Attachment Exhibit 2 Rad Haz

This document pretains to SES-MOD-20130416-00327 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2013041600327_993397

              Exhibit 2: Radio Frequency Radiation Hazard Compliance Analysis


In compliance with the requirements of 47 C.F.R §1.1310 of the FCC Rules, Inmarsat is submitting an
analysis of the calculated RF radiation levels generated with an assessment of any possible worker or
general public exposure to excessive radiation levels. In order to ensure compliance with the FCC
maximum exposure limits, standard analysis procedures were used in accordance with the FCC’s
guidelines as specified in §1.1310.1

This RF Radiation Hazard Compliance analysis (RFR analysis) is limited in scope to the use of ground
and maritime based satellite dishes using fixed dishes or mobile stabilized Earth Stations on Vessel (ESV)
type antennas. There are three types of antenna installations: large antenna teleport installations, VSAT
fixed installations on ground or locations on offshore oil and gas platforms and mobile stabilized ESV
antennas. Although the construction, design and personnel access control is different for the three types
of antennas, the analysis of the potential hazard for each of these types is identical.

In all of the antenna types, there are common characteristics of antenna gain and antenna design which
require analysis. Under the guidelines of FCC OET Bulletin 65 for satellite dish analysis, the following
antenna radiation areas were analyzed:

As shown in diagram 1, there are three primary areas of radiation with a satellite dish:

The first area is the unfocused energy of the near field which is characterized by a signal strength which
can reach a maximum power density that doesn’t decrease with distance. The distance from the antenna
surface to the edge of the near field is determined through use of the formulas in the OET 65 document 2.
In Ku Band the near field areas extend to the front of the antenna to a distance of 30 or more feet for the
average antenna. This is the area most likely to affect personnel in the vicinity of the antenna and is the
primary focus of the study. Because the power in this area is unfocused, the result of the near field
analysis is based on the maximum power level within that area. 3 Also within the near field is an area of
special interest consisting of the surface of the antenna. The power density at the antenna surface was
calculated based on the OET 65 guidelines. 4

The second area is the far field region where the full gain and directionality pattern is realized for the
antenna. In this area, the signal decreases inversely as a function of the square of the distance. This area
starts typically at a distance of hundreds of feet or more from the surface of the antenna. The far field
radiation is generally directed into sky areas which cannot be easily accessed and this radiation is not as
likely to cause impermissible levels of RFR in personnel areas. In accordance with the guidelines of OET
65, the distance to the closest far field boundary5 and associated power densities within the far field




1
  This document is based on the guidelines and formulas of OST/OET Bulletin Number 65, “Evaluating Compliance
with FCC-Specified Guidelines for Human Exposure to Radiofrequency Radiation.” (OET Bulletin 65
Edition 97-01, August 1997), in compliance with the current FCC rules. This analysis is consistent with rules
adopted, but not yet in effect, in Reassessment of Federal Communications Commission Radiofrequency Exposure
Limits and Policies, ET Docket No. 13-84, First Report and Order, FCC 13-39 (rel. Mar. 29, 2013).
2
  OET Bulletin 65, Reference formula (12), page 27
3
  Id. Reference formula (13), page 28.
4
  Id. Reference formula (11), page 27
5
  Id. Reference formula (16) page 29.
                                                 Page 1 of 8


region 6 were calculated. As an intermediary step to the power density formulas, the antenna dish aperture
efficiency was calculated from manufacturer supplied gain as per formula 14 of the OET document.

The transition region is located between the near field and the far field areas and is characterized as a
semi-focused area where the power density decreases inversely with distance from the antenna. As a
matter of characterizing the worst case scenario, the power density was calculated at the boundary
between the near field and the transition zone and also at the boundary of the transition zone with the far
field area, in accordance with the guidelines of OET 65. 7




                                            Diagram 1


Although the majority of the radiated power is contained within a cylinder extending from the surface of
the antenna dish, an additional area of interest is within locations that are off axis from the main radiation
beam and in areas that may be accessed by personnel. According to the guidelines of OET 65, an
estimation of off-axis far field power density can be made using the antenna minimum sidelobe
performance data as defined under §25.209. 8 In this analysis, the “first cut” calculations are run using the
worst case far field power density to determine if the main beam radiation exceeds the permissible RFR
power density levels. In the event that the main beam exceeds the RFR standards, only then will the
sidelobe radiation pattern be considered for analysis. If the main beam creates less power than the
maximum permissible exposure level, it is known that the sidelobe radiation will be less than the main
beam and sidelobe radiation will therefore be compliant as well.




