Attachment Attachment RH

This document pretains to SES-LIC-20160229-00181 for License on a Satellite Earth Station filing.

IBFS_SESLIC2016022900181_1128379

Radiation Hazard Report_                                                            _Page 1 of 5

      Analysis of Non—lonizing Radiation for a 3.0—Meter Earth
                          Station System
This report analyzes the non—lonizing radiation levels for a 3.0—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/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                  3.0             m
     Antenna Surface Area          Asurtace          r D/ 4                 7.07             m*
     Subreflector Diameter           Dsr              Input                 36.0             cm
     Area of Subreflector              Asr           1 Ds, 4               1017.88           cm*
     Frequency                          F             Input                14250             MHz
     Wavelength                         A            300 /F               0.021053           m
     Transmit Power                     P             Input                350.00            W
     Antenna Gain (dBi)                Ges            Input                  50.9            dBi
     Antenna Gain (factor)              G            194es"*              123026.9           nwa
     Pi                                 r           Constant             3.1415927           n/a
     Antenna Efficiency                 1           G62M(AD)                 0.61            wa


Radiation Hazard Report                                    —          _        ___ Page2of5_



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)
                                                                  = 256.5 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/(4 x Ry*)                 (2)
                                                                  = 52.081 W/im*
                                                                  = 5.208 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/ (4 A)                    (3)
                                                                  = 106.9 m
The maximum power density in the Near Field can be determined from the following equation:

    Near Field Power Density                                   Si = 16.0 n P / (x D)            (4)
                                                                  = 121.581 W/im*
                                                                  = 12.158 mW/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 Rar/ R:                   (5)
                                                                 =12.158 mW/icm*


Radiation Hazard Report                                     o                    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 / A;,                 (6)
                                                               = 1375.413 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        Scutace 74 P / Asurtace                  (7)
                                                               = 198.059 W/im*
                                                               = 19.806 mW/icm*


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              Sq =P / Asurtace                   (8)
                                                               =49.515 W/m*
                                                               =4.951 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                                              (mWicm?)                Hazard Assessment
1. Far Field (R; = 256.5 m)                     S«          5.208             Potential Hazard
2. Near Field (R,; = 106.9 m)                   Sar        12.158             Potential Hazard
3. Transition Region (Ry < R, < Ry)             S,         12.158             Potential Hazard
4. Between        Main   Reflector  and         Ssr      1375.413             Potential Hazard
    Subreflector
5. Main Reflector                               Ssurtace   __19.806           Potential Hazard
6. Between Main Reflector and Ground                 Sq          4.951              Potential Hazard

            Table 5. Summary of Expected Radiation levels for Controlled Environment
                                                   Calculated Maximum
                                                 Radiation Power Density
Region                                               Level (mW/cm")               Hazard Assessment
1. Far Field (R;= 256.5 m)                           S¢        5.208                Potential Hazard
2. Near Field (R.: = 106.9 m)                        Sn       12.158                Potential Hazard
3. Transition Region (Ry < R, < Ry)                  S        12.158                Potential Hazard
4. Between       Main    Reflector  and              Ssr    1375.413                Potential Hazard
    Subreflector
5. Main Reflector                                    Scurtace   __19.806           Potential Hazard
6. Between Main Reflector and Ground                 S;          4.951            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 Uncontrolied Areas

This antenna will be located in a fenced area. The fenced area will not be accessible to the
general public.

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


RadiationHazard Report                                                          Page 5 of 5
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 station‘s operational staff 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

The applicant agrees to abide by the conditions specified in Condition 5208 provided below:

Condition 5208 — The licensee shall take all necessary measures to ensure that the antenna does
not create potential exposure of humans to radiofrequency radiation in excess of the FCC
exposure limits defined in 47 CFR 1.1307(b) and 1.1310 wherever such exposures might occur.
Measures must be taken to ensure compliance with limits for both occupational/controlled
exposure and for general population/uncontrolled exposure, as defined in these rule sections.
Compliance can be accomplished in most cases by appropriate restrictions such as fencing.
Requirements for restrictions can be determined by predictions based on calculations, modeling or
by field measurements. The FCC‘s OET Bulletin 65(available on—line at www.fco.gov/oet/rfsafety)
provides information on predicting exposure levels and on methods for ensuring compliance,
including the use of warning and alerting signs and protective equipment for worker.


1 HEREBY CERTIFY THAT | AM THE TECHNICALLY QUALIFIED PERSON RESPONSIBLE
FOR THE PREPARATION OF THE RADIATION HAZARD REPORT, AND THAT IT is
COMPLETE AND CORRECT TO THE BEST OF MY KNOWLEDGE AND BELIEF.



