Attachment RadHaz

This document pretains to SES-LIC-20100811-01024 for License on a Satellite Earth Station filing.

IBFS_SESLIC2010081101024_834445

 Radiation Hazard Report                                                                   Page 1 of 5

     Analysis of Non—lonizing Radiation for a 7.3—Meter C—Band
                       Earth Station System
This report analyzes the non—ionizing radiation levels for a 7.3—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/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/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 Power Flux Densities
     Parameter                       Symbol              Formula                Value             Units
     Antenna Diameter                   D                  Input                 7.3              m
     Antenna Surface Area             Asurface            1 D/ 4                41.85             m*
     Subreflector Diameter              M                     Input              104.2            cm
     Area of Subreflector               Asr              1 Ds /4               8527.57            cm*
     Frequency                           F                 Input                6175              MHz
     Wavelength                          A                300 /F              0.048583            m
     Transmit Power                      P                 Input               358.00             W
     Antenna Gain (dBi)                 Ges                Input                51.7              dBi
     Antenna Gain (factor)              G                 1909                147910.8            n/a
     Pi                                  I               Constant            3.1415927            na
     Antenna Efficiency                  n              GA/(RD")                 0.66             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 the Far Field Region                       R; =0.60 D°/a                       (1)
                                                                =658.1 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/(4 1 R;")                    (2)
                                                                = 9.729 Wim*
                                                                = 0.973 mW/icm*

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/ (4 )                        (3)
                                                               =274.2 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 / (1 D°)              (4)
                                                                =22.711 Wim*
                                                                = 2271 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                        Se = Sy Ra/R                        (5)
                                                                =2.271 mWicm*


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                    Ss = 4000 P / Agr                    (6)
                                                              = 167.926 mW/icm*

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)
                                                              = 34.214 Wim"
                                                              = 3.421 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)
                                                              = 8.554 W/im"
                                                              = 0.855 mW/icm"


Radiation Hazard Report                                                         Page 4 of 5


7.      Summary of Calculations
           Table 4. Summary of Expected Radiation levels for Uncontrolled Environment
                                             Calculated Maximum
                                        Radiation Power Density Level
Region                                                  ({mWi/cm*)            Hazard Assessment
1. Far Field (R; = 658.1 m)                       S¢           0.973           Satisfies FCC MPE
2. Near Field (Ry: = 274.2 m)                     Sn           2.271            Potential Hazard
3. Transition Region (Ry< R,< R&)                 S;           2.271            Potential Hazard
4. Between      Main     Reflector   and          Ss         167.926            Potential Hazard
   Subreflector
5. Main Reflector                                 Scurface     3.421            Potential Hazard
6. Between Main Reflector and Ground              S;           0.855           Satisfies FCC MPE

            Table 5. Summary of Expected Radiation levels for Controlled Environment
                                            Calculated Maximum
                                          Radiation Power Density
Region                                            Level (mWicm*)             Hazard Assessment
1. Far Field (R; = 658.1 m)                        S¢       0.973             Satisfies FCC MPE
2. Near Field (R»; = 274.2 m)                      Sr       2.271             Satisfies FCC MPE
3. Transition Region (Ry <R,< R;)                 S;           2.271          Satisfies FCC MPE
4. Between      Main   Reflector  and             Ssr        167.926           Potential Hazard
     Subreflector
5. Main Reflector               j                 Surface      3.421          Satisfies FCC MPE
6. Between Main Reflector and Ground              S;           0.855          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

Based on the above analysis it is concluded that the FCC MPE guidelines have been exceeded (or
met) in the regions of Table 4 and 5. The applicant proposes to comply with the MPE limits by one
or more of the following methods.

Means of Compliance Uncontrolled Areas

This antenna will be located in a fenced area. The 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.

Since one diameter removed from the main beam of the antenna or %% 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 Report                                                           Page 5 of 5

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 stations operational 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.


