Attachment Attachment A

This document pretains to SES-LIC-20121009-00903 for License on a Satellite Earth Station filing.

IBFS_SESLIC2012100900903_970611

                                      IP Access International, Inc.

                                       FCC Form 312 – Exhibit A



The following exhibit contains the following documents:

       Radiation Hazard Study – 96cm Offset Feed Earth Station ku-band Antenna with 6W BUC

       Radiation Hazard Study – 1.2m Offset Feed Earth Station ku-band Antenna with 6W BUC

       Radiation Hazard Study – 1.8m Offset Feed Earth Station ku-band Antenna with 6W BUC



A Radiation Hazard Study has not been included for the 9.3m Ku-band antenna installed at the Intelsat
Napa, CA teleport (Site ID: NAPA, Antenna ID: HUB) – this antenna was installed by, and is the full
responsibility of, Intelsat Corporation. This antenna has been assigned the FCC call sign: E000274.


                 Radiation Hazard Study

96 cm Offset Feed Earth Station ku-band Antenna with 6W BUC

This analysis predicts the radiation levels around a earth station comprised of one aperture (reflector)
type antenna. This report is developed in accordance with the prediction methods contained in OET
Bulletin No. 65, Evaluating Compliance with FCC Guidelines for Human Exposure to Radio Frequency
Electromagnetic Fields, Edition 97-01, Section 2 Prediction Methods, Aperture Antennas, pp 26-30.

The maximum level of non-ionizing radiation to which employees may be exposed is limited to a power
density level of 5 milliwatts per square centimeter (5 mW/cm²) averaged over any 6 minute period in a
controlled environment and the maximum level of non-ionizing radiation to which the general public is
exposed is limited to a power density level of 1 milliwatt per square centimeter (1 mW/cm²) averaged
over any 30 minute period in a uncontrolled environment.

Note that the worse-case radiation hazards exist along the beam axis. Under normal circumstances, it is
highly unlikely that the antenna axis will be aligned with any occupied area since that would represent a
blockage to the desired signals, thus rendering the link unuseable.



Earth Station Technical Parameters

Antenna diameter                  96 cm
Antenna Isotropic gain            41.2 dBi
Maximum Transmit Power            6 Watts
Number of carriers                1
Nominal Frequency                 14250 MHz


In the following sections, the power density in the above regions, as well as other critically important
areas will be calculated and evaluated.




X2nsat, Inc.                        Radiation Hazard Study – 96 cm ku        7 December 2011      Page 1 of 4


On-axis Near-Field Region

The geometrical limits of the radiated power in the near field approximate a cylindrical volume with a
diameter equal to that of the antenna. In the near field, the power density is neither uniform nor does its
value vary uniformly with distance from the antenna. For the purpose of considering radiation hazard it is
assumed that the on-axis flux density is at its maximum value throughout the length of this region. The
length of this region, i.e., the distance from the antenna to the end of the near field, is given by the
equation (1).

(1) Lnf = D²/(4λ)

Where Lnf = length to end of the near field,

Where D = antenna diameter = 96 cm

Where λ = wavelength at 14.250 GHz = 21.0 x10-3 meters.

From equation (1) it is found that the distance to the end of the near field is 11 meters.


The maximum power flux density in the near field PDnf is given by:

(2) PDnf = 16 Pt ŋ/(πD²)

Where Pt is the maximum power transmitted by the amplifier (6 Watts).

Where ŋ = Antenna Efficiency

Antenna efficiency can be estimated, or a reasonable approximation for circular apertures can be
obtained from the ratio of the effective aperture area to the physical area as follows:

          ŋ = (Gλ²/4π)/(πD²/4) = Gλ²/(π²D²) = 0.64

Where G = the on-axis gain of the antenna (41.2 dBi at 14.250 GHz)

From equation (2), we see that

                           PDnf = 2.13 mW/cm²

Evaluation

          Uncontrolled Environment          Does Not Complies with FCC Limit
                                            This area will not be accessible to the general public

          Controlled Environment            Complies with FCC Limit of 5 milliwatts per square centimeter




X2nsat, Inc.                         Radiation Hazard Study – 96 cm ku       7 December 2011         Page 2 of 4


On-axis Transition Region

The transition region is located between the near and far field regions. As stated in Bulletin 65, the power
density begins to vary inversely with distance in the transition region. The maximum power density in the
transition region will not exceed that calculated for the near field region, and the transition region begins
at that value.

