Exhibit B

0048-EX-PL-2007 Text Documents

ViaSat, Inc.

2007-02-12ELS_79607

             EXHIBIT B




RADIATION HAZARD ANALYSIS AND REPORT


This exhibit contains a report of the analysis of the radio frequency (RF) hazard present
during the operation of the proposed radio and antenna systems.

Several antenna systems will be examined or tested during the experimental program
period and an analysis on the RF radiation hazard of each of systems has been performed.

The hub facility may use a variety of antennas ranging in size from 7.1 m down to 2.4 m
and power amplifiers from 400 W down to 40 W.

The mobile test antennas will vary in size from 2.4 m down to 0.22 m and will utilize
power amplifiers ranging in size from 25 W down to 4 W

While the radiation hazard analysis for the antennas was conducted using the full output
power of their respective power amplifiers, it should be noted that in actual operation the
output power will typically be reduced by several dB. Furthermore, the units transmit
using a burst access method with varying duty cycles so the average power output is
further reduced.


Analysis of Non-Ionizing Radiation for Earth Station Systems

This report analyzes the non-ionizing radiation levels for a number earth station systems.
The analysis and calculations performed in this report are in compliance with the
methods described in the FCC Office of Engineering and Technology Bulletin No. 65.

Bulletin No. 65 specifies that there are two separate tiers of exposure limits that are
dependant upon the situation in which the exposure takes place and/or the status of the
individuals who are subject to the exposure. The two tiers are General Population /
Uncontrolled environment, and an Occupational / Controlled environment.

The applicable exposure limit for the General Population / Uncontrolled environment at
this frequency of operation is 1 mW/cm2.

The applicable exposure limit for the Occupational / Controlled environment at this
frequency of operation is 5 mW/cm2.

Definition of terms

The terms are used in the formulas here are defined as follows:

Ssurface = maximum power density at the antenna surface
Snf = maximum near-field power density
St = power density in the transition region
Sff = power density (on axis)
Rnf = extent of near-field
Rff = distance to the beginning of the far-field
R = distance to point of interest
P = power fed to the antenna in Watts
A = physical area of the aperture antenna in m2
G = numeric power gain relative to an isotropic radiator
D = diameter of antenna in meters
F = frequency in MHz
λ = wavelength in meters (300/FMHz)
η = aperture efficiency

Antenna Surface. The maximum power density directly in front of an antenna (e.g., at
the antenna surface) can be approximated by the following equation:

Ssurface = (4 * P) / A

        = x.x mW/cm2


Near Field Region. In the near-field or Fresnel region, 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 (D and λ in same units):

Rnf    = D2 / (4 * λ)

       = x.x m

The magnitude of the on-axis (main beam) 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:

Snf    = (16 * η * P) / (π * D2)

       = x.x mW/cm2

Far-Field Region. The power density in the far-field or Fraunhofer region of the
antenna pattern decreases inversely as the square of the distance. The distance to the start
of the far field can be calculated by the following equation:

Rff    = (0.6 * D2) / λ

       = x.x m

The power density at the start of the far-field region of the radiation pattern can be
estimated by the equation:

Sff    = (P * G) / (4 * π * Rff2)

       = x.x mW/cm2

Transition Region. Power density in the transition region decreases inversely with
distance from the antenna, while power density in the far field (Fraunhofer region) of the
antenna decreases inversely with the square of the distance. The transition region will
then be the region extending from Rnf to Rff. If the location of interest falls within this
transition region, the on-axis power density can be determined from the following
equation:

St     = (Snf * Rnf) / R

       = (x.x m * mW/cm2) / R                 where R is the location of interest in meters


Analysis of Non-Ionizing Radiation for a 7.1 m Earth Station System

P = 224.9 Watts
A = 39.6 m2
G = 730665.0
D = 7.1 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 1437.7 m            0.633 mW/cm2                   Satisfies FCC MPE                     Satisfies FCC MPE

Near field (Rnf) = 599.0 m            1.477 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 1.477 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Main Reflector Surface (Ssurface)     2.273 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in a fenced in area with controlled access and will be serviced by trained personnel.
Based on the above analysis it is concluded that harmful radiation levels will not exist in regions normally occupied by the public.
The transmitter will be turned off when the system is being serviced.


Analysis of Non-Ionizing Radiation for a 6.0 m Earth Station System

P = 224.9 Watts
A = 28.3 m2
G = 521799.8
D = 6.0 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 1026.7 m            0.886 mW/cm2                   Satisfies FCC MPE                     Satisfies FCC MPE

Near field (Rnf) = 427.8 m            2.068 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 2.068 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Main Reflector Surface (Ssurface)     3.182 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in a fenced in area with controlled access and will be serviced by trained personnel.
Based on the above analysis it is concluded that harmful radiation levels will not exist in regions normally occupied by the public.
The transmitter will be turned off when the system is being serviced.


