Attachment ComplianceDemo

This document pretains to SES-STA-20051107-01528 for Special Temporal Authority on a Satellite Earth Station filing.

IBFS_SESSTA2005110701528_462970

              Demonstration of Compliance with Section 25.222 Criteria

In response to Section 25.222(a) and (b) of the FCC’s Rules, C5 Communications, LLC.
(“C5”) provides the following information with respect to the Ku-band ESV remote
antenna specified in this application (Sea Tel Model No. 4003-7):

1.     25.222(a)(1) — (3). Off-Axis EIRP Spectral Density

        The Ku-band ESV remote antenna specified in this application meets the off-axis
ETRP spectral density requirements for co-polarized signals emitted from the ESV in the
plane of the geostationary satellite orbit as it appears at a particular earth station location
as required in Sections 25.222(a)(1) — (3). Figures 1 - 3 attached hereto contain
measured test data that demonstrates that the off-axis spectral density requirements are
satisfied for all relevant angles provided that the transmit power density at the antenna
input does not exceed -14 dBW/4 kHz of occupied bandwidth as required.

2.     25.222(a)(4) - Off-Axis Spurious Emissions

       The proposed ESV remote antenna meets the cross-polarized power spectral
density limits defined in Section 25.222(a)(4). Figures 1-3 attached hereto demonstrates
this compliance.

3.     25.222(a)(5) - Non-Circular ESV Antennas

       The ESV remote specified in this application uses circular antennas or, if slightly
asymmetric, the antenna performance power spectral density requirements are met in the
minor axis (see also Figure 1-3).

4.     25.222(a)(6) & (7) - Pointing Error and Auto-Shut Off

       C5 uses stabilized antenna systems for ESVs that operate with ±0.2° pointing
accuracy of the exact position of the satellite through which the ESV is communicating.
There are only a few exceptional conditions, described below, under which the antenna
could be mispointed by more than 0.5°. Even under these highly unusual conditions, the
ESV antenna controller can detect within 100 milliseconds if the pointing error should
ever exceed 0.5°and cease transmissions in 70 milliseconds. The controller would then
suppress transmissions until the pointing accuracy is within±0.2°.

       The stabilized antenna systems used by C5 employ closed-loop servo systems and
highly accurate sensors to continuously monitor the antenna’s position in inertial space.
When operating properly, the servo mechanism will keep the antenna pointing within
±0.1° RMS, 0.2° peak. See Figures 4-6 attached hereto.

    There always exists the possibility that unforeseen conditions can cause the antenna
to be mispointed outside of these specifications. Examples of some of these possible
conditions are:


       Unexpected mechanical disturbance from an external source;
       Operation in an unbalanced mechanical configuration;
       Operation subjected to tangential accelerations beyond the pedestal
       specifications (e.g., extremely heavy sea conditions);
       Failure of one or more sensors; or
       Failure of one or more drive motors.

    Even under any of the failure conditions cited above, the antenna controller can detect
a pointing error that exceeds 0.5° within 100 ms and cease transmissions immediately. As
noted above, the controller will not allow transmissions to resume until the pointing error
has diminished to within ± 0.2°.

    The sensors mounted on the antenna measure antenna position with a resolution of
better than 0.01°. The key to robust systems operation and reliable error reporting is that
the antenna position data is processed before being used to drive an error comparator. In
addition to antenna position, many sources of data are available to the system to make a
robust decision about the accuracy of the antenna pointing. They are:

       Satellite modem synch lock;
       Short-term integrated rate sensor antenna position;
       Long-term accelerometer and heading reference sensors readings;
       AGC level data; and
       Calculated azimuth and elevation positions based on ship latitude,
       longitude and desired satellite longitude.

    If for any reason the satellite modem should lose synch with the satellite down-link,
the system will cease transmission immediately, regardless of the pointing accuracy, and
not re-transmit until it has re-synchronized with the satellite and the pointing accuracy is
within ±0.2°.

    At all times the antenna controller compares a running average of the measured
azimuth and elevation to the desired azimuth and elevation positions. If the results exceed
the 0.5° threshold, then transmissions will cease immediately and not resume until the
pointing accuracy is within±0.20.

    The threshold detection algorithm has been used successfully for more than 10 years
to insure that the stabilized antenna system is operating within the desired limits.

