Attachment Exhibit A

This document pretains to SES-MOD-20131108-00956 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2013110800956_1020492

                                                                                        Global Data Systems, Inc.
                                                                                               EXHIBIT A

                                           Radiation Hazard Study

                                                   Vertex 7.2m

This study analyzes the potential Radio Frequency (RF) human exposure levels caused by the Electro Magnetic
(EM) fields of the above-captioned antenna. The mathematical analysis performed below complies with the
methods described in the Federal Communications Commission Office of Engineering and Technology Bulletin
No. 65 (1985 rev. 1997) R&O 96-326.

Maximum Permisible Exposure
There are two separate levels of exposure limits. The first applies to persons in the general population who are
in an uncontrolled environment. The second applies to trained personnel in a controlled environment.
According to 47 C.F.R. § 1.1310, the Maximum Permissible Exposure (MPE) limits for frequencies above 1.5
GHz are as follows:
            • General Population / Uncontrolled Exposure 1.0 mW/cm2
            • Occupational / Controlled Exposure 5.0 mW/cm2
The purpose of this study is to determine the power flux density levels for the earth station under study as
compared with the MPE limits. This comparison is done in each of the following regions:
            1. Far-field region
            2. Near-field region
            3. Transition region
            4. The region between the feed and the antenna surface
            5. The main reflector region
            6. The region between the antenna edge and the ground

Input Parameters
The following input parameters were used in the calculations:

Parameter                                          Value         Unit      Symbol
Atenna Diameter:                                    7.2           m          D
Antenna Transmit Gain:                             58.10         dBi         G
Trasmit Frequency:                                 14250         MHz         f
Feed Flange Diameter:                              104.00        cm          d
Power Input to the Antenna:                        400.00        W           P

Calculated Parameters
The following values were calculated using the above input parameters and the corresponding formulas.

Parameter                                          Value         Unit      Symbol        Formula
                                                                     2                   2
Anenna Surface Area:                               40.72         m            A      πD /4
                                                                      2                 2
Area of Feed Flange:                              8494.87        cm           a      πd /4
                                                                                         2      2   2
Antenna Efficiency:                                 0.56                      η      Gλ /( π D )
                                                                                        G /10
Gain Factor:                                     645654.23                    g      10
Wavelength:                                        0.0211        m            λ      300/ f




                                                      1 of 3


                                                                                         Global Data Systems, Inc.
                                                                                                EXHIBIT A

Behavior of EM Fields as a Function of Distance
The behavior of the characteristics of EM fields varies depending on the distance from the radiating antenna.
These characteristics are analyzed in three primary regions: the near-field region, the far-field region and the
transition region. Of interest also are the region between the antenna main reflector and the subreflector, the
region of the main reflector area and the region between the main reflector and ground.




Figure 1. EM Fields as a Function of Distance

For parabolic aperture antennas with circular cross sections, such as the antenna under study, the near-field, far-
field and transition region distances are calculated as follows:

Parameter                                          Value         Unit    Formula
                                                                                 2
Near Field Distance:                              615.600         m      Rnf = D /(4λ)
Distance to Far Field:                            1477.440        m      Rff = 0.60D2/(λ)
Distance of Trasition Region                      615.600         m      Rt = Rnf

The distance in the transition region is between the near and far fields. Thus, Rnf        ≤ Rt ≤ Rff . However, the
power density in the transition region will not exceed the power density in the near-field. Therefore, for purposes
of the present analysis, the distance of the transition region can equate the distance to the near-field.


Power Flux Density Calculations
The power flux density is considered to be at a maximum through the entire length of the near-field. This region
is contained within a cylindrical volume with a diameter, D, equal to the diameter of the antenna. In the
transition region and the far-field, the power density decreases inversely with the square of the distance. The
following equations are used to calculate power density in these regions.




                                                       2 of 3


                                                                                          Global Data Systems, Inc.
                                                                                                 EXHIBIT A


Parameter                                          Value        Unit       Symbol      Formula
                                                                       2                                 2
Power Density in the Near-Field                    2.198       mW/cm         S nf      16.0 η P /(πD )
                                                                       2                            2
Power Density in the Far-Field                     0.942       mW/cm         S ff      GP /(4π R ff )
                                                                       2
Power Density in the Trans. Region                 2.198       mW/cm          St       Snf R nf /(R t)

The region between the main reflector and the subreflector is confined within a conical shape defined by the
feed assembly. The most common feed assemblies are waveguide flanges. This energy is determined as
follows:

Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density at the Feed Flange                   188.3       mW/cm         S fa      4P / a

The power density in the main reflector is determined similarly to the power density at the feed flange; except
that the area of the reflector is used.

Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density at Main Reflector                    3.930       mW/cm       S surface   4P / A

The power density between the reflector and ground, assuming uniform illumination of the reflector surface, is
calculated as follows:

Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density between Reflector and Ground         0.982       mW/cm         Sg        P /A

Table 1 summarizes the calculated power flux density values for each region. In a controlled environment, the
only regions that exceed FCC limitations are shown below. These regions are only accessible by trained
technicians who, as a matter of procedure, turn off transmit power before performing any work in these areas.


                                                                   Controlled Environment
Power Densities                                  mW/cm2
                                                                          (5 mW/cm2)
Far Field Calculation                              0.942          Satisfies FCC Requirements
Near Field Calculation                             2.198          Satisfies FCC Requirements
Transition Region                                  2.198          Satisfies FCC Requirements
Region between Main and Subreflector               188.3              Exceeds Limitations
Main Reflector Region                              3.930          Satisfies FCC Requirements
Region between Main Reflector and Ground           0.982          Satisfies FCC Requirements
Table 1. Power Flux Density for Each Region

In conclusion, the results show that the antenna, in a controlled environment, and under the proper mitigation
procedures, meets the guidelines specified in 47 C.F.R. § 1.1310.




                                                      3 of 3


                                                                                                Global Data Systems
                                                                                                   EXHIBIT A

                                           Radiation Hazard Study

                                                 ASC Signal 9.4M

This study analyzes the potential Radio Frequency (RF) human exposure levels caused by the Electro Magnetic
(EM) fields of the above-captioned antenna. The mathematical analysis performed below complies with the
methods described in the Federal Communications Commission Office of Engineering and Technology Bulletin
No. 65 (1985 rev. 1997) R&O 96-326.

Maximum Permisible Exposure
There are two separate levels of exposure limits. The first applies to persons in the general population who are
in an uncontrolled environment. The second applies to trained personnel in a controlled environment. According
to 47 C.F.R. § 1.1310, the Maximum Permissible Exposure (MPE) limits for frequencies above 1.5 GHz are as
follows:
            • General Population / Uncontrolled Exposure 1.0 mW/cm2
            • Occupational / Controlled Exposure 5.0 mW/cm2
The purpose of this study is to determine the power flux density levels for the earth station under study as
compared with the MPE limits. This comparison is done in each of the following regions:
            1. Far-field region
            2. Near-field region
            3. Transition region
            4. The region between the feed and the antenna surface
            5. The main reflector region
            6. The region between the antenna edge and the ground


Input Parameters
The following input parameters were used in the calculations:

Parameter                                           Value        Unit       Symbol
Atenna Diameter:                                     9.4          m           D
Antenna Transmit Gain:                              60.90         dBi         G
Trasmit Frequency:                                  14250        MHz          f
Feed Flange Diameter:                               18.42         cm          d
Power Input to the Antenna:                        400.00         W           P

Calculated Parameters
The following values were calculated using the above input parameters and the corresponding formulas.

Parameter                                           Value        Unit       Symbol        Formula
                                                                      2
Anenna Surface Area:                                69.40         m            A      πD 2/4
Area of Feed Flange:                               266.34        cm2           a      πd 2/4
Antenna Efficiency:                                  0.63                      η      Gλ2/( π2D 2)
Gain Factor:                                     1230268.77                    g      10G /10
Wavelength:                                        0.0211         m            λ      300/ f




                                                      1 of 3


                                                                                              Global Data Systems
                                                                                                 EXHIBIT A

Behavior of EM Fields as a Function of Distance
The behavior of the characteristics of EM fields varies depending on the distance from the radiating antenna.
These characteristics are analyzed in three primary regions: the near-field region, the far-field region and the
transition region. Of interest also are the region between the antenna main reflector and the subreflector, the
region of the main reflector area and the region between the main reflector and ground.




