Attachment Rad. Haz

This document pretains to SES-LIC-20170725-00795 for License on a Satellite Earth Station filing.

IBFS_SESLIC2017072500795_1232936

                                                     Radiation Hazard Analysis



                                                                     7.6 Meter
                                                                 Mt Airy, MD 21771

              Introduction
              A radiation hazard anaylsis is presented for a 7.6 meter Ku band aperture antenna to be installed in Mt AiryMD at
              the SESSES Woodbine. 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 5/31/2017                                                   1 of 2                                    rad haz auto report-tk-mod Woodbine


                                                          Radiation Hazard Analysis

                                        Operator:             SES
                             Location Designation:            SES Woodbine                       FCC Callsign:
                                          County:             Carroll                                 SES ID:
                                            Town:             Mt Airy                                    STA:
                                        State/Zip:            MD           21771
                          Input Values                            Value        Unit                                   Band          Frequency
                              D = Aperture Diameter               7.60              Meters                             L            1000-2000
                           d = Subreflector Diameter               0.8              Meters                              S           2000-4000
                                  G = Antenna Gain                59.3                  dBi                            C            4000-8000
                                   FCC Designation                 Ku               Band                               X           8000-12500
                                      F = Frequency              14.275              GHz                               Ku          12500-18000
                        P = Transmitter Power Watts:              390               Watts                              K           18000-25500
                  R ua = closest point to uncontrolled area        50              meters                              Ka          26500-40000
                  Elevation angle at closest point R ua            10              Degrees                             O           40000-50000
                                        Height (AGL)              2.00              meters                             V           50000-75000

                  OET 65 Calculated Values                      Formula             Value            Unit
                                                                      c
                                        λ= Wavelength                               0.0210     meters
                                                                      F
                                                                      (G/10)
                                   G = Antenna Gain              10              851138.0382   (W) linear
                                                                      2
                                                                 Gλ /4π
                           η = Apperture Efficiency                                     66%    percentage
                                                                 πD2/4
                                A = Area of reflector             πR2              45.365      meters 2
                                                                   πr
                                                                      2                           2
                             a = area of subreflector                             5026.548     cm
                                                                     2
                                                                   D              687.562      meters
                           R nf = Near-Field Region
                                                                   4λ               119        Meters AGL
                                                                  >Rnf            687.562      >meters
                             R t = Transition Region
                                                                  <Rff            1650.148     <meters
                                                                 0.6D2            1650.148     meters
                             R ff = Far Field Region
                                                                    λ               287        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                               310.352         mW/cm2
                                                                    a                                               Note 1           Note 2
                                                                   4P                                            >FCC MPE See
      2                              Antenna Surface                                3.439          mW/cm2                           <FCC MPE
                                                                    A                                               Note 1
                                                                   P
      3                     Main Reflector Ground                                   0.860          mW/cm2          <FCC MPE         <FCC MPE
                                                                    A
                                                                  4η P                                           >FCC MPE See
      4            S nf =Near-Field Power Density                                   2.265          mW/cm2                           <FCC MPE
                                                                    A                                               Note 1
                                                                                                                 >FCC MPE See
      5        S t = Max Transition Power Density                 < Snf             2.265          mW/cm2                           <FCC MPE
                                                                                                                    Note 1
                                                                   PG
      6         S ff = Max Far field Power Density                                  0.970          mW/cm2          <FCC MPE         <FCC MPE
                                                                 4πRff2
      7           Off Access Level Near Field                  Snf - 20 dB         0.02265         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 2 meters above ground level at the minimum elevation angle which is not accessable to the
            general public.




Generated 5/31/2017                                                            2 of 2                        rad haz auto report-tk-mod Woodbine



Document Created: 2017-05-31 15:58:42
Document Modified: 2017-05-31 15:58:42

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