Product Description SUPPLEMENT by Ryan N. Terry SES-LIC-20151016-00712 ASC-9 4m Product Des

Attachment ASC-9 4m Product Des

ASC-9 4m Product Des

SUPPLEMENT submitted by Ryan N. Terry

Product Description

2015-12-21

This document pretains to SES-LIC-20151016-00712 for License on a Satellite Earth Station filing.

IBFS_SESLIC2015101600712_1119423

automatically be negated while in step track mode. However, the ASC Signal SRT also
incorporates a precision z-axis drive mechanism that adaptively re-focuses the antenna
system and maintains optimal performance through all weather and anti-ice events.

1.1.2 Antenna RF Description and Performance
The 9.4m optical design has been optimized for high efficiency Ka-band performance and
providing compliance to all applicable regulatory requirements. The 9.4 Meter Ka-Band
antenna is fully compliant (as a minimum) with the following referenced Regulatory Agency
specifications:

 Federal Communications Commission Rules and Regulations, Title 47, C.F.R. Part
25.209, as amended.
 ITU-R, S.580-5 and S.465-5 Recommendations for Pattern Performance for 2 degree
satellite spacing, as amended

Specifically, the proposed antenna complies with the radiation pattern envelope (RPE)
performance for 1 - 180 degrees angles as per ITU-R, S.580-5, S.465-5, and FCC part 25:

Transmit pattern curve
29-25 LOG  dBi (1º    20)
-3.5 dBi (20<   26.3)
32-25 LOG  dBi (26.3<   48)
-10 dBi ( > 48)

Transmit pattern sidelobe excursions

No excursions for 1º   7
3dB max excursions for  > 7
10% max integr. excursions for 7<   180

Examples of transmit and receive band antenna patterns are shown on the following pages:

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In addition to the above redundancy from the antenna mechanics, the NGC also will be
configured to offer redundancy in the electronics, as described in the following.

1.1.7 Antenna Control System Architecture

1.1.7.1 Indoor Antenna Control System Equipment

The ASC NGC indoor unit (NGC-IDU) is a standard ASC Signal product, offered to and used
with a variety of options by our customers.

For some proposals Monopulse Tracking implementation, the indoor equipment for the
antenna control system will consist of:

 Two (2) NGC-IDU units, configured as a 1:1 redundant pair with automatic reversion,
with separate optical fiber links to the NGC-ODU equipment. Each NGC-IDU would be
equipped with all necessary software licenses to support all tracking modes (steptrack,
predictive track, monopulse).

 Two (2) monopulse-capable tracking receivers, paired with NGC-IDU units. The
primary tracking receiver would be configured for monopulse. Which receiver is used
would depend on which NGC-IDU was active. The monopulse tracking receiver is
connected to a monopulse tracking plate in the hub.

A Cisco Catalyst 2960 switch will be supplied for interconnecting the antenna control system
equipment.

The indoor equipment will be linked to the outdoor equipment using optical fiber (for the
antenna control IDU-to-ODU units) and coaxial cable (for the tracking receiver to tracking
plate interface).

The M&C system will interface to the control system using the NGC-IDU’s SNMP agent. This
will include proxy control of the tracking receiver and other equipment attached to the
Antenna Control System.

In addition to tracking, the NGC-IDU will also provide the following basic functions:

 Position designate pointing, and jog functions for all five major axes.
 Display of look angles to a default resolution of 0.001°, with optional resolution to
0.0001°.

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(b) sensitivity to asymmetry in the reflector that distorts the shape of the “delta”
pattern versus the “sum” pattern. Large Ka-band antennas in particular,
because of the short wavelength, are subject to significant pattern
asymmetries due to solar heating. Under some clear-sky conditions, this effect
may make monopulse tracking performance less than desired. In these cases
the customer should fall back to step track.

Note that monopulse tracking cannot focus the Z axis of the SRT. This process must be
done through an occasional step track process.

ii. Step track¸ where through small depointings of the receive beam, and measurement of
the resulting signal loss, peak signal angles are empirically derived. This approach is
well-understood and universal.

The main drawback to step track for this application is that de-pointing the receive
beam enough to make for a measureable loss will cause a significant loss in the
transmit uplink. Smaller step sizes reduce the loss but they also decrease the RMS
accuracy due to the lack of resolution in the signal strength. Since the customer
requires a 0.3dB max drop (10% of beamwidth), a very small step size (5%) coupled
with very long integration times (10-15s) will be required to get reasonable
performance. This makes it suitable as a fallback or emergency tracking approach but
for normal operation it will have trouble meeting the desired performance.

iii. Orbital prediction or “SmarTrack”, where step track is used to construct a
mathematical model of the motion of the satellite which is constrained by
astrodynamics. Once the model is built, it is used to predict the motion of satellite, and
therefore the antenna.

