Attachment RadHaz

This document pretains to SES-MOD-20150108-00003 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2015010800003_1072210

Radiation Hazard Report                                                             Page 1 of 5

      Analysis of Non—lonizing Radiation for a 2.4—Meter Earth
                          Station System
This report analyzes the non—lonizing radiation levels for a 2.4—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/cm*)
                              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/cm")
                              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                 2.4            m
     Antenna Surface Area          Asurtace          rD*/ 4                 4.52            m*
     Feed Flange Diameter              Di              Input                12.0            cm
     Area of Feed Flange               Ala           x Di, /4              113.10           cm*
     Frequency                          F              Input                6175            MHz
     Wavelength                         A            300 /F               0.048583          m
     Transmit Power                     P             Input                250.00           W
     Antenna Gain (dBi)                Ges             Input                41.5            dBi
     Antenna Gain (factor)              G             19%°"                14125.4          n/a
     Pi                                 I           Constant             3.1415927          n/a
     Antenna Efficiency                 n           GMIQD®)                 0.59            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                         Ru =0.60 0° /A                      (1)
                                                                =71.1 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 Rr")                   (2)
                                                                = 55.533 W/im*
                                                                = 5.553 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)
                                                                =29.6 m
The maximum power density in the Near Field can be determined from the following equation:

    Near Field Power Density                                Sa = 16.0 71 P / (1 D°)             (4)
                                                                = 129.638 W/m*
                                                                = 12.964 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 = Sar Ra/ Ri                      (5)
                                                                = 12.964 mW/cm*


Radiation Hazard Report                                                          Page 3 of 5
Region between the Feed Assembly and the Antenna Reflector

Transmissions from the feed assembly are directed toward the antenna reflector surface, and are
confined within a conical shape defined by the type of feed assembly. The most common feed
assemblies are waveguide flanges, horns or subreflectors. The energy between the feed assembly
and reflector surface can be calculated by determining the power density at the feed assembly
surface. This can be determined from the following equation:

   Power Density at the Feed Flange                       Si, = 4000 P / Aj4                   (6)
                                                              = 8841.941 mW/cm*
4. Main Reflector Region

The power density in the main reflector is determined in the same manner as the power density at
the feed assembly. The area is now the area of the reflector aperture and can be determined from
the following equation:

   Power Density at the Reflector Surface             Ssurtace =4 P / Asurtace                 (7)
                                                              = 221.049 W/m*
                                                              = 22.105 mW/cm*


5. Region between the 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)
                                                              = 55.262 W/m*
                                                              = 5.526 mW/cm*


Radiation Hazard Report                                                        Page 4 of 5
6. 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 (Ry=71.1 m)_                          Sn            5.553         Potential Hazard
2. Near Field (R.; = 29.6 m)                       Sn           12.964         Potential Hazard
3. Transition Region (Ry < R, < Ry)                S            12.964         Potential Hazard
4. Between     Feed    Assembly       and          Sia        8841.941         Potential Hazard
   Antenna Reflector
5. Main Reflector                                  Scurtace     22105          Potential Hazard
6. Between Reflector and Ground                    S             5.526         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 (Ry=71.1 m)                       Sn          5.553             Potential Hazard
2. Near Field (R,, = 29.6 m)                   Sat        12.964             Potential Hazard
3. Transition Region (Ry < R,< Ri)                 S            12.964         Potential Hazard
4. Between     Feed    Assembly       and          Sia        8841.941         Potential Hazard
   Antenna Reflector
5. Main Reflector                                  Scurtace     __22.105       Potential Hazard
6. Between Reflector and Ground                    Sq             5.526        Potential Hazard

It is the applicant‘s responsibility to ensure that the public and operational personnel are not
exposed to harmful levels of radiation.




7. Conclusions
Based on this analysis it is concluded that the FCC RF Guidelines have been exceeded in the
specific regions of Tables 4 and 5. The applicant proposes to comply with the Maximum
Permissible Exposure (MPE) limits of 1 mW/cm2 for the uncontrolled areas and the MPE limits of
5 mW/cm2 for the Controlled areas by one or more of the following methods:


Means of Compliance Uncontrolled Areas

The antenna will be located on top of a truck. The bottom lip of the dish will be 3.50 meters above
ground level. The general public will not have access to areas within % diameter from the edge of
the antenna.


Radiation Hazard Report                                                           Page 5 of 5
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.

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


Means of Compliance Controlied Areas

The earth station‘s operational personnel 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.