Timothy O. Crutcher
COMSEARCH
19700 Janelia Farm Boulevard
Ashburn, VA 20147


Radiation HazardReport                                                          __Page 1 of5
      Analysis of Non—lonizing Radiation for a 4.5—Meter Earth
                          Station System
This report analyzes the non—ionizing radiation levels for a 4.5—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 Builletin, 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) timits 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                 4.5            m
     Antenna Surface Area          Asurtace          x D/ 4                 15.90          m*
     Subreflector Diameter             Dsr             Input                51.0           cm
     Area of Subreflector              Agr           x Ds, "/4            2042.82          cm*
     Frequency                          F              Input                6175           MHz
     Wavelength                         A            300 /F               0.048583         m
     Transmit Power                     P              Input               226.00          W
     Antenna Gain (dBi)                Ges             Input                47.3           dBi
     Antenna Gain (factor)              G             o                    53703.2         n/a
     Pi                                 x           Constant             3.1415927         n/a
     Antenna Efficiency                 n           Gr2(GD®)                0.63           n/a


Radiation Hazard Report                                                         Page 2 of 5



1. Far Field Distance Calculation

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

   Distance to the Far Field Region                        Ry; =0.60 D@ /A                     (1)
                                                               = 250.1 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                  S4, =GP/(4 1 R,*)                   (2)
                                                               =15.442 W/im
                                                               = 1.544 mWicm*

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                                Ra = D* / (4 )                     (3)
                                                               = 104.2 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)
                                                               = 36.049 W/im
                                                               = 3.605 mW/cm*

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 Rar/ R                      (5)
                                                               = 3.605 mW/cm*


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 / Ay,                   (6)
                                                                 = 442.525 mWi/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 74 P / Asurtace                   (7)
                                                                 = 56.840 W/im*
                                                                 = 5.684 mW/icm*


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               Sg     =P / Asurtace                 (8)
                                                                   14.210 W/im"
                                                                   1.421 mWicm*


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                                                    {mW/icm?)               Hazard Assessment
1. Far Field (R; = 250.1 m)                         S¢           1.544              Potential Hazard
2. Near Field (R,; = 104.2 m)                       Sat          3.605              Potential Hazard
3. Transition Region (Ry < R;< Ry)                  S,           3.605              Potential Hazard
4. Between      Main     Reflector and              Ssr        442.525              Potential Hazard
    Subreflector
5. Main Reflector                                   Ssurtace     5.684              Potential Hazard
6. Between Main Reflector and Ground                So           1.421              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 (R4 = 250.1 m)                        Sr         1.544                Satisfies FCC MPE
2. Near Field (Ry = 104.2 m)                       Sar        3.605                Satisfies FCC MPE
3. Transition Region (Ry < R, < Ry4)                S            3.605            Satisfies FCC MPE
4. Between      Main   Reflector     and            Ssr        442.525             Potential Hazard
    Subreflector
5. Main Reflector                                   Ssurtace     5.684             Potential Hazard
6. Between Main Reflector and Ground                Sq           1.421            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 fenced area will not be accessible to the
general public.

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


Radiation Hazard Report                                                ______   PageSofs
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 station‘s operational staff 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

The applicant agrees to abide by the conditions specified in Condition 5208 provided below:

Condition 5208 — The licensee shall take all necessary measures to ensure that the antenna does
not create potential exposure of humans to radiofrequency radiation in excess of the FCC
exposure limits defined in 47 CFR 1.1307(b) and 1.1310 wherever such exposures might occur.
Measures must be taken to ensure compliance with limits for both occupational/controlled
exposure and for general population/uncontrolled exposure, as defined in these rule sections.
Compliance can be accomplished in most cases by appropriate restrictions such as fencing.
Requirements for restrictions can be determined by predictions based on calculations, modeling or
by field measurements. The FCC‘s OET Bulletin 65(available on—line at www.fec.gov/oet/rfsafety)
provides information on predicting exposure levels and on methods for ensuring compliance,
including the use of warning and alerting signs and protective equipment for worker.


1 HEREBY CERTIFY THAT | AM THE TECHNICALLY QUALIFIED PERSON RESPONSIBLE
FOR THE PREPARATION OF THE RADIATION HAZARD REPORT, AND THAT IT IS
COMPLETE AND CORRECT TO THE BEST OF MY KNOWLEDGE AND BELIEF.



Timothy 0. Crutcher
COMSEARCH
19700 Janelia Farm Boulevard
Ashburn, VA 20147



Document Created: 2019-04-25 16:42:33
Document Modified: 2019-04-25 16:42:33

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