Figure 1. EM Fields as a Function of Distance

For parabolic aperture antennas with circular cross sections, such as the antenna under study, the near-field, far-
field and transition region distances are calculated as follows:

Parameter                                           Value         Unit    Formula
Near Field Distance:                              1049.275         m      Rnf = D2/(4λ)
Distance to Far Field:                            2518.260         m      Rff = 0.60D2/(λ)
Distance of Trasition Region                      1049.275         m      Rt = Rnf

The distance in the transition region is between the near and far fields. Thus, Rnf        ≤ Rt ≤ Rff . However, the
power density in the transition region will not exceed the power density in the near-field. Therefore, for purposes
of the present analysis, the distance of the transition region can equate the distance to the near-field.


Power Flux Density Calculations
The power flux density is considered to be at a maximum through the entire length of the near-field. This region
is contained within a cylindrical volume with a diameter, D, equal to the diameter of the antenna. In the transition
region and the far-field, the power density decreases inversely with the square of the distance. The following
equations are used to calculate power density in these regions.




                                                       2 of 3


                                                                                                 Global Data Systems
                                                                                                    EXHIBIT A


Parameter                                           Value        Unit       Symbol      Formula
                                                                        2
Power Density in the Near-Field                     1.442      mW/cm          S nf      16.0 η P /(πD 2)
Power Density in the Far-Field                      0.618      mW/cm2         S ff      GP /(4π R ff2)
Power Density in the Trans. Region                  1.442      mW/cm2          St       Snf R nf /(R t)

The region between the main reflector and the subreflector is confined within a conical shape defined by the feed
assembly. The most common feed assemblies are waveguide flanges. This energy is determined as follows:



Parameter                                           Value        Unit       Symbol      Formula
                                                                        2
Power Density at the Feed Flange                   6007.4      mW/cm          S fa      4P / a

The power density in the main reflector is determined similarly to the power density at the feed flange; except that
the area of the reflector is used.

Parameter                                           Value        Unit       Symbol      Formula
                                                                        2
Power Density at Main Reflector                     2.306      mW/cm        S surface   4P / A

The power density between the reflector and ground, assuming uniform illumination of the reflector surface, is
calculated as follows:

Parameter                                           Value        Unit       Symbol      Formula
                                                                        2
Power Density between Reflector and Ground          0.576      mW/cm          Sg        P /A

Table 1 summarizes the calculated power flux density values for each region. In a controlled environment, the
only regions that exceed FCC limitations are shown below. These regions are only accessible by trained
technicians who, as a matter of procedure, turn off transmit power before performing any work in these areas.


                                                                    Controlled Environment
Power Densities                                   mW/cm2
                                                                           (5 mW/cm2)
Far Field Calculation                              0.618           Satisfies FCC Requirements
Near Field Calculation                             1.442           Satisfies FCC Requirements
Transition Region                                  1.442           Satisfies FCC Requirements
Region between Main and Subreflector               6007.4              Exceeds Limitations
Main Reflector Region                              2.306           Satisfies FCC Requirements
Region between Main Reflector and Ground           0.576           Satisfies FCC Requirements
Table 1. Power Flux Density for Each Region

In conclusion, the results show that the antenna, in a controlled environment, and under the proper mitigation
procedures, meets the guidelines specified in 47 C.F.R. § 1.1310.




                                                      3 of 3


                                                                                           Harris Corporation, Inc.
                                                                                                EXHIBIT A

                                           Radiation Hazard Study

                                                ASC Signal 7.6M

This study analyzes the potential Radio Frequency (RF) human exposure levels caused by the Electro Magnetic
(EM) fields of the above-captioned antenna. The mathematical analysis performed below complies with the
methods described in the Federal Communications Commission Office of Engineering and Technology Bulletin
No. 65 (1985 rev. 1997) R&O 96-326.

Maximum Permisible Exposure
There are two separate levels of exposure limits. The first applies to persons in the general population who are
in an uncontrolled environment. The second applies to trained personnel in a controlled environment.
According to 47 C.F.R. § 1.1310, the Maximum Permissible Exposure (MPE) limits for frequencies above 1.5
GHz are as follows:
            • General Population / Uncontrolled Exposure 1.0 mW/cm2
            • Occupational / Controlled Exposure 5.0 mW/cm2
The purpose of this study is to determine the power flux density levels for the earth station under study as
compared with the MPE limits. This comparison is done in each of the following regions:
            1. Far-field region
            2. Near-field region
            3. Transition region
            4. The region between the feed and the antenna surface
            5. The main reflector region
            6. The region between the antenna edge and the ground


Input Parameters
The following input parameters were used in the calculations:

Parameter                                          Value        Unit       Symbol
Atenna Diameter:                                    7.6          m           D
Antenna Transmit Gain:                             59.40         dBi         G
Trasmit Frequency:                                 14250        MHz          f
Feed Flange Diameter:                              18.42         cm          d
Power Input to the Antenna:                        400.00        W           P

Calculated Parameters
The following values were calculated using the above input parameters and the corresponding formulas.