The power density in the near field region, as shown above, will not exceed 2.13 mW/cm².

Evaluation
        Uncontrolled Environment           Does Not Complies with FCC Limit
                                           This area will not be accessible to the general public

          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter


On-axis Far-Field Region
Free-space power density is maximum on-axis, varies inversely with the square of the of the distance
and may be calculated from equation (3).

(3) PDff = GPt/(4π R²)

Where PDff = the power flux density on-axis in the far field,

R = the distance to the far field region and is found from equation (4).

(4) R = 0.6D²/λ

From equation (4) it is found that the distance to the far field is 26 meters.

And, PDff is found from equation (3) as follows: PDff = 0.91 mW/cm²

Evaluation
        Uncontrolled Environment           Complies with FCC Limit of 1 milliwatt per square centimeter
        Controlled Environment             Complies with FCC Limit of 5 milliwatts per square centimeter


Region Between Feed Flange and Reflector

Transmissions from the feed horn are directed toward the reflector surface, and are confined within a
conical shape defined by the feed. The energy between the feed and reflector surface can be calculated
by determining the power density at the feed flange. This can be accomplished as follows:

Power Density at Feed Flange, PDfeed = 4*Pt/Fa

Where Fa = Area of Feed Window = π*Df²/4

Where Df = 7 cm           for      Fa = 38.5 cm²

                                   PDfeed = 624 mW/cm²

The energy between the feed horn and reflector is conceded to be in excess of any limits for maximum
permissible exposure. This area will not be accessible to the general public. Operators and technicians
have received training specifying this area as a high exposure area. Procedures are established that
assure that the transmitter is turned off before access by maintenance personnel to this area.


X2nsat, Inc.                        Radiation Hazard Study – 96 cm ku            7 December 2011    Page 3 of 4


Main Reflector Region
The power density in the main reflector region is determined in the same manner as the power density at
the feed flange, above, but the area is now the area of the reflector aperture:

Power Density at Reflector Surface, PDreflector = 4*Pt/Sa

Where Sa = Surface Area of Reflector = 0.72 m²

                                  PDreflector = 3.32 mW/cm²

The power densities at or around the reflector surface are above the limit for maximum permissible
exposure in a Uncontrolled Environment of 1 mW/cm² , and below the maximum permissible exposure in
a Controlled Environment of 5 mW/cm² . This area will not be accessible to the general public.

Off-axis Levels at the Far Field Limit and Beyond

In the far field region, the power is distributed in a pattern of maxima and minima (sidelobes) as a
function of the off-axis angle between the antenna on-axis center line and the point of interest. The on-
axis main-beam will be the location of the greatest of these maxima. The on-axis power density
calculated above represent the maximum exposure levels that the system can produce. Off-axis power
densities will be considerably less and hence comply with FCC limits.

Off-axis Levels at the Near Field and in the Transition Region
According to Bulletin 65, off-axis calculations in the near field may be performed as follows: assuming
that the point of interest is at least one antenna diameter removed from the center of the main beam, the
power density at that point is at least a factor of 100 (20dB) less than the value calculated for the
equivalent on-axis power density in the main beam. Therefore, for regions at least D meters away from
the center line of the dish, whether behind, below, or in front under of the antenna's main beam, the
power density exposure is at least 20 dB below the main beam level as follows:

          PDnf(off-axis) = PDnf /100 = 0.021 mW/cm²          Referred to as “Dish Diameter Rule”

Evaluation
        Uncontrolled Environment           Complies with FCC Limit of 1 milliwatt per square centimeter
        Controlled Environment             Complies with FCC Limit of 5 milliwatts per square centimeter

Evaluation of Safe Occupancy Area in Front of Antenna
As covered in the section above “Off-axis levels at the Near Field and in the Transition Region”, the off-
axis levels are well below the FCC limit for controlled environment. Therefore, no fencing or barrier is
required to prevent access to the area in front of the antenna by employees. This area will not be
accessible to the general public.