6
  Id. Reference formula (18), page 29.
7
  Id. Reference formula (17), page 29.
8
  47 C.F.R §25.209 (a),(2)
                                                 Page 2 of 8


In near field areas close to the antenna dish, the OET 65 guidelines indicate that an assumption can be
made in radial distances extending beyond one antenna diameter from the antenna center point. Within
areas of interest outside this “one antenna diameter” boundary it can be presumed that a reduction of 20
dB or more can be calculated as a basis of RFR hazard protection. The analysis results reflect this
calculation as per the guidelines of the OET 65 document. 9

This analysis calculates the RFR compliance of 6 antennas which are to be deployed as ESV antennas on
static platforms and vessels. In all of the proposed deployments, the analyzed antennas are to be mounted
on elevated pedestals in locations which are on the top of vessel wheelhouses, flying bridges or quarters
areas which are restricted and where only authorized personnel have access. In this environment, the RFR
exposure limits are indicated to be the Occupational / Controlled Exposure levels. The maximum
permissible exposure levels are to not exceed 5 mW/cm^2.

Applying the methods provided in OET 65, using the proposed maximum BUC power specified for these
dishes as a worst case, the results are as follows:

Calculations:

Power density at reflector surface:       S = 4P/A

Calculated antenna efficiency: ɳ = (Gλ^2/4π)/(πD^2)

Maximum power density within near field:          Snf = 16ɳP/πD^2

Maximum power density at transition zone boundary with far field:         Sff = P*G/4πR^2

Distance to boundary of transition zone with far field:   Rff = 0.6 D^2/λ

Power density within the transition region:       St = Snf*Rnf/R

Where:

ɳ = Aperture efficiency.

G = Power gain in direction of interest (isotropic).

λ= Wavelength (cm).

D = Antenna diameter (cm).

P = Power fed to the antenna.

A = Physical area of antenna (cm^2).

Rnf = Extent of near field from antenna surface, Rff = Extent of far field from antenna surface.

Snf = Power density at near field extent distance, Sff = Power density at far field extent distance.

S = Power density at surface.

9
    Ibid. Page 30.
                                                 Page 3 of 8


R = Distance to the point of interest.


For the Intellian V60 antenna, using the maximum proposed power and bandwidth:

                                               Summary:
                      Dish Model:                                             Intellian V60
                  Transmit Frequency                         14.25      GHz
                     Flange power                            3.03      Watts
                   Antenna Diameter                           0.6     Meters
                     Antenna Gain                            38.1       dBi
                       Efficiency                        80.54%      Calculated
          Power Density at Reflector Surface                 4.287   mW/cm ^2         Result: Within Limits
      Maximum Power Density Within Near Field                3.45    mW/cm ^2         Result: Within Limits
         Distance to Edge of Near Field                      4.28     Meters
Maximum Power Density at Transition Zone Boundary
                                                             1.44    mW/cm ^2         Result: Within Limits
                 with Far Field

Distance to Boundary of Transition Zone with Far Field       10.26    Meters

Power Density at 1 Diameter Distance from Center of
                                                          0.0345     mW/cm ^2         Result: Within Limits
                       Dish.


Compliance Statement:

This antenna is proposed to be used as described on page 3 in an area which has restricted access and only
accessible to authorized personnel. This proposed antenna installation fully complies with the
occupational RF radiation hazard limits, according to the summary of calculations above.