Analysis of Non-Ionizing Radiation for a 4.5 m Earth Station System

P = 283.2 Watts
A = 15.9 m2
G = 293512.4
D = 4.5 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 577.5 m             2.128 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Near field (Rnf) = 240.6 m            4.629 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 4.629 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Main Reflector Surface (Ssurface)     7.122 mW/cm2                   Potential Hazard                      Potential Hazard

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in a fenced in area with controlled access and will be serviced by trained personnel.
Based on the above analysis it is concluded that harmful radiation levels will not exist in regions normally occupied by the public.
The transmitter will be turned off when the system is being serviced.


Analysis of Non-Ionizing Radiation for a 3.7 m Earth Station System

P = 88.5 Watts
A = 11.3 m2
G = 209299.7
D = 3.8 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 411.8 m             0.869 mW/cm2                   Satisfies FCC MPE                     Satisfies FCC MPE

Near field (Rnf) = 171.6 m            2.029 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 2.029 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Main Reflector Surface (Ssurface)     3.121 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in an area with controlled access and will be serviced by trained personnel. Based
on the above analysis it is concluded that harmful radiation levels will not exist in regions normally occupied by the public.


Analysis of Non-Ionizing Radiation for a 2.4 m Earth Station System

P = 7.5 Watts
A = 4.5 m2
G = 83488.0
D = 2.4 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 164.3 m             0.186 W/cm2                    Satisfies FCC MPE                     Satisfies FCC MPE

Near field (Rnf) = 68.4 m             0.434 mW/cm2                   Satisfies FCC MPE                     Satisfies FCC MPE

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 0.434 mW/cm2                   Satisfies FCC MPE                     Satisfies FCC MPE

Main Reflector Surface (Ssurface)     0.668 mW/cm2                   Satisfies FCC MPE                     Satisfies FCC MPE

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

Based on the above analysis it is concluded that harmful radiation levels will not exist in regions normally occupied by the public.


Analysis of Non-Ionizing Radiation for a 0.6 m Earth Station System

P = 3.0 Watts
A = 0.28 m2
G = 5218.0
D = 0.6 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 10.3 m              1.161 W/cm2                    Potential Hazard                      Satisfies FCC MPE

Near field (Rnf) = 4.3 m              2.727 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 2.727 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Main Reflector Surface (Ssurface)     4.278 mW/cm2                   Potential Hazard                      Satisfies FCC MPE

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in a controlled environment or mounted on an elevated platform and will be
operated and serviced by trained personnel. Based on the above analysis it is concluded that harmful radiation levels will not exist in
regions normally occupied by the public.


Analysis of Non-Ionizing Radiation for a 0.6 m Earth Station System

P = 14.0 Watts
A = 0.28 m2
G = 5218.0
D = 0.6 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 10.3 m              5.502 W/cm2                    Potential Hazard                      Potential Hazard

Near field (Rnf) = 4.3 m              12.928 mW/cm2                  Potential Hazard                      Potential Hazard

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 12.928 mW/cm2                  Potential Hazard                      Potential Hazard

Main Reflector Surface (Ssurface)     19.889 mW/cm2                  Potential Hazard                      Potential Hazard

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in a controlled environment or mounted on an elevated platform and will be
operated and serviced by trained personnel. Based on the above analysis it is concluded that harmful radiation levels will not exist in
regions normally occupied by the public. The transmitter will be turned off when the system is being serviced.


Analysis of Non-Ionizing Radiation for a 0.3 m Earth Station System

P = 4.5 Watts
A = 0.067 m2
G = 1236.7
D = 0.2921 m
F = 14,250 MHz
λ = 0.021 m
η = 0.65

Summary of expected radiation levels
                                                                     Uncontrolled environment              Controlled environment
Region                        Maximum Power Density                  Hazard Assessment                     Hazard Assessment

Far field (Rff) = 2.4 m               7.395 W/cm2                    Potential Hazard                      Potential Hazard

Near field (Rnf) = 1.0 m              17.257 mW/cm2                  Potential Hazard                      Potential Hazard

Transition region (Rt)
(Rt) = Rnf < Rt < Rff                 17.257 mW/cm2                  Potential Hazard                      Potential Hazard

Main Reflector Surface (Ssurface)     26.55 mW/cm2                   Potential Hazard                      Potential Hazard

Note, power density level in the area between the feed and the reflector surface is greater than the reflector surface and is assumed to
be a potential hazard.

Conclusions

The proposed earth station system will be located in a controlled environment or mounted on an elevated platform and will be
operated and serviced by trained personnel. Based on the above analysis it is concluded that harmful radiation levels will not exist in
regions normally occupied by the public. The transmitter will be turned off when the system is being serviced.


Conclusions

The proposed earth station systems will be located in either controlled or elevated environments with limited access and will only be
operated and serviced by trained personnel. Further, per OET-65, the expected power levels one antenna diameter removed from the
main axis will be 20 dB (100 times) lower than the power in the main antenna beam.

Based on the above analysis it is concluded that harmful radiation levels will not exist in regions normally occupied by the public.
The earth station’s transmitter will be turned off during antenna maintenance so that the FCC MPE limit of 5 mW/cm2 will be
complied with for those regions with close proximity to the reflector that exceed acceptable levels.



Document Created: 2007-02-12 10:43:36
Document Modified: 2007-02-12 10:43:36

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