Attachment Exhibit A

This document pretains to SES-MOD-20181030-03713 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2018103003713_1562128

        Exhibit B

Radiation Hazard Analysis


                                                   GCI Anchorage BP 9.0m Radiation Hazard Study



                                                ANALYSIS OF NON-IONIZING RADIATION
                               FOR THE GCI C-BAND 9.0M EARTH STATION ANTENNA IN ANCHORAGE, ALASKA
                                                        Completed 10/24/2018

This report analyzes the non-ionizing radiation levels for the GCI 9.0m C-band earth station antenna employed at the Anchorage, Alaska
(Anchorage BP) site. The analysis and calculations performed in this report comply with the methods described in the FCC Office of
Engineering and Technology Bulletin, No. 65 entitled "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency
Electromagnetic Fields" - first published in 1985 and revised in 1997 in Edition 97-01. Bulletin No. 65 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 teh 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, below. The General Population/Uncontrolled MPE is a function of the transmit frequency and is for an exposure period of
thirty (30) minutes or less. The MPE limits for persons in an Occupational/Controlled environment are shown in Table 2, below. The
Occupational/Controlled MPE is a function of the transmit frequency and is for an exposure period of six (6) minutes or less. The purpose of
the analysis described in this report is to determine the power flux density levels of the earth station ni the far-field, near-field, transition
region, between the subreflector or feed and the main reflector surface, and at the main reflector surface and to compare these levels to the
specified MPE limits.


                       Table 1. Limits for General Population/Uncontrolled Exposure (MPE)
                     Frequency Range (MHz)                                Power Density(mW/cm2)
                            30-300                                                  0.2
                           300-1500                                        Frequency (MHz)/1500
                         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)/300
                         1500-100,000                                               5.0

The following parameters were used to calculate the various power flux densities for this earth station:

           Location:                                  Anchorage, Alaska
           Latitude:                                   61.192575 °N
           Longitude:                                 149.862936 °W
           Operating Frequency:                          6000    MHz
           Wavelength (λ)                               0.04997 meters
           Antenna Diameter (D):                          9.00   meters
           Antenna Area (A):                             63.62   meters²
           Transmit Antenna Gain:                         53.5   dBi
           Transmit Antenna Gain (G):                  223872.1 numeric
           Maximum 5° Off Axis Gain:                      11.5   dBi
           Maximum 5° Off Axis Gain (G5°):                14.2   numeric
           Antenna Efficiency (ƞ):                       0.699   numeric
           Feed Power (P):                                800    Watts


1. Antenna/Main Reflector Surface Calculation
The power density in the main reflector region can be estimated by:
                                                                     Antenna Diameter
                                                            9.00   meters
   Power Density at Reflector Surface,       Ssurface = 4P/A
                                             Ssurface =    50.30   W/m²
                                             Ssurface =    5.03    mW/cm²
   Ssurface = maximum power density at antenna surface
         P = power fed to the antenna
         A = physical area of the antenna
2. Near Field Calculations
In the near field region, of the main beam, the power density can reach a maximum before it begins to decrease with distance.
The magnitude of the on axis (main beam) power density varies according to location in the near-field.
The distance to the end of the near field can be determined by the following equation:


                                                                                                                                       Page 1 of 3


                                                        GCI Anchorage BP 9.0m Radiation Hazard Study

                                                                          Antenna Diameter
                                                              9.00      meters
                       Extent of Near Field,         Rnf = D²/4(λ)
                                                     Rnf = 405.28       meters
       Rnf = extent of near field
        D = maximum dimension of antenna (diameter if circular)
        λ = wavelength
The maximum near-field, on-axis, power density is determined by:
                                                                          Antenna Diameter
                                                               9.00     meters
    On Axis Near Field Power Density,                Snf = 16ƞP/πD²
                                                     Snf =    35.17     W/m²
                                                     Snf =    3.52      mW/cm²
The maximum near-field, 5° off-axis, power density is determined by:
                                                                          Antenna Diameter
                                                                9.00    meters
                Power Density at 5° Off Axis        Snf 5°= (Snf/G)*G5°
                                                    Snf 5°= 0.0002 mW/cm²
       Snf=     maximum near-field power density
     Snf 5° =   maximum near-field power density (5° off axis)
         ƞ=     aperture efficiency
         P=     power fed to antenna
        D=      maximum dimension of antenna (diameter if circular)

3. Far Field Calculations

The power density in the far-field region decreases inversely with the square of the distance.