For the Intellian V80 antenna, using the maximum proposed power and bandwidth:

                                               Summary:
                      Dish Model:                                             Intellian V80
                  Transmit Frequency                         14.25      GHz
                     Flange power                             5        Watts
                   Antenna Diameter                          0.83     Meters
                     Antenna Gain                            39.5       dBi
                       Efficiency                        58.10%      Calculated
          Power Density at Reflector Surface                 3.696   mW/cm ^2         Result: Within Limits
      Maximum Power Density Within Near Field                2.15    mW/cm ^2         Result: Within Limits
         Distance to Edge of Near Field                      8.18     Meters
Maximum Power Density at Transition Zone Boundary
                                                             0.89    mW/cm ^2         Result: Within Limits
                 with Far Field

Distance to Boundary of Transition Zone with Far Field       19.63    Meters


                                               Page 4 of 8


Power Density at 1 Diameter Distance from Center of
                                                            0.0215    mW/cm ^2          Result: Within Limits
                       Dish.


Compliance Statement:

This antenna is proposed to be used as described on page 3 in an area which has restricted access and only
accessible to authorized personnel. This proposed antenna installation fully complies with the
occupational RF radiation hazard limits, according to the summary of calculations above.

For the Intellian V110 antenna, using the maximum proposed power and bandwidth:

                                                 Summary:
                     Dish Model:                                              Intellian V110
                 Transmit Frequency                        14.25        GHz
                    Flange power                           12.35       Watts
                 Antenna Diameter                          1.05       Meters
                    Antenna Gain                           41.7         dBi
                      Efficiency                         60.25%      Calculated
         Power Density at Reflector Surface                5.705     mW/cm ^2        Result: Exceeding Limit
     Maximum Power Density Within Near Field               3.44      mW/cm ^2         Result: Within Limits
           Distance to Edge of Near Field                  13.09      Meters
     Maximum Power Density at Transition Zone
                                                           1.43      mW/cm ^2         Result: Within Limits
               Boundary with Far Field
  Distance to Boundary of Transition Zone with Far
                                                           31.42      Meters
                        Field
 Power Density at 1 Diameter Distance from Center
                                                          0.0344     mW/cm ^2         Result: Within Limits
                      of Dish.


Compliance Statement:

This antenna is proposed to be used as described on page 3 in an area which has restricted access and only
accessible to authorized personnel. This antenna exceeds the occupational standards only at the surface of
the antenna dish reflector, which is completely shielded from public access by a permanently installed
radome. Therefore this radome protects the public from RF radiation exposure. The dish surface area is
restricted from access to all except certified field engineers and technicians who are specifically trained in
RF radiation hazards and are required to disable and lockout any transmitting equipment prior to working
in areas which are subject to occupational RF radiation limitations. This proposed antenna installation
fully complies with the occupational RF radiation hazard limits, according to the summary of calculations
and personnel and area restrictions as described above.



For the Intellian V100 antenna, using the maximum proposed power and bandwidth:

                                                 Summary:
                     Dish Model:                                            Intennial V 100

                                                 Page 5 of 8


                 Transmit Frequency                        14.25          GHz
                    Flange power                           11.11         Watts
                 Antenna Diameter                          1.03         Meters
                    Antenna Gain                           41.3           dBi
                      Efficiency                         57.10%        Calculated
         Power Density at Reflector Surface                5.333       mW/cm ^2       Result: Exceeding Limit
     Maximum Power Density Within Near Field               3.05        mW/cm ^2         Result: Within Limits
           Distance to Edge of Near Field                  12.60        Meters
     Maximum Power Density at Transition Zone
                                                           1.27        mW/cm ^2         Result: Within Limits
               Boundary with Far Field
  Distance to Boundary of Transition Zone with Far
                                                           30.24        Meters
                        Field
 Power Density at 1 Diameter Distance from Center
                                                          0.0305       mW/cm ^2         Result: Within Limits
                      of Dish.


