Attachment Exhibit C

This document pretains to SES-LIC-20160317-00255 for License on a Satellite Earth Station filing.


                                                                                            Exhibit
Radiation Hazard Report                                                                     Page 1 of 5


      Analysis of Non-Ionizing Radiation for a 2.7-Meter Earth
                          Station System
This report analyzes the non-ionizing radiation levels for a 2.7-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, 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/cm2)
                            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/cm2)
                            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                    2.7              m
     Ant Equiv Surface Area            Asurface          7 elements                 1.4#              m2
     Frequency                           F                  Input                    408              MHz
     Wavelength                          λ                 300 / F                 0.7353             m
     Transmit Power                      P                  Input                  100.00             W
     Antenna Gain (dBi)                 Ges                 Input                   11.5              dBi
     Antenna Gain (factor)               G                 10Ges/10                 14.1              n/a
     Pi                                  π                Constant               3.1415927            n/a
     Antenna Efficiency                  η               Gλ2/(π2D2)                 0.463             n/a

# For a Yagi Antenna with 7 elements the surface area of each element is estimated to be 0.2 m2
 Total surface area is 1.4 m2


                                                                                  Exhibit
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                       Rff = 0.60 D2 / λ                   (1)
                                                                = 5.95 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                 Sff = G P / (4 π Rff 2)             (2)
                                                                = 3.169 W/m2
                                                                = 0.316 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 can be determined from the following equation:

     Extent of the Near Field                               Rnf = D2 / (4 λ)                    (3)
                                                                = 2.5 m

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

     Near Field Power Density                               Snf = 16.0 η P / (π D2)             (4)
                                                                = 7.434 W/m2
                                                                = 0.743 mW/cm2

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 2 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 can be determined from the following
equation:

     Transition Region Power Density                        Stz = Snf*Rnf / Rnf                 (5)
                                                                = 0.464 mW/cm2


Rnf is calculated at a distance of 4 meters from the antenna.


                                                                            Exhibit
Radiation Hazard Report                                                     Page 3 of 5



4.      Region between the Antenna and the Ground

Assuming uniform illumination of the antenna surface, the power density between the antenna and
the ground can be determined from the following equation:

     Power Density between Antenna and Ground           Sg = P / Asurface                 (6)
                                                           = 71.42 W/m2
                                                           = 7.142 mW/cm2


                                                                               Exhibit
Radiation Hazard Report                                                        Page 4 of 5



5.     Summary of Calculations

           Table 4. Summary of Expected Radiation levels for Uncontrolled Environment
                                            Calculated Maximum
                                       Radiation Power Density Level
Region                                              (mW/cm2)               Hazard Assessment
1. Far Field (Rff = 5.9 m)                      Sff        0.316             Potential Hazard
2. Near Field (Rnf = 2.5 m)                     Snf        0.743             Potential Hazard
3. Transition Region (Rnf < Rt < Rff)           St         0.464              Potential Hazard
4. Between Antenna and Ground                   Sg         7.142             Potential Hazard

            Table 5. Summary of Expected Radiation levels for Controlled Environment
                                           Calculated Maximum
                                          Radiation Power Density
Region                                        Level (mW/cm2)               Hazard Assessment
1. Far Field (Rff = 5.9 m)                     Sff         0.316            Satisfies FCC MPE
2. Near Field (Rnf = 2.5 m)                    Snf         0.743            Satisfies FCC MPE
3. Transition Region (Rnf < Rt < Rff)          St          0.464            Satisfies FCC MPE
4. Between Antenna and Ground                  Sg          7.142             Potential Hazard

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



6.     Conclusions

Based upon the above analysis, it is concluded that FCC RF Guidelines have been exceeded in all
fields of the Uncontrolled (Table 4) environment. In the Controlled (Table 5) environments only the
area Between the Antenna and Ground has levels that exceed the FCC RF Guidelines. The
applicant proposes to comply with the Maximum Permissible Exposure (MPE) limits of 0.3
mW/cm**2 for the Uncontrolled Areas, and the MPE limits of 1.5 mW/cm**2 for the Controlled
Areas.

The earth station Yagi antenna will be mounted on a platform; so the applicant agrees that the
antenna is in an area secured from the public and worker personnel not familiar with the earth
station system. Non-assigned worker personnel and the general public must be accompanied by
knowledgeable earth station personnel when they enter the earth station secured area.

The earth station’s secured area will be marked with the required radiation hazard signs as
described in the recent FCC R&0 13-39. The area in the vicinity of the earth station secured area
will also have signs to inform those in the general population and those who may be working in the
area or otherwise present that they are close to a RF System capable of producing hazardous
levels.

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


                                                                                    Exhibit
Radiation Hazard Report                                                             Page 5 of 5

     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.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 worker.



Document Created: 2016-03-09 14:05:34
Document Modified: 2016-03-09 14:05:34

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