The distance to the beginning of the far field region can be found by the following equation:

                                                                          Antenna Diameter
                                                               9.00     meters
       Distance to the Far Field Region,             Rff = 0.6D²/λ
                                                     Rff = 972.67       meters

       Rff = distance to beginning of far field
        D = maximum dimension of antenna (diameter if circular)
        λ = wavelength

The maximum main beam power density in the far field can be calculated as follows:
                                                                            Antenna Diameter
                                                                 9.00    meters
On-Axis Power Density in the Far Field,               Sff = (P)(G)/4π(Rff)2
                                                      Sff =     15.06    W/m²
                                                      Sff =     1.51     mW/cm²
The maximum far-field, 5° off-axis, power density is determined by:
                                                                          Antenna Diameter
                                                                9.00    meters
                Power Density at 5° Off Axis        Sff 5°= (Sff/G)*G5°
                                                    Sff 5°= 0.0001 mW/cm²
        Sff=    power density (on axis)
     Sff 5°=    power density (5° off axis)
         P=     power fed to antenna
         G=     power gain of antenna in the direction of interest relative to an isotropic radiator
      Rff =     distance to beginning of far field




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                                                     GCI Anchorage BP 9.0m Radiation Hazard Study

4. Transition Region Calculations

The transition region is located between the near and far field regions. The power density decreases inversely with distance in the transition
region, while 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 in the near field region, as shown above will not
exceed:
                                                                           Antenna Diameter
                                                               9.00      meters
                                                   St=    (Snf*Rnf)/R
                                                St 5° =   (Snf 5°*Rnf)/R
                                                   St=         3.52      mW/cm²
                                                St 5° =      0.0002 mW/cm²

                                                                       Table 3
                                                Summary of Expected Radiation Levels
                                          Calculated Maximum Distance to                       Maximum Permissible Exposure (MPE)
Region                                  Radiation Level (mW/cm² Region (m)                     Occupational       General Population
9.0m Earth Station Antenna
 1. Antenna Surface                           Ssurface=   5.03                                Potential Hazard        Potential Hazard
 2. Near Field                                     Snf=   3.52           405.3                 Satisfies MPE          Potential Hazard
 3. Far Field                                      Sff=   1.51           972.7                 Satisfies MPE          Potential Hazard
 4. Transition Region                               St=   3.52                                 Satisfies MPE          Potential Hazard
 5. Near Field 5° Off Axis                      Snf 5°=   0.0002                               Satisfies MPE           Satisfies MPE
 6. Far Field 5° Off Axis                       Sff 5°=   0.00                                 Satisfies MPE           Satisfies MPE
 7. Transition Region 5° Off Axis               St 5° =   0.0002                               Satisfies MPE           Satisfies MPE


7. Conclusions
Based on the above analysis, it is concluded that the OET/FCC Radiofrequency Electromagnetic Fields guidelines for Maximum Permissible
Exposure (MPE) have not been exceeded in any region for this installation. Further, it should be noted that General Population/Uncontrolled
MPE limit is always satisifed at angles 5° off of boresite or greater for all antenna apertures. As these earth station antennas will never be
operated with elevation angles of less than the minimum specified in 47 C.F.R. Ch. 1 §25.205 (namely 5°), then the MPE associated with the
General Population/Uncontrolled limits will always be satisied even if the transmitter is upgraded at a later date to a larger size. GCI will post
appropriate RF Radiation Hazard placards and other signage in the areas near these antennas and/or will restrict access to the antenna by
means of fencing or other appropriate devices. Finally, the transmitter will be disabled during maintenance activities in the areas where the
Occupational MPE is exceeded in order to protect personnel from exposure.




                                                                      Andrew F. Rzeszut (10/24/2018)
                                                                      Senior Staff Engineer
                                                                      GCI Communication Corp.




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Document Created: 2018-10-24 08:36:51
Document Modified: 2018-10-24 08:36:51

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