The area not to be accessed by maintenance personnel without the transmitter being turned off is the
area between the feed horn and the reflector.

Conclusion
Based on the above analysis it is concluded that harmful levels of radiation will not exist in regions
accessible to the general public, or to the earth station’s operating personnel.


Study Prepared by:        Phil Kratchanov
                         x2nsat RF Engineer phil@x2nsat.com


X2nsat, Inc.                        Radiation Hazard Study – 96 cm ku       7 December 2011        Page 4 of 4


                 Radiation Hazard Study

1.2m Offset Feed Earth Station ku-band Antenna with 6W BUC

This analysis predicts the radiation levels around a earth station comprised of one aperture (reflector)
type antenna. This report is developed in accordance with the prediction methods contained in OET
Bulletin No. 65, Evaluating Compliance with FCC Guidelines for Human Exposure to Radio Frequency
Electromagnetic Fields, Edition 97-01, Section 2 Prediction Methods, Aperture Antennas, pp 26-30.

The maximum level of non-ionizing radiation to which employees may be exposed is limited to a power
density level of 5 milliwatts per square centimeter (5 mW/cm²) averaged over any 6 minute period in a
controlled environment and the maximum level of non-ionizing radiation to which the general public is
exposed is limited to a power density level of 1 milliwatt per square centimeter (1 mW/cm²) averaged
over any 30 minute period in a uncontrolled environment.

Note that the worse-case radiation hazards exist along the beam axis. Under normal circumstances, it is
highly unlikely that the antenna axis will be aligned with any occupied area since that would represent a
blockage to the desired signals, thus rendering the link unuseable.



Earth Station Technical Parameters

Antenna diameter                  1.2 m
Antenna Isotropic gain            43.2 dBi
Maximum Transmit Power            6 Watts
Number of carriers                1
Nominal Frequency                 14250 MHz


In the following sections, the power density in the above regions, as well as other critically important
areas will be calculated and evaluated.




X2nsat, Inc.                        Radiation Hazard Study – 1.2m ku         6 December 2011      Page 1 of 4


On-axis Near-Field Region

The geometrical limits of the radiated power in the near field approximate a cylindrical volume with a
diameter equal to that of the antenna. In the near field, the power density is neither uniform nor does its
value vary uniformly with distance from the antenna. For the purpose of considering radiation hazard it is
assumed that the on-axis flux density is at its maximum value throughout the length of this region. The
length of this region, i.e., the distance from the antenna to the end of the near field, is given by the
equation (1).

(1) Lnf = D²/(4λ)

Where Lnf = length to end of the near field,

Where D = antenna diameter = 1.2 m

Where λ = wavelength at 14.250 GHz = 21.0 x10-3 meters.

From equation (1) it is found that the distance to the end of the near field is 17 meters.


The maximum power flux density in the near field PDnf is given by:

(2) PDnf = 16 Pt ŋ/(πD²)

Where Pt is the maximum power transmitted by the amplifier (4 Watts).

Where ŋ = Antenna Efficiency

Antenna efficiency can be estimated, or a reasonable approximation for circular apertures can be
obtained from the ratio of the effective aperture area to the physical area as follows:

          ŋ = (Gλ²/4π)/(πD²/4) = Gλ²/(π²D²) = 0.65

Where G = the on-axis gain of the antenna (43.2 dBi at 14.250 GHz)

From equation (2), we see that

                           PDnf = 1.38 mW/cm²

Evaluation

          Uncontrolled Environment         Does Not Complies with FCC Limit
                                           This area will not be accessible to the general public

          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter




X2nsat, Inc.                         Radiation Hazard Study – 1.2m ku        6 December 2011        Page 2 of 4


On-axis Transition Region

The transition region is located between the near and far field regions. As stated in Bulletin 65, the power
density begins to vary inversely with distance in the transition region. The maximum power density in the
transition region will not exceed that calculated for the near field region, and the transition region begins
at that value.