Parameter                                          Value        Unit       Symbol        Formula
                                                                     2
Anenna Surface Area:                               45.36         m            A      πD 2/4
Area of Feed Flange:                               266.34       cm2           a      πd 2/4
Antenna Efficiency:                                 0.68                      η      Gλ2/( π2D 2)
Gain Factor:                                     870963.59                    g      10G /10
Wavelength:                                        0.0211        m            λ      300/ f




                                                      1 of 3


                                                                                            Harris Corporation, Inc.
                                                                                                 EXHIBIT A

Behavior of EM Fields as a Function of Distance
The behavior of the characteristics of EM fields varies depending on the distance from the radiating antenna.
These characteristics are analyzed in three primary regions: the near-field region, the far-field region and the
transition region. Of interest also are the region between the antenna main reflector and the subreflector, the
region of the main reflector area and the region between the main reflector and ground.




Figure 1. EM Fields as a Function of Distance

For parabolic aperture antennas with circular cross sections, such as the antenna under study, the near-field, far-
field and transition region distances are calculated as follows:

Parameter                                          Value         Unit    Formula
Near Field Distance:                              685.900         m      Rnf = D2/(4λ)
Distance to Far Field:                            1646.160        m      Rff = 0.60D2/(λ)
Distance of Trasition Region                      685.900         m      Rt = Rnf

The distance in the transition region is between the near and far fields. Thus, Rnf        ≤ Rt ≤ Rff . However, the
power density in the transition region will not exceed the power density in the near-field. Therefore, for purposes
of the present analysis, the distance of the transition region can equate the distance to the near-field.


Power Flux Density Calculations
The power flux density is considered to be at a maximum through the entire length of the near-field. This region
is contained within a cylindrical volume with a diameter, D, equal to the diameter of the antenna. In the
transition region and the far-field, the power density decreases inversely with the square of the distance. The
following equations are used to calculate power density in these regions.




                                                       2 of 3


                                                                                             Harris Corporation, Inc.
                                                                                                  EXHIBIT A


Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density in the Near-Field                    2.388       mW/cm         S nf      16.0 η P /(πD 2)
Power Density in the Far-Field                     1.023       mW/cm2        S ff      GP /(4π R ff2)
Power Density in the Trans. Region                 2.388       mW/cm2         St       Snf R nf /(R t)

The region between the main reflector and the subreflector is confined within a conical shape defined by the
feed assembly. The most common feed assemblies are waveguide flanges. This energy is determined as
follows:

Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density at the Feed Flange                  6007.4       mW/cm         S fa      4P / a

The power density in the main reflector is determined similarly to the power density at the feed flange; except
that the area of the reflector is used.

Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density at Main Reflector                    3.527       mW/cm       S surface   4P / A

The power density between the reflector and ground, assuming uniform illumination of the reflector surface, is
calculated as follows:

Parameter                                          Value        Unit       Symbol      Formula
                                                                       2
Power Density between Reflector and Ground         0.882       mW/cm         Sg        P /A

Table 1 summarizes the calculated power flux density values for each region. In a controlled environment, the
only regions that exceed FCC limitations are shown below. These regions are only accessible by trained
technicians who, as a matter of procedure, turn off transmit power before performing any work in these areas.


                                                                   Controlled Environment
Power Densities                                  mW/cm2
                                                                          (5 mW/cm2)
Far Field Calculation                             1.023           Satisfies FCC Requirements
Near Field Calculation                            2.388           Satisfies FCC Requirements
Transition Region                                 2.388           Satisfies FCC Requirements
Region between Main and Subreflector              6007.4              Exceeds Limitations
Main Reflector Region                             3.527           Satisfies FCC Requirements
Region between Main Reflector and Ground          0.882           Satisfies FCC Requirements
Table 1. Power Flux Density for Each Region

In conclusion, the results show that the antenna, in a controlled environment, and under the proper mitigation
procedures, meets the guidelines specified in 47 C.F.R. § 1.1310.




                                                      3 of 3



Document Created: 2013-11-07 10:20:46
Document Modified: 2013-11-07 10:20:46

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