Attachment Exhibit C

This document pretains to SES-MOD-20190417-00528 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2019041700528_1656999

                                               ISAT US Inc.

                                          FCC Form 312 Exhibit C

                                        Radiation Hazard Analysis

  I.    Introduction

This Exhibit analyzes the non-ionizing radiation levels for the three Tampa Microwave terminal earth
stations 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 specify 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, and 3) transition region. The analysis also examined the safe distance required to meet both the
controlled and uncontrolled exposure limits. The summary of results and discussion is provided in
Section 2 and the detailed analyses are provided in Section 3.

  II.   Summary of Results

The Tables below summarize the results for the proposed Tampa terminals. The analysis of the non-
ionizing radiation levels, provided in Section 3, assumed the maximum allowed input power to antenna
of 4W 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 4W 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. This is especially true in the case of the Tampa
terminals, as they utilize small, dish antennas that result in a very narrow main beam, resulting in higher
calculated power density in the main beam but a sharp drop off in energy as one moves toward the side
lobes.

The Tampa terminals are for commercial and government use and are not intended to be operated by
the general public. The terminal is cost prohibitive for purchase by the general public, therefore it will
only be operated by trained professional personnel. The antenna installers will be aware of the
antenna’s radiation environment and use measures best suited to maximize protection to anyone who
may come into the proximity of the terminal.


As summarized in the tables below, the Tampa 65 antenna meets the FCC’s MPE levels for uncontrolled
or controlled environments beyond separation distances of about 32.14 m and 14.37 m, respectively.
The Tampa 95 antenna meets the FCC’s MPE levels for uncontrolled or controlled environments beyond
separation distances of about 45.45 m and 20.32m, respectively. The Tampa 130 antenna meets the
FCC’s MPE levels for uncontrolled or controlled environments beyond separation distances of about
84.44 m and 37.76 m, respectively. Based on these calculations, the Tampa 65 antenna meets the FCC’s
MPE levels for controlled environments in the near field, far field and the transition region of the
antenna and exceeds the MPE levels for uncontrolled environments in the near field, far field and the
transition region of the antenna. The Tampa 95 antenna meets the FCC’s MPE levels for controlled
environments in the near field, far field, and transition region, and meets the MPE levels for
uncontrolled environments in the far field region and exceeds the MPE levels for uncontrolled
environments in the near field and transition regions. The Tampa 130 antenna meets the FCC’s MPE
levels for both controlled and uncontrolled environments in the near field, far field and the transition
regions of the antenna. Training of personnel with access to the terminal would include consideration
of the operational modes of the antenna and information on how to prevent radiation exposure,
including disabling the communications system.

Additionally, there are various safety features associated with the operation and installation of the
terminals that will prevent radiation exposure. For example, the terminals are 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 nearly instantaneously and will not resume operating until the signal from the satellite is
reacquired. In fact there is a double shut down protection in the event that someone or something
obstructs the RF path to the satellite. Not only does the terminal automatically turn off its Transmit
capability if it loses the satellite Receive signal, i.e. the transmission path is compromised, but the radio
frequency amplifier is additionally muted via its monitor and control so that no radio frequency can be
transmitted. Especially given the small size of these antennas and their operational elevation angle,
there is a high probability that any person passing close enough to the antenna to be exposed to its
main beam would also block the RF path between the terminal and the satellite triggering the automatic
shutdown mechanism. As a result of this automatic shutdown mechanism, the maximum continuous
time that a person could be exposed to the main beam transmissions at any power level would be
significantly less than one second before the antenna would cease transmitting.

The antenna will be operated only at locations not accessible by the general population. Given that the
antenna will not operate below elevation angles of five degrees, and that the terminal will be pointed
upward toward the satellite - persons are unlikely to be exposed to the main beam of the antenna. Any
areas where the limits for uncontrolled environments could be exceeded will be restricted to trained
personnel. Furthermore, the manuals for these terminals will provide warnings regarding potential for
radiation hazard.

In conclusion, the results of the analysis combined with the design and operational characteristics of the
terminals show that the Tampa terminals, when deployed, and used under the proper mitigation
procedures, meet the guidelines specified in § 1.1310 of the Regulations.




                                                      2


Tampa 65 Terminal
                                Calculated       Limit
                                              Controlled       Limit Uncontrolled
                     Distance     Power
Region                                       Environment          Environment
                       (m)       Density
                                             ≤ 5 mW/cm2           ≤ 1 mW/cm2
                                (mW/cm2)
Safe Range for       ≥32.14        1.0           Meets Limit      Meets Limit
Uncontrolled
Safe Range for       ≥14.37        5.0           Meets Limit     Exceeds Limit
Controlled
Near Field            10.56       2.80           Meets Limit     Exceeds Limit
Far Field             25.35       1.61           Meets Limit     Exceeds Limit
Transition Region     10.56       2.80           Meets Limit     Exceeds Limit




Tampa 95 Terminal
                                Calculated       Limit
                                              Controlled       Limit Uncontrolled
                     Distance     Power
Region                                       Environment          Environment
                       (m)       Density
                                             ≤ 5 mW/cm2           ≤ 1 mW/cm2
                                (mW/cm2)
Safe Range for
                                   1.0           Meets Limit      Meets Limit
Uncontrolled         ≥45.45
Safe Range for
                                   5.0           Meets Limit     Exceeds Limit
Controlled           ≥20.32
Near Field            22.56       1.31           Meets Limit     Exceeds Limit
Far Field             54.15       0.70           Meets Limit      Meets Limit
Transition Region     22.56       1.31           Meets Limit     Exceeds Limit




