Attachment UHS & S-band RadHaz

This document pretains to SES-LIC-20181224-03650 for License on a Satellite Earth Station filing.

IBFS_SESLIC2018122403650_1593683

Radiation Hazard Report                                                             Exhibit 1 - UHF RadHaz
                                                                                                 Page 1 of 4

 Analysis of Non-Ionizing Radiation for a 3.05-Meter Yagi Antenna Earth Station
                                     System

This report analyzes the non-ionizing radiation levels for a 3.05-meter Yagi antenna earth station
system. The analysis and calculations performed in this report comply with the methods described in
the FCC Office of Engineering and Technology’s General RF Exposure Guidance, 447498 D01 v05r02.
The radiation safety limits used in the analysis are in conformance with Title 47 Chapter I, Subchapter
A, Part 1, Subpart I, Section 1.1310. Section 1.1310 specifies that there are two separate tiers of
exposure 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. 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)
                                 0.3 - 1.34                           100
                                 1.34 - 30                   180/Frequency(MHz)^2
                                  30-300                              0.2
                                 300-1500                    Frequency(MHz)/1500
                               1500-100,000                            1


                      Table 2. Limits for Occupational/Controlled Exposure (MPE)

                          Frequency Range (MHz)             Power Density (mW/cm2)
                                  0.3-3.0                             100
                                  3.0-30                     900/Frequency(MHz)^2
                                  30-300                               1
                                 300-1500                     Frequency(MHz)/300
                               1500-100,000                            5


Radiation Hazard Report                                                      Exhibit 1 - UHF RadHaz
                                                                                          Page 2 of 4
            Table 3. Formulas and Parameters Used for Determining Power Flux Densities

 Parameter                      Symbol       Formula              Value            Units
 Ant Largest Dimension             D           Input              3.048              m
 Frequency                          F          Input              450.2            MHz
 Wavelength                        𝜆          300/F             0.665910             m
 Transmit Power                    P           Input                20              W
 Antenna Gain (dBi)               Ges          Input                16              dBi
 Antenna Gain (factor)             G         10Ges /10        39.81071706           n/a
 Pi                                𝜋         Constant         3.141592654           n/a
 Antenna Efficiency                𝜂           Input               0.95             n/a
                                 ASurface     2                 1.478757            m2
 Ant Equiv Surface Area                     Gλ /(4𝜋)/𝜂




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                    R ff = 0.60 D2 /𝜆                 (1)
                                                              = 8.37 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 = GP/(4𝜋R ff 2 )              (2)
                                                             = 0.90 W/m2
                                                             = 0.090 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 surface area 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                            R nf = D2 /(4𝜆)                   (3)
                                                              = 3.49 m


The maximum power density in the Near Field can be determined from the following equation:
     Near Field Power Density                            Snf = 4ηP/Asurface                (4)
                                                             = 51.4 W/m2
                                                             = 5.14 mW/cm2


Radiation Hazard Report                                                             Exhibit 1 - UHF RadHaz
                                                                                                 Page 3 of 4
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 Rtz can be determined from the following equation:
     Transition Region Power Density                     Stz = Snf R nf /R tz                  (5)
                                                             = 5.14 mW/cm2


Rtz is calculated at a distance of 3.49 meters from the antenna, which is the worst-case distance. This is
the edge of the near-field, Rnf.

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)
                                                            = 13.5 W/m2
                                                         = 1.35 mW/cm2


5. Summary of Calculations


             Table 4. Summary of Expected Radiation Levels for Uncontrolled Environment

                                       Calculated Maximum Radiation Power
 Region                                        Density Level (mW/cm2               Hazard Assessment
 Far Field (Rff = 8.37 m)                   Sff                0.090             Satisfies FCC MPE
 Near Field (Rnf = 3.49 m)                  Snf                5.14              Potential Hazard
 Transition Region (Rnf < Rtz < Rff)        Stz                5.14              Potential Hazard
 Between Reflector and Ground               Sg                 1.35              Potential Hazard


               Table 5. Summary of Expected Radiation Levels for Controlled Environment

                                       Calculated Maximum Radiation Power
 Region                                        Density Level (mW/cm2               Hazard Assessment
 Far Field (Rff = 8.37 m)                   Sff                0.090             Satisfies FCC MPE
 Near Field (Rnf = 3.49 m)                  Snf                5.14              Potential Hazard
 Transition Region (Rnf < Rtz < Rff)        Stz                5.14              Potential Hazard
 Between Reflector and Ground               Sg                 1.35              Satisfies FCC MPE


Radiation Hazard Repor                                                               Exhibit 1 - UHF RadHaz
                                                                                                 Page 4 of 4
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 the Near
Field, the Transition Zone, and the region between the Antenna and the Ground of the Uncontrolled
(Table 4) environment. In the Controlled (Table 5) environments, FCC RF Guidelines have been
exceeded in the Near Field, the Transition Zone. 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, using the following methods.
The earth station Yagi antenna will be mounted on a platform on the top of a roof whereby the
antenna will be in an area secured from the public and worker personnel not familiar with the earth
station system. Due to its height above ground, there will be a greater distance between the antenna
and the far-field, and thus workers would need to be performing maintenance on a man-lift in order to
be close enough to the antenna to be in the potentially-hazardous zone. To mitigate hazardous
exposure, the antenna will not transmit during any maintenance.. 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:

       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.


