Attachment Hazard Report

This document pretains to SES-LIC-20110406-00403 for License on a Satellite Earth Station filing.

IBFS_SESLIC2011040600403_880613

                     ANALYSIS OF A NON-IONIZING RADIATION
                     FOR A 1.2 METER EARTH STATION SYSTEM

This report analysis the non-ionozing radiation levels for a 1.2-m earth station system. The
analysis and calculations in this report comply with the methods described in th FCC Office
of Engineering and Technology Bulletin, No.65. 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 seperate 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
explosure. The Maximum Permissible Exposure (MPE) limits for person in a General
Population/Uncontrolled enviroment are shown in Table 1. MPE limits for persons in an
Occupation/Controlled enviromenment are shown in Table 2. The purpose of the analysis of
this report is to determine the power flux density levels and to compare these levels to the
specified MPEs

Table 1 – Limits for General Population/Uncontrolled Exposure
       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 General Occupational/Controlled Exposure (MPE)
       Frequency Range (MHz)               Power Density (mW/cm2
       30-300                                     1.0
       300-1500                                   Frequency (MHz)*(0.8/1200)
       1500-100,000                               5.0

Table 3 – Formulas and Parameters Used for Determining Power Flux Densities
       Parameter                  Value                Units
       Antenna Diameter           1.2                  m
       Antena Surface Area        1,130973355          m2
       Subreflector Diameter      0                    cm
       Area of Subreflector       0                    cm2
       Frequency                  14240                MHz
       Wavelength                 0.02105263           m
       Transmit Power             22                   W
       Antenna Gain (dBi)         43.00                dBi
       Antenna Gain (factor)      19952,62             n/a
       Pi                         3.1415927            n/a
       Antenna Efficiency         0.622229             n/a


1 – Far Field Distance Calculation
       The distance to the beginning of the far field (Rff) and the on-axis power density (Sff)
       are calculated as below

       Rff = 41.040 m
       Sff = 2.074 mW/cm2

2 – Near Field Distance Calculation
       The distance to the end of the Near Field (Rnf) and the maximum power density in the
       Near Field (Snf) are calculated as below

       Rnf = 17.100 m
       Snf = 4.842 mW/cm2

3 – Transition Region Calculation
       The Transit Region is located between Near Field and Far Field Regions. The
       maximum power density in the Transit Region will not exceed that calculated for the
       Near Field region. The power density in the Transit Region (St) at a distance Rt is
       calculated as below

       St = 4.842 mW/cm2 ,

4- Region Between the Main Reflector and Subrefletor
       No Subreflector used in this system.

5- Main Reflector Region
       Power density at the Main reflector Surface Ssurface (Ssurface) is calculated as below

       Ssurface = 7.781 mW/cm2

6- Region Between the main reflector and the Ground
       Power density between the Main Reflector and the Ground (Sg) is calculated as below

       Sg = 0.830 mW/cm2

7- SUMMARY OF CALCULATIONS
      Table 4. Summary of expected Radiation Levels for Uncontrolled Enviroment

                                          Expected
                                          Maximum
                              Distance
               Region                  Radiation Power    Hazard Assesement
                                 (m)
                                        Density Level
                                          mW/cm2
       Far Field (Sff)         41,04        2.074         Potential Hazard
       Near Field (Snf)         17,1        4,842         Potential Hazard
       Transition Region (St)               4.842         Satisfiecs FCC MPE
       Main Reflector
                                           14,147         Potential Hazard
       (Ssurface)
       Between Main
       Reflector & Ground                   3,537         Potential Hazard
       (Sg)


Table 5. Summary of Expected Ration Levels for Controlled Enviroment

                                     Expected
                                     Maximum
                            Distance
     Region                          Radiation Power       Controlled
                            (m)
                                     Density Level
                                     mW/cm2
     Far Field                41,04           2.074        Satisfies FCC MPE
     Near Field                17,1           4,842        Satisfies FCC MPE
     Transition Region                        4.842        Satisfies FCC MPE
     Main Reflector                          14,147        Potential Hazard
     Between Main
                                              3,537        Satisfies FCC MPE
     Reflector & Ground




8. CONCLUSION

Based upon the above analysis it’s concluded that FCC RF Guidelines have been exceeded in
the specific region(s) of Table 4. The applicant proposes to comply with MPE limits of
Uncontrolled and Controlled areas.

The antenna will be installed at the applicants facility on the roof of NPC Building,
Washington DC. Since it’s a roof top with limited access only for the employee of the
Building and Applicant, no general population will be present or near the direct path of main
beam. The applicant will mark the earth station with the standart radiation hazard warnings.

Finally the earth station’s operation personel will not have access to areas that exceeds the
MPE levels, while the earth station is in operation. The transmitter will be turned off during
the periods of maintanance, so that MPE standarts will be complied with for those regions in
close proximity to the main reflector, which could be occupied by operating personnel.



Document Created: 2009-03-25 10:42:51
Document Modified: 2009-03-25 10:42:51

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