The power density in the near field region, as shown above, will not exceed 1.38 mW/cm².

Evaluation
        Uncontrolled Environment           Does Not Complies with FCC Limit
                                           This area will not be accessible to the general public

          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter


On-axis Far-Field Region
Free-space power density is maximum on-axis, varies inversely with the square of the of the distance
and may be calculated from equation (3).

(3) PDff = GPt/(4π R²)

Where PDff = the power flux density on-axis in the far field,

R = the distance to the far field region and is found from equation (4).

(4) R = 0.6D²/λ

From equation (4) it is found that the distance to the far field is 41 meters.

And, PDff is found from equation (3) as follows: PDff = 0.59 mW/cm²

Evaluation
        Uncontrolled Environment           Complies with FCC Limit of 1 milliwatt per square centimeter
        Controlled Environment             Complies with FCC Limit of 5 milliwatts per square centimeter


Region Between Feed Flange and Reflector

Transmissions from the feed horn are directed toward the reflector surface, and are confined within a
conical shape defined by the feed. The energy between the feed and reflector surface can be calculated
by determining the power density at the feed flange. This can be accomplished as follows:

Power Density at Feed Flange, PDfeed = 4*Pt/Fa

Where Fa = Area of Feed Window = π*Df²/4

Where Df = 7 cm           for      Fa = 38.5 cm²

                                   PDfeed = 624 mW/cm²

The energy between the feed horn and reflector is conceded to be in excess of any limits for maximum
permissible exposure. This area will not be accessible to the general public. Operators and technicians
have received training specifying this area as a high exposure area. Procedures are established that
assure that the transmitter is turned off before access by maintenance personnel to this area.


X2nsat, Inc.                         Radiation Hazard Study – 1.2m ku            6 December 2011    Page 3 of 4


Main Reflector Region
The power density in the main reflector region is determined in the same manner as the power density at
the feed flange, above, but the area is now the area of the reflector aperture:

Power Density at Reflector Surface, PDreflector = 4*Pt/Sa

Where Sa = Surface Area of Reflector = 1.13 m²

                                  PDreflector = 2.12 mW/cm²

The power densities at or around the reflector surface are above the limit for maximum permissible
exposure in a Uncontrolled Environment of 1 mW/cm² , and below the maximum permissible exposure in
a Controlled Environment of 5 mW/cm² . This area will not be accessible to the general public.

Off-axis Levels at the Far Field Limit and Beyond

In the far field region, the power is distributed in a pattern of maxima and minima (sidelobes) as a
function of the off-axis angle between the antenna on-axis center line and the point of interest. The on-
axis main-beam will be the location of the greatest of these maxima. The on-axis power density
calculated above represent the maximum exposure levels that the system can produce. Off-axis power
densities will be considerably less and hence comply with FCC limits.

Off-axis Levels at the Near Field and in the Transition Region
According to Bulletin 65, off-axis calculations in the near field may be performed as follows: assuming
that the point of interest is at least one antenna diameter removed from the center of the main beam, the
power density at that point is at least a factor of 100 (20dB) less than the value calculated for the
equivalent on-axis power density in the main beam. Therefore, for regions at least D meters away from
the center line of the dish, whether behind, below, or in front under of the antenna's main beam, the
power density exposure is at least 20 dB below the main beam level as follows:

          PDnf(off-axis) = PDnf /100 = 0.014 mW/cm²          Referred to as “Dish Diameter Rule”

Evaluation
        Uncontrolled Environment          Complies with FCC Limit of 1 milliwatt per square centimeter
        Controlled Environment            Complies with FCC Limit of 5 milliwatts per square centimeter

Evaluation of Safe Occupancy Area in Front of Antenna
As covered in the section above “Off-axis levels at the Near Field and in the Transition Region”, the off-
axis levels are well below the FCC limit for controlled environment. Therefore, no fencing or barrier is
required to prevent access to the area in front of the antenna by employees. This area will not be
accessible to the general public.

The area not to be accessed by maintenance personnel without the transmitter being turned off is the
area between the feed horn and the reflector.

Conclusion
Based on the above analysis it is concluded that harmful levels of radiation will not exist in regions
accessible to the general public, or to the earth station’s operating personnel.