    In addition, new software has recently been developed to continuously monitor the
instantaneous pedestal pointing error and will trip an error flag whenever an unexpected
event occurs that causes the pointing error to exceed 0.5 degrees. This flag will not clear
until the pedestal error remains below 0.2 degrees for a period of S seconds. The state of
this flag is used as an additional logic input to the existing “Transmit Mute” function of
the Sea Tel below decks controller. By connecting the “Transmit Mute Output” of the


Sea Tel below decks controller to the “Mute Input” of the satellite modem, the provisions
of Section 25.222(a)(7) are satisfied.

5.      25.222(a)(8) - Point of Contact.

        C5 maintains a Network Operations Center (“NOC”) at 1305 Industrial Park
Road, Shenandoah in Mount Jackson, Virginia on a 24-hours-a-day, 365-days-a-year
basis. All systems of C5’s clients are monitored and their emissions are controlled from
the NOC. Any client will be able to obtain information about its system and problem
resolution by calling the personnel on-duty in the NOC at +1(832) 495-4853. An
appropriate regulatory authority can also call the NOC to inquire about potential
interference. If it is determined that the interference is coming from a system under C5’s
control, the on-duty personnel can cease emissions from that unit immediately.

       There are standard escalation procedures in place for all types of incidents that the
on-duty personnel use to notify and involve the appropriate C5 staff members to resolve a
problem. In the most extreme cases, C5’s Chief Operations Officer will be called in to
take charge of the situation and resolve the problem.

6.     25.222(a)(9) - Excessive Radiation

      C5’s ESVs do not exceed the radiation guidelines of Section 1.1310 of the
FCC’s Rules, as demonstrated by the RF Compliance Assessment attached hereto.

7.     25.222(a)(10) - Geographic Area

        C5’s ESVs will operate in the Gulf of Mexico within the parameters of the
frequency coordinations. These ESVs operate in and out of Coastal U.S waters, in and
out of US Ports in Mississippi (Pascagoula), Louisiana(New Orleans) and Texas
(Houston, Freeport, Corpus Christi, Port Arthur). Some transit direct routes to Venezuela
and Mexico from and to the previous ports. At no time will these ESVs venture in areas
closer than 150km of Puerto Rico nor St. Croix, Virgin Islands.

8.     25.222(b)(1)(i-iv) – Density Charts and Tables

       C5 Attaches Figures 1-6 to meet these requirements.


9.     25.222(c)(1-3) – Operating Requirements

       C5’s ESV’s will operate under these guidelines and rules.

10.    25.222(d-e) - Proximities, NASA TDRSS and Radio Observatory

        At no time will C5’s ESVs be or pass in areas closer than 150km of Puerto Rico
nor St. Croix, Virgin Islands.


                     Certification of Peter G. Blaney, Sea Tel, Inc
.
I, Peter G. Blaney, Vice President for Engineering for Sea Tel, Inc(“Sea Tel”), hereby
certify:

1.     that the statements contained in the foregoing paragraphs 1-4 above are
       true and correct, and that Sea Tel maintains all relevant test data, available
       upon request, to verify these statements; and

2.     that the ESV antenna proposed herein (Sea Tel Model 4003-7) conforms
       to the gain pattern criteria of Section 25.209(a) and (b) of the FCC’s Rules, and,
       that combined with the input power density entered in Schedule B of the instant
       application, demonstrates that the off-axis ETRP spectral density envelope set
       forth in Sections 25.22l(a)(l) through (a)(4) will be met.



Executed on 9/30/05                   By: ______________/s/___________________
                                             Peter G. Blaney
                                             Vice President, Engineering
                                             Sea Tel, Inc


                       EMISSIONS DESIGNATOR



QPSK, 1/2 FEC, 384 KBPS, CONCATENATED CODE
14000.0000 - 14500.0000 MHz 842KG7W


                                                                     Figure 5



                                                               4003 Stability Accuracy Test
                                                            Az=45°, El=45°, R 25°@6s, P 15°@6s
     0.50

     0.40
Pointing Error (°)




     0.30

     0.20

     0.10

     0.00
                       0                     20             40                     60                   80             100                 120
                                                                                Time (s)


                                                               4003 Stability Accuracy Test
                                                            Az=45°, El=45°, R 25°@6s, P 15°@6s
                     0.50

                     0.40
Pointing Error (°)




                     0.30

                     0.20

                     0.10

                     0.00
                            0           10        20   30               40          50           60          70   80               90       100
                                                                        Pointing Error Distribution %