Prepared by


Timothy O Crutcher
Comserch
01/05/2015


Radiation Hazard Report                                                             Page 1 of 5

      Analysis of Non—lonizing Radiation for a 2.4—Meter Earth
                          Station System
This report analyzes the non—fonizing radiation levels for a 2.4—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) limits for persons in a General Population/Uncontroiled 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/cm*)
                              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/cm*)
                             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                 2.4             m
     Antenna Surface Area          Asurtace          rD*/ 4                 4.52            m*
     Feed Flange Diameter              Dis            Input                 12.0            cm
     Area of Feed Flange               Ara           x Di 4                113.10           cm"
     Frequency                          F             Input                14250            MHz
     Wavelength                         A            300 /F               0.021053          m
     Transmit Power                     P             Input                150.00           W
     Antenna Gain (dBi)                Gieg           Input                 49.0            dBi
     Antenna Gain (factor)              G            10C®="°              79432.8           n/a
     Pi                                 x           Constant             3.1415927          na
     Antenna Efficiency                 n           GRIGCD®)                0.62            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                         Ra =0.60 D*/A                        (1)
                                                               =164.2 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 rRy")                      (2)
                                                                  = 85.184 W/m*
                                                                  =3.518 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                                 Ru = D*/ (4 ¥)                       (3)
                                                                  = 68.4 m

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

   Near Field Power Density                                 Sa =16.0 71 P/(rD")                  (4)
                                                                  = 82.135 W/im*
                                                                  = 8.214 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, =Su Ru/R                          (5)
                                                                  = 8.214 mW/cm*


Radiation Hazard Report                                                          Page 3 of 5
Region between the Feed Assembly and the Antenna Reflector

Transmissions from the feed assembly are directed toward the antenna reflector surface, and are
confined within a conical shape defined by the type of feed assembly. The most common feed
assemblies are waveguide flanges, horns or subreflectors. The energy between the feed assembly
and reflector surface can be calculated by determining the power density at the feed assembly
surface. This can be determined from the following equation:

   Power Density at the Feed Flange                       Sia = 4000 P / Aia                   (6)
                                                              = 5305.165 mW/cm*

4. Main Reflector Region

The power density in the main reflector is determined in the same manner as the power density at
the feed assembly. The area is now the area of the reflector aperture and can be determined from
the following equation:

   Power Density at the Reflector Surface             Ssurtace =4 P / Asurtace                 (7)
                                                              = 132.629 W/m*
                                                              = 13.263 mW/cm*


5. Region between the 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)
                                                              = 33.157 W/m*
                                                              = 3.316 mW/cm*


Radiation Hazard Report                                                        Page 4 of 5
6. 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 (Ry = 164.2 m)                          Sn          3.518         Potential Hazard
2. Near Field (R;; = 68.4 m)                         Sat         8.214         Potential Hazard
3. Transition Region (Ry; < R; < Rn)                S,            8.214        Potential Hazard
4.  Between Feed Assembly              and          Sia        5305.165        Potential Hazard
    Antenna Reflector
5. Main Reflector                                   Ssurtace     13.263        Potential Hazard
6. Between Reflector and Ground                     Sq            3.316        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 (Ry = 164.2 m)                         Sn        3.518           Satisfies FCC MPE
2. Near Field (R.; = 68.4 m)                        Sat           8.214        Potential Hazard
3. Transition Region (Ry < R;< Ry)                  S,            8.214        Potential Hazard
4.   Between Feed Assembly             and          Sia        5305.165        Potential Hazard
     Antenna Reflector
5. Main Reflector                                   Scuriace     13263         Potential Hazard
6. Between Reflector and Ground                     Sq            3.316      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.


7. Conclusions

Based on this analysis it is concluded that the FCC RF Guidelines have been exceeded in the
specific regions of Tables 4 and 5. The applicant proposes to comply with the Maximum
Permissible Exposure (MPE) limits of 1 mW/cm2 for the uncontrolled areas and the MPE limits of
5 mW/cm2 for the Controlled areas by one or more of the following methods:


Means of Compliance Uncontrolled Areas

The antenna will be located on top of a truck. The bottom lip of the dish will be 3.50 meters above
ground level. The general public will not have access to areas within 4 diameter from the edge of
the antenna.


Radiation Hazard Report                                                           Page 5 of 5
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.

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 personnel 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.

Prepared by


Timothy O Crutcher
Comsearch
01/05/2015



Document Created: 2015-01-05 11:18:11
Document Modified: 2015-01-05 11:18:11

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