The problem with orbital prediction is it was developed to solve a different problem
than the one presented by most large-aperture Ka-band systems. It assumes that the
orbital motion of the satellite is the only significant variable in the beam angle. For
well-station-kept satellites (i < 0.1°) the motion due to astrodynamics is comparable in
magnitude to a completely uncorrelated but non-random beam deformation due to
thermal distortion of the main reflector under solar load. Since the orbital models all
assume that pointing feedback noise is just noise, and since they assume that the
filtered pointing angles correspond to true look angles of satellites in Keplerian orbits,
the existence of non-random noise makes the orbital prediction process inaccurate.
ASC Signal’s experience is that no orbital-derivation algorithm is useful for low-
inclination Ka-band satellites with large apertures due to these factors.

iv. Ephemeris Predictive track (NORAD/Intelsat elements), where an authoritative set of
Keplerian ephemeris parameters is used to predict look angles.

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Weather Calm Clear Sky Conditions Operational Winds 44.7 gusting to 55.9
STEP TRACK mph
9.4 m Performance Ka- Mount Motion Mount Motion
SRT SRT
band Dist Type Drives Drives
RMS Peak RMS Peak RMS Peak RMS Peak

Feedback Quantization Constant 0.0004 0.0007 0.0000 0.0000 0.0004 0.0007 0.0000 0.0000
Deadband Constant 0.0017 0.0030 0.0006 0.0010 0.0017 0.0030 0.0006 0.0010
Tracking Lag Sinusoidal 0.0031 0.0044 0.0031 0.0044 0.0031 0.0044 0.0031 0.0044
Scintillation Noise Gaussian 0.0033 0.0098 0.0033 0.0098 0.0033 0.0098 0.0033 0.0098
Wind Induced Error Gaussian 0.0013 0.0039 0.0013 0.0039 0.0013 0.0039 0.0013 0.0039
Variable Tracking Error Mixed 0.005 0.010 0.005 0.010 0.005 0.010 0.005 0.010

Gust Deflection Gaussian 0.000 0.000 0.000 0.000 0.007 0.020 0.007 0.020

Total Variable Error Mixed 0.005 0.010 0.005 0.010 0.008 0.021 0.008 0.021

Scan Loss Absolute 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011

Total Angular Error deg 0.012 0.015 0.012 0.014 0.014 0.023 0.013 0.023

DL Signal Loss dB 0.15 0.22 0.14 0.21 0.19 0.57 0.19 0.56
% of HPBW 11.0% 13.6% 10.9% 13.4% 12.6% 21.7% 12.5% 21.7%

UL Signal Loss dB 0.33 0.50 0.32 0.48 0.43 1.27 0.42 1.27
% of HPBW 16.5% 20.4% 16.4 20.0% 18.9% 32.6% 18.7% 32.5%

TABLE 3 STEP TRACK SYSTEM PERFORMANCE

Weather Calm Clear Sky Conditions Operational Winds 44.7 gusting to 55.9
MEMORY TRACK mph
9.4 m Performance Ka- Mount Motion Mount Motion
SRT SRT
band Dist Type Drives Drives
RMS Peak RMS Peak RMS Peak RMS Peak

Feedback Quantization Constant 0.0004 0.0007 0.0000 0.0000 0.0004 0.0007 0.0000 0.0000
Feedback Repeat. Gaussian 0.0033 0.0100 0.0003 0.0010 0.0033 0.0100 0.0003 0.0010
Deadband Constant 0.0017 0.0030 0.0006 0.0010 0.0017 0.0030 0.0006 0.0010
Prediction Error Gaussian 0.0023 0.0069 0.0023 0.0069 0.0023 0.0069 0.0023 0.0069

Total Tracking Error Mixed 0.004 0.012 0.002 0.007 0.004 0.012 0.002 0.007

Wind Deflection Gaussian 0.000 0.000 0.000 0.000 0.018 0.054 0.018 0.054

Total Angular Error deg 0.004 0.012 0.002 0.007 0.019 0.055 0.018 0.055

DL Signal Loss dB 0.02 0.15 0.01 0.05 0.36 3.18 0.34 3.09
% of HPBW 4.1% 11.0% 2.2% 6.4% 17.3% 51.5% 16.9% 50.8%

UL Signal Loss Db 0.05 0.33 0.01 0.11 0.81 7.16 0.77 6.96
% of HPBW 6.2% 16.6% 3.4% 9.7% 25.9% 77.3% 25.4% 76.2%

TABLE 4 MEMORY TRACK SYSTEM PERFORMANCE

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Weather Calm Clear Sky Conditions Operational Winds 44.7 gusting to 55.9
MONOPULSE mph
9.4 m Performance Ka- Mount Motion Mount Motion
SRT SRT
band Dist Type Drives Drives
RMS Peak RMS Peak RMS Peak RMS Peak