Ave Err (°)                     0.097                            RMS Err (°)      0.101                                      Max Err (°)    0.184


                                                                               Figure 4


                                                                                          4003 1.0M
                                                                                   14.25 GHz GAIN H-Plane

                                                                                                  45
                                                                                                  40
                                                                                                  35
                                                                                                  30
                                                                                                                                                29 - 25 log (a) dB
                                                                                                  25
   GAIN dBi




                                                                                                  20
                                                                                                  15
                                                                                                  10
                                                                                                       5
                                                                                                       0
              -10    -9     -8     -7     -6      -5         -4         -3         -2       -1     -5 0     1    2    3         4        5        6         7         8         9     10
                                                                                                  -10
                                                                                        Degrees (Narrow Sweep)


                                                                                          4003 1.0M
                                                                                   14.25 GHz GAIN H-Plane
                                                                                                 45
                                                                                                 40
                                                                                                 35
                                                                                                 30
                                                                                                 25
                                                                                                                          29 - 25 log (a) dB
                                                                                                 20
GAIN dBi




                                                                                                 15
                                                                                                                            8 dB
                                                                                                 10
                                                                                                  5
                                                                                                                                         32 - 25 log (a) dB
                                                                                                  0
              -180   -160   -140   -120    -100        -80        -60        -40         -20      -5 0     20    40   60           80     100         120       140       160       180
                                                                                                 -10
                                                                                                 -15
                                                                                                 -20
                                                                                        Degrees (Wide Sweep)


                                                                               Figure 3


                                                                                   4003, 14.25 GHz EIRP SD H-Plane

                                                                                                    30
                                                                                                    25
                                                                                                    20
                                                                                                    15
 EIRPsd dBW/4kHz




                                                                                                    10
                                                                                                     5
                                                                                                     0
                   -10    -9     -8     -7      -6      -5         -4         -3       -2      -1    -5 0    1       2    3    4    5     6         7         8         9     10

                                                                                                    -10
                                                                                                    -15
                                                                                                    -20
                                                                                                    -25
                                                                                            Degrees (Narrow Sweep)


                                                                                   4003, 14.25 GHz EIRP SD H-Plane

                                                                                                  30
                                                                                                  25
                                                                                                  20
                                                                                                  15
                                                                                                  10
EIRPsd dBW/4kHz




                                                                                                   5
                                                                                                   0
                   -180   -160   -140    -120    -100        -80        -60         -40      -20 -5 0       20       40   60   80   100       120       140       160       180
                                                                                                 -10
                                                                                                 -15
                                                                                                 -20
                                                                                                 -25
                                                                                                 -30
                                                                                                 -35
                                                                                                 -40
                                                                                                 -45
                                                                                            Degrees (Wide Sweep)


                                                                                   Figure 3


                                                                                    4003, 14.25 GHz EIRP SD E-Plane

                                                                                                      30
                                                                                                      25
                                                                                                      20
                                                                                                      15
EIRPsd dBW/4kHz




                                                                                                      10
                                                                                                       5
                                                                                                       0
                   -10    -9     -8      -7      -6          -5         -4     -3       -2       -1    -5 0   1       2    3    4        5         6         7         8     9    10

                                                                                                      -10
                                                                                                      -15
                                                                                                      -20
                                                                                                      -25
                                                                                             Degrees (Narrow Sweep)


                                                                                    4003, 14.25 GHz EIRP SD E-Plane

                                                                                                     30
                                                                                                     25
                                                                                                     20
                                                                                                     15
                                                                                                     10
 EIRPsd dBW/4kHz




                                                                                                      5
                                                                                                      0
                   -180   -160    -140    -120        -100        -80        -60      -40       -20 -5 0      20      40   60       80       100       120       140       160   180
                                                                                                    -10
                                                                                                    -15
                                                                                                    -20
                                                                                                    -25
                                                                                                    -30
                                                                                                    -35
                                                                                                    -40
                                                                                                    -45
                                                                                                    -50
                                                                                              Degrees (Wide Sweep)


                                                            Figure 1




                                                       4003, 14.25 GHz EIRPsd Cross Pol

                                                                             10
                                                                              5
                                                                              0
                   -10   -9   -8   -7   -6   -5   -4   -3      -2       -1    -5 0   1       2   3   4   5   6   7   8   9   10
EIRPsd Cross Pol




