Antenna Surface                               4.960          mW/cm2                    <FCC MPE
                                                                  A                                           Note 1
                                                                 P                                         >FCC MPE See
    3                    Main Reflector Ground                                  1.240          mW/cm2                    <FCC MPE
                                                                  A                                           Note 1
                                                                4η P                                       >FCC MPE See
    4           S nf =Near-Field Power Density                                  2.912          mW/cm2                    <FCC MPE
                                                                  A                                           Note 1
                                                                                                           >FCC MPE See
    5       S t = Max Transition Power Density                  < Snf           2.912          mW/cm2                    <FCC MPE
                                                                                                              Note 1
                                                                 PG                                        >FCC MPE See
    6        S ff = Max Far field Power Density                                 1.248          mW/cm2                         <FCC MPE
                                                               4πRff2                                         Note 3
    7          Off Access Level Near Field                   Snf - 20 dB       0.02912         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 3.47 meters above ground level at the minimum elevation angle which is not accessable to the
          general public.




Generated 12/13/2012                                                       2 of 2                       NWM-15 11m Ku rad haz auto report



Document Created: 2012-12-13 11:05:08
Document Modified: 2012-12-13 11:05:08

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