Radiation Hazard Report                                                             Page 1 of 5

   Analysis of Non—lonizing Radiation for a 7.3— Meter Ku—Band
                      Earth Station System
This report analyzes the non—lonizing radiation levels for a 7.3—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 (mWicm*)
                            30—300                            0.2
                           300—1500                Erequency (MHz)®(0.8/1200)
                         1500—100,000                         1.0
                    Table 2. Limits for Occupational/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 Power Flux Densities
    Parameter                     Symbol            Formula                Value           Units
    Antenna Diameter                  D               Input                 7.3            m
    Antenna Surface Area           Asurface          1 D/ 4                41.85           m*
    Subreflector Diameter            Dr               Input                104.2           cm
    Area of Subreflector              Asr            x Ds "/4             8527.57          cm*
    Frequency                          F              Input               14250            MHz
    Wavelength                         A.            300 /F              0.021053          m
    Transmit Power                     P              Input               358.00           W
    Antenna Gain (dBi)                Geg             Input                 58.1           dBi
    Antenna Gain (factor)              G             19%°"               645654.2          nia
     Pi                                T            Constant             3.1415927         n/a
    Antenna Efficiency                 n           GM(RD)                   0.54           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 the Far Field Region                       Ry =0.60 D@ /A                      (1)
                                                                =1518.8 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/(4 1 Ry")                    (2)
                                                               = 7.974 Wim?
                                                               = 0.797 mW/icm*

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)
                                                               = 632.8 m

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

     Near Field Power Density                               Sir = 16.0 1 P / (1 D)              (4)
                                                               =18.616 W/im*
                                                               = 1.862 mWi/icm"

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 = Sn Rau/R                         (5)
                                                             = 1.862 mWicm*


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 / Ag;                    (6)
                                                              = 167.926 mWicm"

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)
                                                              = 34.214 Wim*
                                                              = 3.421 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)
                                                              = 8.554 W/im"
                                                              = 0.855 mW/cm*


Radiation Hazard Report                     —                                   Page 4 of 5



7.      Summary of Calculations

           Table 4. Summary of Expected Radiation levels for Uncontrolled Environment
                                                  Calculated Maximum
                                           Radiation Power Density Level
Region                                               (mWicm?)                 Hazard Assessment
1. Far Field (R;= 1518.8 m)                         S¢           0.797         Satisfies FCC MPE
2. Near Field (R,; = 632.8 m)                       Sn           1.862          Potential Hazard
3. Transition Region (Ry < R,< Ry)                  S;           1.862          Potential Hazard
4. Between       Main    Reflector   and            Ssr        167.926          Potential Hazard
     Subreflector
5. Main Reflector                                   Ssurface     3.421          Potential Hazard
6. Between Main Reflector and Ground                S;           0.855         Satisfies FCC MPE

            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;= 1518.8 m)                         S¢           0.797        Satisfies FCC MPE
2. Near Field (Ry; = 632.8 m)                       Sn           1.862        Satisfies FCC MPE
3. Transition Region (Ry < R;< Ry)                  S            1.862        Satisfies FCC MPE
4. Between      Main   Reflector   and              Ssr        167.926         Potential Hazard
    Subreflector
5. Main Reflector                                   Ssurface     3.421        Satisfies FCC MPE
6. Between Main Reflector and Ground                S;           0.855        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
Based on the above analysis it is concluded that the FCC MPE guidelines have been exceeded (or
met) in the regions of Table 4 and 5. The applicant proposes to comply with the MPE limits by one
or more of the following methods.

Means of Compliance Uncontrolled Areas

This antenna will be located in a fenced area. The 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.

Since one diameter removed from the main beam of the antenna or %% 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 Report                                                           Page 5 of 5

Radiation hazard signs will be posted while this earth station is in operation.

The applicant will ensure that no buildings or other obstacies will be in the areas that exceed the
MPE levels.



Means of Compliance Controlled Areas


The earth stations operational 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: 2019-04-28 05:38:42
Document Modified: 2019-04-28 05:38:42

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