Study Prepared by:        Phil Kratchanov
                         x2nsat RF Engineer phil@x2nsat.com


X2nsat, Inc.                        Radiation Hazard Study – 1.2m ku        6 December 2011        Page 4 of 4


                 Radiation Hazard Study

1.8m Offset Feed Earth Station ku-band Antenna with 6W BUC

This analysis predicts the radiation levels around a earth station comprised of one aperture (reflector)
type antenna. This report is developed in accordance with the prediction methods contained in OET
Bulletin No. 65, Evaluating Compliance with FCC Guidelines for Human Exposure to Radio Frequency
Electromagnetic Fields, Edition 97-01, Section 2 Prediction Methods, Aperture Antennas, pp 26-30.

The maximum level of non-ionizing radiation to which employees may be exposed is limited to a power
density level of 5 milliwatts per square centimeter (5 mW/cm²) averaged over any 6 minute period in a
controlled environment and the maximum level of non-ionizing radiation to which the general public is
exposed is limited to a power density level of 1 milliwatt per square centimeter (1 mW/cm²) averaged
over any 30 minute period in a uncontrolled environment.

Note that the worse-case radiation hazards exist along the beam axis. Under normal circumstances, it is
highly unlikely that the antenna axis will be aligned with any occupied area since that would represent a
blockage to the desired signals, thus rendering the link unuseable.



Earth Station Technical Parameters

Antenna diameter                  1.8m
Antenna Isotropic gain            46.5 dBi
Maximum Transmit Power            6 Watts
Number of carriers                1
Nominal Frequency                 14250 MHz


In the following sections, the power density in the above regions, as well as other critically important
areas will be calculated and evaluated.




X2nsat, Inc.                        Radiation Hazard Study – 1.8m ku         6 December 2011      Page 1 of 5


On-axis Near-Field Region

The geometrical limits of the radiated power in the near field approximate a cylindrical volume with a
diameter equal to that of the antenna. In the near field, the power density is neither uniform nor does its
value vary uniformly with distance from the antenna. For the purpose of considering radiation hazard it is
assumed that the on-axis flux density is at its maximum value throughout the length of this region. The
length of this region, i.e., the distance from the antenna to the end of the near field, is given by the
equation (1).

(1) Lnf = D²/(4λ)

Where Lnf = length to end of the near field,

Where D = antenna diameter

Where λ = wavelength at 14.250 GHz = 21.0 x10-3 meters.

From equation (1) it is found that the distance to the end of the near field is 38 meters.


The maximum power flux density in the near field PDnf is given by:

(2) PDnf = 16 Pt ŋ/(πD²)

Where Pt is the maximum power transmitted by the amplifier (6 Watts).

Where ŋ = Antenna Efficiency

Antenna efficiency can be estimated, or a reasonable approximation for circular apertures can be
obtained from the ratio of the effective aperture area to the physical area as follows:

          ŋ = (Gλ²/4π)/(πD²/4) = Gλ²/(π²D²) = 0.62

Where G = the on-axis gain of the antenna (46.5 dBi at 14.250 GHz)

From equation (2), we see that

                           PDnf = 0.58 mW/cm²

Evaluation

          Uncontrolled Environment         Complies with FCC Limit of 1 milliwatt per square centimeter
          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter




X2nsat, Inc.                         Radiation Hazard Study – 1.8m ku        6 December 2011    Page 2 of 5


On-axis Transition Region

The transition region is located between the near and far field regions. As stated in Bulletin 65, the power
density begins to vary inversely with distance in the transition region. The maximum power density in the
transition region will not exceed that calculated for the near field region, and the transition region begins
at that value.

The power density in the near field region, as shown above, will not exceed 0.58 mW/cm².

Evaluation

          Uncontrolled Environment         Complies with FCC Limit of 1 milliwatt per square centimeter
          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter




On-axis Far-Field Region
Free-space power density is maximum on-axis, varies inversely with the square of the of the distance
and may be calculated from equation (3).