                                                                             -10
   dBW/4kHz




                                                                             -15
                                                                             -20
                                                                             -25
                                                                             -30
                                                                             -35
                                                                             -40
                                                                             -45
                                                                    Degrees (Narrow Sweep)


                                                                               Figure 6



                                         4003 Stability Accuracy Test                                                                          4003 Stability Accuracy Test

                      0.50                                                                                         0.50
                      0.40                                                                                         0.40
                      0.30                                                                                         0.30
                      0.20                                                                                         0.20
El Error (°)




                                                                                             Az Error (°)
                      0.10                                                                                         0.10
                      0.00                                                                                         0.00
                     -0.10                                                                                        -0.10
                     -0.20                                                                                        -0.20
                     -0.30                                                                                        -0.30
                     -0.40
                                                                                                                  -0.40
                     -0.50
                                                                                                                  -0.50
                                0   20       40          60         80   100          120
                                                                                                                             0        20             40               60           80                100        120
                                                      Time (s)                                                                                                     Time (s)


                                         4003 Stability Accuracy Test

                      0.50
                      0.40
                      0.30
                      0.20
Cl Error (°)




                      0.10
                      0.00
                     -0.10
                     -0.20
                     -0.30
                     -0.40
                     -0.50
                                0   20       40          60         80   100          120
                                                      Time (s)


                                         4003 Stability Accuracy Test                                                                         4003 Stability Accuracy Test
                                                                                                                                           Az=45°, El=45°, R 25°@6s, P 15°@6s
                     0.50                                                                                         0.50

                     0.40                                                                                         0.40
                                                                                             Pointing Error (°)
Pointing Error (°)




                     0.30                                                                                         0.30

                     0.20                                                                                         0.20

                                                                                                                  0.10
                     0.10

                                                                                                                  0.00
                     0.00
                                                                                                                         0       10       20    30        40         50       60        70      80         90   100
                            0       20      40           60         80   100          120
                                                      Time (s)                                                                                                       %
                                                                                            Ave Err (°)                           0.097              RMS Err (°)          0.101              Max Err (°)        0.184




                                                                                            SeaTel                                                                                                                      4/8/04


                                                          Analysis • Production • Implementation




                             FCC RF COMPLIANCE ASSESSMENT

                                                Prepared for

                                       C5 COMMUNICATIONS

                                  1.0-METER VSAT OPERATION



       The following is an assessment of compliance with applicable FCC limits for
maximum permissible exposure (MPE) for very small aperture terminals (VSATs)
operated by C5 Communications (C5).

        As will be explained, the results of the assessment apply to Ku-band VSAT
operations whose antenna diameters are no smaller than 1.0 meters and whose antenna
input power is up to 8 watts. In all cases, immediate access to the antennas
is limited to C5’s personnel who apply standard RF safety procedures. The MPE limit
that applies is the one for “controlled” (occupational) exposure.

        Based on the results of the mathematical analysis of potential RF exposure levels,
the limited access to the areas of interest, and the application of standard RF safety
procedures, it is our expert conclusion that C5’s VSAT operations are in compliance with
the FCC regulations and applicable MPE limits.
.
        The sections that follow provide all the necessary background underlying the
analysis and our conclusion regarding compliance.

Operational Data

The relevant data for the subject operation is summarized as follows:

       Transmitting Frequency Bands:                         14.0 — 14.5 GHz
       Antenna Type:                                         Aperture
       Antenna Dimension (Diameter):                         1.03 meters
       Max Power Input to Antenna (at flange):               8 watts




          6300 W. Loop South, Suite 175 • Bellaire • Texas • 713.668.8085 , 713-893-6075 [fax]


                                                           Analysis • Production • Implementation




Applicable MPE Limit

       For frequencies above 1.5 GHz, the applicable FCC MPE limit for acceptable,
continuous exposure of the general population is 1.0 milliwatt per square centimeter
(mW/cm2), and for “controlled” occupational exposure, the limit is 5.0 mW/cm2.

         Immediate access to C5’s VSATs is restricted to trained C5 personnel, and thus
the latter limit applies.

FCC Models and Calculations

        FCC Bulletin OET 65 provides standardized formulas for calculating the power
density in both of the areas of possible interest here: (1) directly in front of the antenna, at
the face and farther away but still in the main beam; and (2) to the side of the antenna.
Each area of interest will be addressed in the subsections below.

       Note that in each of the models, the parameters of interest focus on determining
the power density at various locations around the antenna. Specifically, the antenna
parameters of interest are the power input and the antenna diameter.

