Attachment Exhibit A

This document pretains to SES-LIC-20190419-00546 for License on a Satellite Earth Station filing.

IBFS_SESLIC2019041900546_1659156

                                                                                                     Exhibit A


Radiation Hazard Report
Analysis of Non-Ionizing Radiation for a 1 m Earth Station
This analysis provides the calculated non-ionizing radiation levels for a 1-meter earth station system.


The methods and calculations performed in this analysis are based on the FCC Office of Engineering and
Technology Bulletin, No.65, October 1985 as 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 (Summarized in Annex 1). There are separate
exposure limits applicable to the General Population/Uncontrolled Environment and the Occupational/Controlled
Environment. The Maximum Permissible Exposure (MPE) limits for persons in a General Population/Uncontrolled
environment for the frequency band of this antenna, is 1 mW/cm2 for a 30 minute or lower time period as shown in
Annex 1 (a). The MPE limit for persons in an Occupational/Controlled environment for the frequency band of this
antenna is 5 mW/cm2 for a 6 minute time or lower period as shown in Annex 1 (b). The purpose of this analysis
described is to determine the power flux density levels of the earth station at the main reflector surface, the near-
field, transition region, far-field, between the sub-reflector or feed and, at the main reflector surface, and between
the antenna edge and the ground and to compare these levels to the specified MPEs.



The parameters of the antenna that is the subject of this analysis are shown in Table 1.
Intermediate calculated values and constants are provided in Table 2.

 Table 1. Input Parameters Used for Determining Power Flux Densities
                 Parameter                    Symbol      Formula              Value                 Units
Antenna Diameter                                 D          Input                 1                    m
Frequency                                        F          Input              14000                 MHz
Transmit Power                                   P          Input                25                   W
Antenna Gain (dBi)                              G es        Input               41.7                  dBi

 Table 2. Calculated Values and Constants
                 Parameter                        Symbol       Formula         Value                 Units
Antenna Surface Area                               Asurface      πD2/4          0.79                 m^2
Wavelength                                           λ           300/F       0.021429                 m
Antenna Gain (factor)                                G          10Ges/10     14791.08                 n/a
Pi                                                   π         Constant      3.1415927                n/a
Antenna Efficiency                                   η        Gλ2 /( π2D2)      0.69                  n/a




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1. Antenna Main Reflector Surface
The power density in the main reflector is determined from the Power level and the area of the main reflector
aperture. This is determined from the following equation:

              Power Density at the Main Reflector Surface:

                                         Ssurface = 4P/Asurface                          (1)
                                                                                2
                                                             =    127.324   W/m
                                                             =     12.732   mW/cm2

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 is determined from the following equation:


                                   Extent of the Near Field:

                                               Rnf = D2 / (4λ)                           (2)
                                                             =     11.67    m

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

                                        Near Field Density:

                                      Snf = 16.0 η P / (π D2)                            (3)
                                                                                    2
                                                           =       8.762    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 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 Rt is determined from the following
equation:

                          Transition Region Power Density:

                                              St = Snf Rnf / Rt                          (4)
                                                                                    2
                                                             =     8.762    mW/cm




                                                            2


4. Far Field Distance Calculation
The distance to the Far Field Region is calculated using the following equation:

                              Distance to Far Field Region:

                                              Rff = 0.6 D2 / λ                         (5)
                                                             =   28.000   m

The maximum main beam power density in the far field is determined from the following equation:

                    On-axis Power Density in the Far Field:

                                        Sff = G P / (4 π Rff2)                         (6)
                                                                                   2
                                                            =    3.753    mW/cm

5. Region between the Main Reflector and the Ground
Assuming uniform illumination of the reflector surface, the power density between the antenna and the ground is
determined from the following equation:

             Power Density between Reflector and Ground:

                                             Sg = P / Asurface                         (7)
                                                            =    3.183        mW/cm2




                                                           3


7. Summary of Calculations

 Table 3. Summary of Expected Radiation levels for Uncontrolled Environment
                                                                       Calculated
                                                                        Maximum
                                                                        Radiation
                       Region                               Symbol        Power              Hazard Assessment
                                                                         Density
                                                                          Level
                                                                        (mW/cm2)
1. Main Reflector                                                Ssurface      12.732           Potential Hazard

2. Near Field                         (Rnf =    11.67 m)           Snf          8.762           Potential Hazard

3. Transition Region (Rnf <Rt< Rff)                                St           8.762           Potential Hazard

4. Far Field                          (Rff =    28 m)              Sff          3.753           Potential Hazard

5. Between Main Reflector and Ground                               Sg           3.183           Potential Hazard


Table 4. Summary of Expected Radiation levels for Controlled Environment
                                                                       Calculated
                                                                       Maximum
                                                                       Radiation
                       Region                               Symbol       Power               Hazard Assessment
                                                                         Density
                                                                          Level
                                                                       (mW/cm2)
1. Main Reflector                                                Ssurface      12.732           Potential Hazard

2. Near Field                         (Rnf =    11.67 m)           Snf          8.762           Potential Hazard

3. Transition Region (Rnf <Rt< Rff)                                St           8.762           Potential Hazard

4. Far Field                          (Rff =    28 m)              Sff          3.753         Satisfies FCC MPE

5. Between Main Reflector and Ground                               Sg           3.183         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.




                                                           4


8. Conclusion
Based upon the above analysis, it is concluded that harmful levels of radiation may exist in those regions noted for
the Uncontrolled (Table 3) Environment and the Controlled Environment (Table 4).

The antenna will be located in Nationwide (transportable).
The antenna is in a facility with secured access in and around the proposed antenna. The earth station will be
marked with the standard radiation hazard warnings, as well as the area in the vicinity of the earth station to inform
those in the general population, who might be working or otherwise present in or near the direct path of the main
beam.


The applicant will ensure that the main beam of the antenna will be pointed at least one diameter away from any
building, or other obstacles in those area that exceed the MPE levels. Since one diameter removed from the
center of the main beam the levels are down by at least 20 dB, or by a factor of 100, these potential hazards do not
exist for either the public, or for earth station personnel.


Finally, the earth station’s operating personnel will not have access to areas that exceed the MPE levels, while the
earth station is in operation. The transmitter will be turned off during those periods of maintenance, so that the
MPE standard of 5.0 mW/cm 2 will be complied with for those regions in close proximity to the main reflector, which
could be occupied by operating personnel.


 “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.fcc.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 workers.”




                                                          5


                                   ANNEX 1
                                  (MPE Levels)

a) Limits for General Population/Uncontrolled Exposure (MPE)
        Frequency Range (MHz)                      Power Density (mW/cm2)
                30-300                                       0.2
               300-1500                           Frequency(MHz)*(4.0/1200)
             1500-100,000                                     1

b) Limits for Occupational/Controlled Exposure (MPE)
         Frequency Range (MHz)                     Power Density (mW/cm2)
                  30-300                                     1
                 300-1500                         Frequency(MHz)*(4.0/1200)
               1500-100,000                                  5




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Document Created: 2019-04-01 09:41:35
Document Modified: 2019-04-01 09:41:35

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