(3) PDff = GPt/(4π R²)

Where PDff = the power flux density on-axis in the far field,

R = the distance to the far field region and is found from equation (4).

(4) R = 0.6D²/λ

From equation (4) it is found that the distance to the far field is 92 meters.

And, PDff is found from equation (3) as follows:

                                                     PDff = 0.25 mW/cm²

Evaluation

          Uncontrolled Environment         Complies with FCC Limit of 1 milliwatt per square centimeter
          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter




X2nsat, Inc.                         Radiation Hazard Study – 1.8m ku            6 December 2011   Page 3 of 5


Region Between Feed Flange and Reflector

Transmissions from the feed horn are directed toward the reflector surface, and are confined within a
conical shape defined by the feed. The energy between the feed and reflector surface can be calculated
by determining the power density at the feed flange. This can be accomplished as follows:

Power Density at Feed Flange, PDfeed = 4*Pt/Fa

Where Fa = Area of Feed Window = π*Df²/4

Where Df = 7 cm

Fa = 38.5 cm²

                                 PDfeed = 624 mW/cm²

The energy between the feed horn and reflector is conceded to be in excess of any limits for maximum
permissible exposure. This area will not be accessible to the general public. Operators and technicians
have received training specifying this area as a high exposure area. Procedures are established that
assure that the transmitter is turned off before access by maintenance personnel to this area.




Main Reflector Region
The power density in the main reflector region is determined in the same manner as the power density at
the feed flange, above, but the area is now the area of the reflector aperture:

Power Density at Reflector Surface, PDreflector = 4*Pt/Sa

Where Sa = Surface Area of Reflector = 2.54 m²

                                 PDreflector = 0.94 mW/cm²

The power densities at or around the reflector surface are just below the limits for maximum permissible
exposure. This area will not be accessible to the general public. Operators and technicians have received
training specifying this area as a high exposure area. Procedures are established that assure that the
transmitter is turned off before access by maintenance personnel to this area.




Off-axis Levels at the Far Field Limit and Beyond

In the far field region, the power is distributed in a pattern of maxima and minima (sidelobes) as a
function of the off-axis angle between the antenna on-axis center line and the point of interest. The on-
axis main-beam will be the location of the greatest of these maxima. The on-axis power density
calculated above represent the maximum exposure levels that the system can produce. Off-axis power
densities will be considerably less and hence comply with FCC limits.




X2nsat, Inc.                       Radiation Hazard Study – 1.8m ku       6 December 2011      Page 4 of 5


Off-axis Levels at the Near Field and in the Transition Region
According to Bulletin 65, off-axis calculations in the near field may be performed as follows: assuming
that the point of interest is at least one antenna diameter removed from the center of the main beam, the
power density at that point is at least a factor of 100 (20dB) less than the value calculated for the
equivalent on-axis power density in the main beam. Therefore, for regions at least D meters away from
the center line of the dish, whether behind, below, or in front under of the antenna's main beam, the
power density exposure is at least 20 dB below the main beam level as follows:

          PDnf(off-axis) = PDnf /100 = 0.006 mW/cm²

Evaluation

          Uncontrolled Environment         Complies with FCC Limit of 1 milliwatt per square centimeter
          Controlled Environment           Complies with FCC Limit of 5 milliwatts per square centimeter



Evaluation of Safe Occupancy Area in Front of Antenna
As covered in the section above “Off-axis levels at the Near Field and in the Transition Region”, the off-
axis levels are well below the FCC limits. Therefore, no fencing or barrier is required to prevent access
to the area in front of the antenna by employees. This area will not be accessible to the general public.

The area not to be accessed by maintenance personnel without the transmitter being turned off is the
area between the feed horn and the reflector.




Conclusion
Based on the above analysis it is concluded that harmful levels of radiation will not exist in regions
accessible to the general public or to the earth station’s operating personnel.




Study Prepared by:        Phil Kratchanov
                         x2nsat RF Engineer

                         phil@x2nsat.com




X2nsat, Inc.                         Radiation Hazard Study – 1.8m ku       6 December 2011       Page 5 of 5



Document Created: 2012-02-24 14:52:37
Document Modified: 2012-02-24 14:52:37

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