Feedback Quantization Constant 0.0004 0.0007 0.0000 0.0000 0.0004 0.0007 0.0000 0.0000
Deadband Constant 0.0017 0.0030 0.0006 0.0010 0.0017 0.0030 0.0006 0.0010
Tracking Lag Sinusoidal 0.0023 0.0032 0.0023 0.0032 0.0023 0.0032 0.0023 0.0032

Variable Tracking Error Mixed 0.003 0.004 0.002 0.003 0.003 0.004 0.002 0.003

Gust Deflection Gaussian 0.000 0.000 0.0000 0.0000 0.007 0.020 0.007 0.020

Total Variable Error Mixed 0.003 0.004 0.002 0.003 0.007 0.018 0.007 0.018

Bias Error Absolute 0.002 0.002 0.002 0.002 0.002 0.002 0.002 0.002

Total Angular Error deg 0.004 0.005 0.003 0.004 0.007 0.019 0.007 0.019

DL Signal Loss dB 0.01 0.02 0.01 0.02 0.06 0.36 0.05 0.36
% of HPBW 3.3% 4.6% 3.0% 3.7% 6.9% 17.3% 6.7% 17.3%

UL Signal Loss dB 0.03 0.06 0.02 0.04 0.13 0.81 0.12 0.81
% of HPBW 5.0% 6.8% 4.4% 5.6% 10.4% 25.9% 10.1% 25.9%

TABLE 5 MONOPULSE SYSTEM PERFORMANCE

1.1.8 Environmental Controls
1.1.8.1 Dehydration Subsystem

The dehydration subsystem will use the ETI ADH NETCOM automatic dehydrator. This
automatic dehydrator supplies low pressure dry air to keep waveguide and coaxial cable dry.
“Snap On” type air leakage valves will be implemented along with quick release couplings
Norgren Series 233 with type G ¼ connection for monitoring and testing the system. For
easier management, operation, and maintainability this unit will be housed in an outdoor
rated unit mounted on the antenna pedestal and will incorporate an Ethernet interface for
integration to the M&C System.

1.1.8.2 Plenum Based Environmental Management

To help manage thermal distortion the 9.4m antenna subsystem can be integrated with a
reflector enclosing plenum system. Normally reserved for colder climates with significant
snowfall, this system has been designed to “manage” ambient temperature within the
plenum behind the reflector by monitoring multiple points behind the reflector sense
temperature differentials and responding as needed. These techniques result in a more
uniform ambient temperature around the reflector. This management results in more
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1.2 G/T Analysis
A detailed analysis of the Gateway G/T has been performed. The detailed worksheet appear
in Appendix C, and are summarized in the Table below. Ka Band G/T analysis is differs from
Ku or C Band analysis due to monotonically increasing noise temperature with frequency due
to the atmospheric absorption characteristics. This phenomenon is presented in the
antenna’s noise temperature Table of values below.

Antenna Temp (K)
ELEVATION
FREQ (GHz)
ANGLE (deg) 20.2 20.7 21.2
5° 172 184 195
10° 141 150 159
20° 120 124 128
30° 107 11 112
40° 104 106 108
50° 101 102 104
TABLE 6 9.4M NOISE TABLE

The G/T is degraded by tracking error, wind deflection and optical deformation and at Ka
Band it is very important to consider solar defocusing. All antennas, no matter their design,
are affected by solar defocusing to some extent. ASC has carefully characterized this
degradation and has devised an industry unique form of mitigating this inherent gain
reduction characteristic by adding a “Z-Axis” to the optics which effectively corrects the
effects of solar optical distortion. Without the “Z-Axis” correction, an antenna can and does
lose up to 1.4 dB of receive gain (even extremely robust structural designed antennas) in the
presence of intense solar radiation. The ASC SRT Z-Axis correction reduces the solar
defocusing affect to less than 0.25 dB! This is a critical element to consider when analyzing
overall Gateway Terminal performance both at Transmit and Receive.

The following Table summarizes the G/T calculated for three various environmental
conditions and for three separate hardware configurations. The three configurations are: (1)
SRT Step Track, (2) SRT Mono Pulse, and (3) Mono Pulse Mount Motion. The three
environmental conditions are: (1) Ideal Conditions, i.e., no wind and no sun, (2) Solar Defocus
and no wind, and (3) Solar Defocus and wind simultaneously. The take-a-way from this data is
simply that Mono Pulse tracking buys very little return for its complexity and cost and by
mitigating the solar defocusing rather substantial gains are made. The data in the data is a
little more meaningful when see graphically as illustrated in the following chart.

The proposed antenna and tracking system design affords a cost effective and less complex
engineering solution that achieves a G/T within a small variance from the specification!

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ANNEX 2: DRAWINGS

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Document Created: 2015-12-21 14:20:24
Document Modified: 2015-12-21 14:20:24

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