Compliance Statement:

This antenna is proposed to be used as described on page 3 in an area which has restricted access and only
accessible to authorized personnel. This antenna exceeds the occupational standards only at the surface of
the antenna dish reflector, which is completely shielded from public access by a permanently installed
radome. Therefore this radome protects the public from RF radiation exposure. The dish surface area is
restricted from access to all except certified field engineers and technicians who are specifically trained in
RF radiation hazards and are required to disable and lockout any transmitting equipment prior to working
in areas which are subject to occupational RF radiation limitations. This proposed antenna installation
fully complies with the occupational RF radiation hazard limits, according to the summary of calculations
and personnel and area restrictions as described above.

For the Intellian V240 antenna, using the maximum proposed power and bandwidth:

                                                 Summary:
                      Dish Model:                                               Intellian V 240
                  Transmit Frequency                           14.25        GHz
                     Flange power                               8          Watts
                  Antenna Diameter                              2.4       Meters
                     Antenna Gain                              49.1         dBi
                       Efficiency                          63.37%        Calculated
          Power Density at Reflector Surface                   0.707    mW/cm ^2         Result: Within Limits
      Maximum Power Density Within Near Field                  0.45     mW/cm ^2         Result: Within Limits
         Distance to Edge of Near Field                        68.40      Meters
Maximum Power Density at Transition Zone Boundary
                                                               0.19     mW/cm ^2         Result: Within Limits
                 with Far Field
Distance to Boundary of Transition Zone with Far Field      164.16        Meters

Power Density at 1 Diameter Distance from Center of
                                                            0.0045      mW/cm ^2         Result: Within Limits
                       Dish.
                                                 Page 6 of 8


Compliance Statement:

This antenna is proposed to be used as described on page 3 in an area which has restricted access and only
accessible to authorized personnel. This proposed antenna installation fully complies with the
occupational RF radiation hazard limits, according to the summary of calculations above.

For the Seatel 4010 antenna, using the maximum proposed power and bandwidth:

                                                  Summary:
                       Dish Model:                                               Seatel 4010
                   Transmit Frequency                          14.25       GHz
                      Flange power                             12.07      Watts
                   Antenna Diameter                              1       Meters
                      Antenna Gain                              40.6       dBi
                        Efficiency                             51.56%   Calculated
           Power Density at Reflector Surface                  6.147    mW/cm ^2      Result: Exceeding Limit
       Maximum Power Density Within Near Field                  3.17    mW/cm ^2        Result: Within Limits
          Distance to Edge of Near Field                       11.88     Meters
 Maximum Power Density at Transition Zone Boundary
                                                                1.32    mW/cm ^2        Result: Within Limits
                  with Far Field

 Distance to Boundary of Transition Zone with Far Field        28.50     Meters

 Power Density at 1 Diameter Distance from Center of
                                                               0.0317   mW/cm ^2        Result: Within Limits
                        Dish.


This antenna is proposed to be used as described on page 3 in an area which has restricted access and only
accessible to authorized personnel. This antenna exceeds the occupational standards only at the surface of
the antenna dish reflector, which is completely shielded from public access by a permanently installed
radome. Therefore this radome protects the public from RF radiation exposure. The dish surface area is
restricted from access to all except certified field engineers and technicians who are specifically trained in
RF radiation hazards and are required to disable and lockout any transmitting equipment prior to working
in areas which are subject to occupational RF radiation limitations. This proposed antenna installation
fully complies with the occupational RF radiation hazard limits, according to the summary of calculations
and personnel and area restrictions as described above.



Summary:

According to the calculations presented within this analysis and the access and personnel restrictions as
described in the RF radiation analysis, the proposed antennas comply with the FCC’s RF radiation
guidelines as described in OET Bulletin 65, “Evaluating Compliance with FCC-Specified Guidelines for
Human Exposure to Radiofrequency Radiation”.

Submitted April 16, 2013

                                                 Page 7 of 8


/Robert W. Fisher/

Robert W. Fisher
Principal Solutions Development Engineer | FSS/MW
Inmarsat
1201 Louisiana St. Suite 2700
Houston, TX, 77002
USA




                                           Page 8 of 8



Document Created: 2013-04-16 13:28:18
Document Modified: 2013-04-16 13:28:18

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