Attachment Exhibit C

This document pretains to SES-MFS-20160527-00458 for Modification w/ Foreign Satellite (earth station) on a Satellite Earth Station filing.

IBFS_SESMFS2016052700458_1137131

                                            ISAT US Inc. FCC
                                           Form 312 Exhibit C
                                         Radiation Hazard Analysis

1.0 Introduction

This Exhibit analyzes the non-ionizing radiation levels for the ATOM-99 earth station included in this
application. The analysis and calculations performed in this Exhibit 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.

Bulletin No. 65 and the FCC R&O 96-326 specifies two Maximum Permissible Exposure (MPE) limits that
are dependent on the situation in which the exposure takes place and/or the status of the individuals who are
subject to the exposure. These are described below:

• General Population/Uncontrolled environment MPE limit is 1 mW/cm2. The General Population /
Uncontrolled MPE is a function of transmit frequency and is for an exposure period of thirty minutes or less.

• Occupational/Controlled environment MPE limit is 5 mW/cm2. The Occupational MPE is a function of
transmit frequency and is for an exposure period of six minutes or less.

The analysis determined the power flux density levels of the earth station in the 1) far-field, 2) near- field, 3)
transition region, 4) region between the feed and main reflector surface, 5) at the main reflector surface, and
6) between the antenna edge and the ground. The summary of results and discussion is provided in Section 2
and the detailed analyses is provided in Section 3.


Section 2.0 – Summary of Results

The terminal proposed in this application is for commercial and government uses and intended to be operated
by professional personnel. The analysis of the non-ionizing radiation levels provided in Section 3 assumed
the maximum allowed input power to antenna of 5W and a 100% duty cycle resulting in worst case radiation
levels. In a significant number of deployments the terminal duty cycle would be below 100% and the actual
power required would be lower than the 5W maximum resulting in lower radiation levels than those
calculated. As with any directional antenna the maximum level of non-ionizing radiation is in the main beam
of the antenna that is pointed to the satellite. As one moves around the antenna to the side lobes and back
lobes the radiation levels decrease significantly. Thus, the maximum radiation level from an antenna occurs in
a limited area in the direction the antenna is pointed to. The terminal proposed in this application is designed
to cease transmitting if the receive signal from the satellite is blocked, which could be caused by a person
standing in front of the terminal or from other blockage. If the receive signal is blocked, the transmitter is shut
down and will not resume operating until the signal from the satellite is reacquired. This operational feature of
the terminal minimizes the potential for human radiation exposure. The terminals will be turned off prior to
any maintenance being conducted when a person may need to be in close proximity to the feed flange and
main reflector.


The Table below summarize the result for the proposed terminal.

ATOM-99
                                                       Limit Controlled
                                      Calculated         Environment         Limit Uncontrolled
                      Distance
Region
                        (m)
                                    Power Density       ≤ 5 mW/cm2             Environment
                                     (mW/cm2)                                  ≤ 1 mW/cm2

Near Field               19.8           2.31             Meets Limit           Exceeds Limit
Far Field                47.5           0.99             Meets Limit            Meets Limit
Transition Region        19.8           2.31             Meets Limit           Exceeds Limit
Feed Flange              NA            1640.44          Exceeds Limit          Exceeds Limit
Main Reflector           NA             3.21             Meets Limit           Exceeds Limit

As shown the antenna terminal meets the controlled environment limit of ≤ 5 mW/cm2 except at the feed
flange. The feed flange is a very small area of the terminal antenna and it is extremely unlikely that a person
would be near the feed flange or the main reflector while the terminal is in operation. Any blockage of the
signal from the satellite in these areas would cause the terminal to cease transmitting until the blockage is
removed and the signal from the satellite is reacquired. Also, in a controlled environment technicians are
trained and procedures are put in place to ensure that a safe distance is maintained from the antenna while in
operation.

The terminal when operating with maximum input power and a 100% duty cycle varies in meeting the
uncontrolled environment limit of ≤ 1 mW/cm2. As described above, the maximum radiation levels occur in a
limited area in the direction the antenna is pointed. The automatic shut off capability of the terminal when the
satellite receive signal is blocked will reduce potential human exposure. In addition, the terminal proposed in
this application is for commercial and government use and, given the price points, are not intended to be used
by consumers or widely deployed for use by the general public. Personnel operating these terminals will be
trained in how to operate the terminal safely. Furthermore, the manuals for these terminals will explicitly
indicate that precautions, such has not standing in front of the terminal, that are necessary to limit potential
exposure.


 Section 3.0 – Detailed calculations

Input Parameter                                Value      Units    Symbol
Antenna Diameter                                0.89      m        D
Antenna Transmit Gain                           47.5      dBi      G
Transmit Frequency                             30000      MHz      f
Antenna Feed Flange Diameter                    3.94      cm       d
Power Input to the Antenna                       5        Watts    P

Calculated Parameters
Calculated Parameter                           Value      Units    Symbol     Formula
Antenna Surface Area                           0.6221     m²       A          πD²/4
Area of Antenna Flange                        12.1918     cm²      a          πd²/4
Antenna Efficiency                             0.7194     real     η          gλ²/(π²D²)
Gain Factor                                  56234.1325   real     g          10^(G/10)
Wavelength                                     0.0100     m        λ          300/f

Antenna Field Definitions
Calculated Parameter                           Value      Units    Symbol     Formula
Near-Field Distance                           19.8025     m        Rnf        D²/(4λ)
Distance to Far-Field                          47.526     m        Rff        0.6D²/λ
Distance of Transition Range                  19.8025     m        Rt         Rt=Rnf

Power Flux Density
Calculated Parameter                           Value      Units    Symbol     Formula
Power Density in the Near Field                2.3127     mW/cm²   Snf        16ηP/(πD²)
Power Density in the Far Field                 0.9906     mW/cm²   Sff        gP/(4πRff²)
Power Density in the Transition Region         2.3127     mW/cm²   St         Snf*Rnf/Rt

Flange Power Density
Calculated Parameter                           Value      Units    Symbol     Formula
Power Density at the Feed Flange             1640.4405    mW/cm²   Sfa        4P/a

Main Reflector Power Density
Calculated Parameter                           Value      Units    Symbol     Formula
Power Density at Main Reflector                3.2149     mW/cm²   Ssurface   4P/A



Main Reflector Power Density
Calculated Parameter                           Value      Units    Symbol     Formula
Power Density between Reflector and Ground     0.8037     mW/cm²   Sg         P/A



Document Created: 2016-05-27 10:13:37
Document Modified: 2016-05-27 10:13:37

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