                                                                                      Exhibit 2
Radiation Hazard Report                                                               Page 1 of 5


      Analysis of Non-Ionizing Radiation for a 3.7-Meter Earth
                          Station System
This report analyzes the non-ionizing radiation levels for a 3.7-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, 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/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                   3.7           m
      Antenna Surface Area           Asurface         π D2 / 4                10.75          m2
      Subreflector Diameter           Dsr              Input                  36.5           cm
      Area of Subreflector            Asr             π Dsr 2/4             1046.35          cm2
      Frequency                        F               Input                  2072           MHz
      Wavelength                       λ              300 / F              0.144788          m
      Transmit Power                   P               Input                  50.00          W
      Antenna Gain (dBi)              Ges              Input                  35.0           dBi
      Antenna Gain (factor)            G              10Ges/10               3162.3          n/a
      Pi                               π             Constant              3.1415927         n/a
      Antenna Efficiency               η             Gλ2/(π2D2)               0.49           n/a


                                                                                  Exhibit 2
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)
                                                                = 56.7 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)
                                                                = 3.909 W/m2
                                                                = 0.391 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)
                                                                = 23.6 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)
                                                                = 9.126 W/m2
                                                                = 0.913 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 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 can be determined from the following equation:

   Transition Region Power Density                          St = Snf Rnf / Rt                   (5)
                                                               = 0.913 mW/cm2


                                                                                    Exhibit 2
Radiation Hazard Report                                                         Page 3 of 5

4. Region between the Main Reflector and the Subreflector

Transmissions from the feed assembly are directed toward the subreflector surface, and are
reflected back toward the main reflector. The most common feed assemblies are waveguide flanges,
horns or subreflectors. The energy between the subreflector and the reflector surfaces can be
calculated by determining the power density at the subreflector surface. This can be determined
from the following equation:

   Power Density at the Subreflector                       Ssr = 4000 P / Asr                   (6)
                                                               = 191.141 mW/cm2

5. Main Reflector Region

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

   Power Density at the Main Reflector Surface          Ssurface = 4 P / Asurface               (7)
                                                                 = 18.601 W/m2
                                                                 = 1.860 mW/cm2


6. Region between the Main 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 / Asurface                    (8)
                                                              = 4.650 W/m2
                                                              = 0.465 mW/cm2


                                                                                   Exhibit 2
Radiation Hazard Report                                                            Page 4 of 5

7. Summary of Calculations

           Table 4. Summary of Expected Radiation levels for Uncontrolled Environment
                                            Calculated Maximum
                                          Radiation Power Density                Hazard
 Region                                        Level (mW/cm2)                  Assessment
 1. Far Field (Rff = 56.7 m)                    Sff         0.391          Satisfies FCC MPE
 2. Near Field (Rnf = 23.6 m)                   Snf         0.913          Satisfies FCC MPE
 3. Transition Region (Rnf < Rt < Rff)          St          0.913          Satisfies FCC MPE
 4. Between Main Reflector and                  Ssr      191.141            Potential Hazard
     Subreflector
 5. Main Reflector                              Ssurface    1.860           Potential Hazard
 6. Between Main Reflector and Ground           Sg          0.465          Satisfies FCC MPE

             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 = 56.7 m)                    Sff         0.391           Satisfies FCC MPE
 2. Near Field (Rnf = 23.6 m)                   Snf         0.913           Satisfies FCC MPE
 3. Transition Region (Rnf < Rt < Rff)          St          0.913           Satisfies FCC MPE
 4. Between Main Reflector and                  Ssr      191.141             Potential Hazard
     Subreflector
 5. Main Reflector                              Ssurface    1.860           Satisfies FCC MPE
 6. Between Main Reflector and Ground           Sg          0.465           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.



8. Conclusions

Based on the above analysis it is concluded that the FCC MPE guidelines have been exceeded (or
met) in the regions of Table 4 and 5. The applicant proposes to comply with the MPE limits by one
or more of the following methods.

Radiation hazard signs will be posted while this earth station is in operation.

Due to the remote and secure location of the proposed earth station antenna and elevation of the
antenna by 3.0 meters above the ground, the area of operation around the antenna will be limited
to those that have knowledge of the potential for radiation exposure. The applicant will ensure that
no buildings or other obstacles will be in the areas that exceed the MPE levels.


                                                                                      Exhibit 2
Radiation Hazard Report                                                               Page 5 of 5

Means of Compliance Controlled Areas

The earth station’s operational staff 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

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

       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: 2018-12-24 10:50:08
Document Modified: 2018-12-24 10:50:08

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