Attachment Exhibit B

This document pretains to SES-MFS-20100618-00714 for Modification w/ Foreign Satellite (earth station) on a Satellite Earth Station filing.

IBFS_SESMFS2010061800714_821195

                                                                                     EXHIBIT B
                                                                          ABS-CBN International
                                                                          Radiation Hazard Study
                                                                              9.0 meter Ku-Band




                            INTRODUCTION
The FCC adopted new guidelines and procedures in 1996 for evaluating environmental effects of
radio frequency (RF) emissions. In order to provide assistance in determining whether proposed
or existing transmitting facilities comply with the new guidelines, the FCC Office of Engineering
and Technology revised OET Bulletin 65. The revised version updates limits for Maximum
Permissible Exposure (MPE) in terms of electric and magnetic field strength and power density
for transmitters operating at frequencies between 300 kHz and 100 GHz. This bulletin was
adopted by the FCC in their General Docket No. 97-303 on August 25, 1997. In order to comply
with the requirements of the Report and Order, calculations to determine the power flux densities
in the far field, near field, and reflector regions of the earth station antenna have been made and
are contained in this study.

The FCC guidelines incorporate two separate tiers of exposure limits that are dependent on the
situation in which the exposure takes place and the status of the individuals who are subject to
exposure. The earth station transmitting equipment and antenna are located within a fenced area
and not accessible to the general public. Entry is restricted to employees who have been made
fully aware of the potential for human exposure and can exercise control over their exposure.
Therefore occupational / controlled exposure maximum power density limits are used in this
study.

The FCC Office of Engineering and Technology suggests a method for calculating the maximum
values of the power densities emanating from an aperture antenna in OET bulletin 65. This
method is used to determine the power densities associated with this satellite antenna.

The ABS-CBN International Richmond, CA Ku-Band satellite earth station will be equipped
with amplifiers having a maximum flange output of 630 watts. The transmitter will feed a 9.0
meter antenna via a transmission link having 1.0 dB loss. The following calculations will be
based on a maximum output power at the antenna flange of 500 watts:


Antenna Surface. The maximum power density directly in front of the antenna may be
expressed as:
                                    4P
                        S surface =
                                     A

                   where:     S surface = maximum power density at the antenna surface
                                     P = power fed to the antenna
                                     A = physical area of the aperture antenna



                                                1


                                                                                   EXHIBIT B
                                                                        ABS-CBN International
                                                                        Radiation Hazard Study
                                                                            9.0 meter Ku-Band



   Using the parameters for this antenna:

              S surface = 4 ( 500 Watts) / π ( 9.0 meters / 2) 2
              S surface = 2000 Watts / 63.6 m 2
              S surface = 31.45 Watts / m 2
              S surface = 3.1 mW / cm 2


Near- Field Region. In the near field of the main beam the power density can reach a maximum
before it begins to decrease with distance. The extent of the near field can be described by the
following equation:

                                                      D2
                                              Rnf   =
                                                      4λ

                where: Rnf = extent of near field
                       D = maximum diameter
                       λ = wavelength

   Using the parameters for this antenna:

                λ =     0.02 meters @ 14500 MHz
               Rnf                    2
                   =    ( 9.0 meters) / 4( 0.02 meters)
               Rnf
                   =    81.0 / .08 meters
               Rnf
                   =    1013    meters

The magnitude of the on axis power density varies according to location in the near field.
However, the maximum value of the near field, on axis, power density can be expressed by the
following equation:


                                                       16ηP
                                              S nf =
                                                       πD 2

       where: S nf = maximum near field power density
                η = aperture efficiency
                P = power fed to the antenna
                D = antenna diameter

                                                    2


                                                                                        EXHIBIT B
                                                                             ABS-CBN International
                                                                             Radiation Hazard Study
                                                                                 9.0 meter Ku-Band




        Using the parameters for this antenna:

               η = 0.5775
               P =      500 Watts
               S nf                                                2
                    =   16 (0.5775) (500 Watts) / π (9.0 meters)
               S nf                                       2
                    =   4620 Watts / 254.5 meter
               S nf                              2
                    =   18.2 Watts /     meter
               S nf
                    =   1.8 mW / cm 2



Far Field Region. For purposes of evaluating RF exposure, the distance to the beginning of the
far field region can be approximated by the following equation:


                                                      0 .6 D 2
                                             R ff =
                                                          λ

              where: R ff = distance to the beginning of far field
                     D = diameter of antenna
                     λ = wavelength

              Using the parameters for this antenna:
                                             2
                     R ff = 0.6 (9.0 meters) / .02 meters
                        R ff = 2430 meters

The power density in the far field region of the antenna pattern decreases inversely as the square
of the distance. The power density in the far field region of the radiation pattern can be estimated
by the equation:

                                            S ff = PG / 4πR 2

               where: S ff   =   power density (on axis)
                      P      =   power fed to antenna
                      G      =   power gain of the antenna in the direction of interest
                      R      =   distance to the point of interest


                                                      3


                                                                                  EXHIBIT B
                                                                       ABS-CBN International
                                                                       Radiation Hazard Study
                                                                           9.0 meter Ku-Band




        Using the parameters for this antenna:

                 S ff = 500 Watts (60.1 dBi) / 4 (π) (1013) 2
                 S ff = 511646496 / 12895220
                                             2
                 S ff = 39.7 Watts / meter
                 S ff = 4.0 mW / cm 2




                                   Feed - Main Reflector Region


The RF energy radiated from the feed system is confined to a conical shape whose vertex is
located at the feed and extends outward to the sub-reflector and is directed back to the main
reflector surface. The power density at any point in this region is expressed by the equation:

                                                 S feed = P/A

 Where :
           A = Cross section area of the conical region in meter²
           P = Radiated transmitted power in watts

At the sub-reflector surface the power density is:

         S feed = P / A = 500 / π (0.48 / 2 )² = 2763.1 Watts/meter²
         S feed = 276.3 mW/cm²




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                                                                                    EXHIBIT B
                                                                         ABS-CBN International
                                                                         Radiation Hazard Study
                                                                             9.0 meter Ku-Band



                                  Conclusion
The results of the above calculations are summarized in the following table and illustrated in
Figure 1.


             Region                                  Power Density             Remarks


       Antenna Surface                                3.1 mW/cm²                Non-hazardous

       Feed - Main Reflector Region                 276.3 mW/cm²                Hazardous

       Near Field < 1013 meters                       1.8 mW/cm²                Non-hazardous

       Far Field      > 2430 meters                   4.0 mW/cm²                Non-hazardous



Results of this hazard study indicate that the 5 mW/cm² MPE limit for Occupational/Controlled
Exposure in the 1500 – 100,000 MHz range is not exceeded in areas directly in front of the
antenna in the near field, in the far field and at the antenna surface, but only in the region
between the sub reflector and the feed horn. This area will not be readily accessible to personnel
and whenever personnel are required to work on the radiating or reflecting parts of the antenna
structure, or within the hazardous zone, the transmitter(s) will be turned off.

Based on this study of predicted radio frequency levels, it is concluded that operation of this
satellite earth station meets OET Bulletin 65 maximum permissible exposure limits and that no
harmful effects will occur to station personnel or anyone within proximity of the station.

Therefore, in accordance with 47 CFR § 1.1307 (b) of the Commission's Rules, preparation and
submission of an Environmental Assessment (EA) is not required.




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               EXHIBIT B
    ABS-CBN International
    Radiation Hazard Study
        9.0 meter Ku-Band




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Document Created: 2010-06-01 15:51:07
Document Modified: 2010-06-01 15:51:07

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