Tampa 130 Terminal
                                Calculated       Limit
                                              Controlled       Limit Uncontrolled
                     Distance     Power
Region                                       Environment          Environment
                       (m)       Density
                                             ≤ 5 mW/cm2           ≤ 1 mW/cm2
                                (mW/cm2)
Safe Range for
                                   1.0           Meets Limit      Meets Limit
Uncontrolled         ≥84.44
Safe Range for
                                   5.0           Meets Limit     Exceeds Limit
Controlled           ≥37.76
Near Field           42.25        0.70           Meets Limit      Meets Limit
Far Field            101.40       0.69           Meets Limit      Meets Limit
Transition Region    42.25        0.70           Meets Limit      Meets Limit



                                             3


 III.   Detailed Calculations

Tampa 65 Terminal

 Input Parameter                   Value           Units   Symbol
 Antenna Major Axis Dimension               0.65   m       D
 Antenna Transmit Gain @30 GHz             45.11   dBi     G
 Transmit Frequency                        30000   MHz      F
 Power Input to the Antenna                    4   Watts    P

 Antenna Efficiency                         0.58 Real      η

 Calculated Parameter              Value        Units      Symbol   Formula
 Gain Factor                           32433.96 Real       g        10^(G/10)
 Wavelength                                0.01 m          λ        300/f

 Antenna Field Distances
 Calculated Parameter              Value         Units     Symbol   Formula
 Near-Field Distance                       10.56 m         Rnf      D²/(4λ)
 Distance to Far-Field                     25.35 m         Rff      0.6D²/λ
 Distance of Transition Range              10.56 m         Rt       Rt=Rnf

 Power Density
 Calculated Parameter              Value         Units  Symbol      Formula
 Power Density in the Near Field            2.80 mW/cm² Snf         16ηP/(πD²)
 Power Density in the Far Field             1.61 mW/cm² Sff         gP/(4πRff²)
 Power Density in the Transition
 Region                                     2.80 mW/cm² St          Snf*Rnf/Rt



 Distance to 1 mW/cm2                      32.14 m
 Distance to 5 mW/cm2                      14.37 m


Tampa 95 Terminal

 Input Parameter                   Value           Units   Symbol
 Antenna Major Axis Dimension               0.95   m       D
 Antenna Transmit Gain @30 GHz             48.12   dBi     G
 Transmit Frequency                        30000   MHz      F
 Power Input to the Antenna                    4   Watts    P

 Antenna Efficiency                         0.58 Real      η

                                             4


 Calculated Parameter              Value        Units      Symbol   Formula
 Gain Factor                           64863.44 Real       g        10^(G/10)
 Wavelength                                0.01 m          λ        300/f

 Antenna Field Distances
 Calculated Parameter              Value         Units     Symbol   Formula
 Near-Field Distance                       22.56 m         Rnf      D²/(4λ)
 Distance to Far-Field                     54.15 m         Rff      0.6D²/λ
 Distance of Transition Range              22.56 m         Rt       Rt=Rnf

 Power Density
 Calculated Parameter              Value         Units  Symbol      Formula
 Power Density in the Near Field            1.31 mW/cm² Snf         16ηP/(πD²)
 Power Density in the Far Field             0.70 mW/cm² Sff         gP/(4πRff²)
 Power Density in the Transition
 Region                                     1.31 mW/cm² St          Snf*Rnf/Rt


 Distance to 1 mW/cm2                      45.45 m
 Distance to 5 mW/cm2                      20.32 m


Tampa 130 Terminal

 Input Parameter                   Value           Units   Symbol
 Antenna Major Axis Dimension                1.3   m       D
 Antenna Transmit Gain @30 GHz              53.5   dBi     G
 Transmit Frequency                        30000   MHz      F
 Power Input to the Antenna                    4   Watts    P            334.8

 Antenna Efficiency                         0.58 Real      η

 Calculated Parameter              Value        Units      Symbol   Formula
 Gain Factor                          223872.11 Real       g        10^(G/10)
 Wavelength                                0.01 m          λ        300/f

 Antenna Field Distances
 Calculated Parameter              Value          Units    Symbol   Formula
 Near-Field Distance                        42.25 m        Rnf      D²/(4λ)
 Distance to Far-Field                     101.40 m        Rff      0.6D²/λ
 Distance of Transition Range               42.25 m        Rt       Rt=Rnf

 Power Density

                                              5


Calculated Parameter              Value        Units  Symbol   Formula
Power Density in the Near Field           0.70 mW/cm² Snf      16ηP/(πD²)
Power Density in the Far Field            0.69 mW/cm² Sff      gP/(4πRff²)
Power Density in the Transition
Region                                    0.70 mW/cm² St       Snf*Rnf/Rt


Distance to 1 mW/cm2                      84.44 m
Distance to 5 mW/cm2                      37.76 m




                                           6



Document Created: 2019-04-17 11:18:14
Document Modified: 2019-04-17 11:18:14

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