       In this case, all C5 VSAT operations of interest use an antenna diameter of 1.03
meters, and the maximum antenna input power in either frequency band is 8 watts.
Additionally, all C5 VSAT installations are atop a pedestal, 6ft in height above
surrounding decks, placing the antenna radiation center at over 8ft above surrounding
decks. Therefore, a single compliance assessment can be applied to all of C5’s VSAT
operations satisfying these criteria.

Potential Exposure Levels Directly in Front of the Antenna

         Before proceeding to these calculations, it is relevant to note that potential
exposure in the areas in front of the antenna — whether at the surface of the antenna or in
the extended main beam — is obviated by standard practices involving RF safety and RF
design. As mentioned earlier, immediate access to the antennas is limited to C5’s
trained personnel; if work needs to be performed on the antennas, it is standard RF
safety practice to remove the input power. That basically prevents any exposure issue
right at the face of the antenna. Potential exposure in the extended beam of the antenna
is obviated by sound engineering practice; the beam of each VSAT requires a clear,
unobstructed view of the satellite(s) with which it communicates. Proper engineering
and positioning of the antenna prevents the beam from being obstructed by any nearby
object, including human beings. Thus, the “potential” exposure in these areas is never
“actual”. However, the results of these calculations do serve as confirmation of the need
for standard safety procedures, and also serve as a reference point for calculations of RF
levels to the side of the antennas.




           6300 W. Loop South, Suite 175 • Bellaire • Texas • 713.668.8085 , 713-893-6075 [fax]


                                                          Analysis • Production • Implementation

       According to Bulletin CET 65, the applicable formula for power density (S) at the
antennae surface is as follows:

                                               S = 4P
                                                   A

where P represents the antenna input power and A is the surface area of the antenna.

In this case, with 8 watts maximum input power and an antenna diameter of 1.03
meters, the power density at the antenna surface is 3.84 mW/cm2, which does NOT
exceed the FCC occupational MPE limit of 5 for this frequency. Though RF safety
procedures should always be observed when work needs to be performed in this area,
there exists no FCC requirement in this situation.

The formula for near-field, on-axis power density in front of the antenna is as follows:

                                    S = 16 * e * P / ( pi * D2)

where “e” represents the antenna illumination efficiency and D is the antenna diameter.
In this case, when we apply an illumination efficiency of 0.65, the result of the
calculation is 2.496 mW/cm2, which also does NOT exceed the occupational MPE limit
of 5 for these frequencies. As described earlier, though, the need for an unobstructed
view to the satellites and sound engineering design obviates concern over actual exposure
in this area. The calculated result here, however, is used in the analysis of potential
exposure to the immediate side of the antenna, which is addressed in the subsection that
follows.

Potential Exposure Levels to the Side of the Antenna.

       It is well founded that the near-field power density drops off dramatically outside
the imaginary cylinder extending from the surface along the axis of the main beam of an
aperture antenna.

       According to Bulletin OET 65, if the point of interest is at least one antenna
diameter removed from the center of the main beam, the power density at that point
would be at least a factor of 100 lower than the value calculated for the equivalent
distance in the main beam.

        The previous calculation (for immediately in front of the antenna) demonstrated
that the power density there is 3.84 mW/cm2, which is equivalent to 76.8 percent of the
limit. At a distance of one antenna diameter (1.03 meters) to the side of the antenna, the
FCC model says that the RF level would be no more than 0.02496 mW/cm2, equivalent
to about .49 percent of the occupational limit and 2.4 percent of the General Population
limits.

Compliance Conclusion



          6300 W. Loop South, Suite 175 • Bellaire • Texas • 713.668.8085 , 713-893-6075 [fax]


                                                          Analysis • Production • Implementation



Based on the results of the calculations alone, and when considered along with access
restrictions and standard safety procedures, it is our conclusion that the operation of C5’s
Ku-band 1.03 meter VSATs satisfy the compliance requirements in the FCC regulations.




Mark Slater
Chief Technology Officer
Rix, USA
6300 W. Loop South – Suite 175
Bellaire, Texas 77401
Tel: 713-668-8085




          6300 W. Loop South, Suite 175 • Bellaire • Texas • 713.668.8085 , 713-893-6075 [fax]



Document Created: 2005-11-08 07:32:22
Document Modified: 2005-11-08 07:32:22

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