Attachment Narr and Tech App SAT-MOD-20110929-00192

Attachment Narr and Tech App

This document pretains to SAT-MOD-20110929-00192 for Modification on a Satellite Space Stations filing.

IBFS_SATMOD2011092900192_919154

Before the
FEDERAL COMMUNICATIONS COMMISSION
Washington, D.C. 20554

In the Matter of Application of )
)
SES AMERICOM, INC. ) File No. SAT-MOD-___________
) Call Sign S2156
For Modification of the AMC-5 License to )
Assign the Satellite to 80.9º W.L. with )
+/- 0.1 Degree East-West Stationkeeping

APPLICATION OF SES AMERICOM, INC.

SES Americom, Inc. (doing business as “SES”) hereby requests modification of

its license for the AMC-5 Ku-band fixed-satellite space station to reassign the spacecraft to

80.9° W.L. with an east-west stationkeeping tolerance of +/- 0.1 degrees. Specifically, SES

requests authority to perform telemetry, tracking and command (“TT&C”) in order to relocate

AMC-5 from 79.1º W.L. to 80.9º W.L. and authority to operate both the TT&C and Ku-band

communications payloads on AMC-5 after it has arrived at 80.9º W.L. SES will operate AMC-5

at 80.9º W.L. in accordance with the International Telecommunication Union (“ITU”) filings of

the Argentine Administration. Grant of the requested authority will serve the public interest by

allowing SES to make efficient use of the AMC-5 spacecraft to respond to customer demand and

provide service to the United States from a location where no service is currently being provided.

A completed FCC Form 312 is attached, and SES incorporates by reference the

technical information previously provided in support of AMC-5.1 In addition, SES is providing

here technical information relating to the proposed modification on Schedule S and in narrative

form pursuant to Sections 25.114 and 25.116 of the Commission’s Rules.
1
See File Nos. SAT-MOD-20110714-00126; SAT-MOD-20100706-00154; SAT-MOD-
20050609-00117; & SAT-MOD-19980113-00002.

MODIFICATION

AMC-5 is a Ku-band only spacecraft launched in 1998 that is currently authorized

to operate at 79.10º W.L. with an east-west stationkeeping tolerance of +/- 0.1 degrees.2 SES

also operates the AMC-2 C/Ku-band hybrid spacecraft at the nominal 79º W.L. orbital location.3

SES has proposed to relocate AMC-2 to the nominal 5º E.L. orbital location and to operate it

there pursuant to Swedish licensing authority.4 In preparation for the proposed relocation, SES is

in the process of transitioning all customer traffic off of AMC-2.5 AMC-5 currently serves only

as an in-orbit spare for the Ku-band capacity of AMC-2.

SES now has an opportunity to redeploy AMC-5 to provide service from a new

orbital location. Specifically, SES has entered into an agreement with Empresa Argentina de

Soluciones Satelitales S.A. (“AR-SAT”), which holds an authorization from the Argentine

Government to operate a satellite at the nominal 81º W.L. orbital location.6 That agreement

2
See File No. SAT-MOD-20110714-00126, grant-stamped Sept. 14, 2011 (“September
Modification Grant”).
3
See File No. SAT-MOD-20100324-00056, grant-stamped June 21, 2010.
4
See File No. SAT-T/C-20110527-00100 (“AMC-2 5º E.L. Application”).
5
See id., Narrative at 3. Subject to the receipt of Commission authority, SES proposes to
return AMC-2 to the nominal 79º W.L. orbital location following the successful launch and
commencement of operations of the SES-5 satellite at 5º E.L. See Letter of Karis A. Hastings,
Counsel for SES Americom, Inc., to Marlene H. Dortch, Secretary, Federal Communications
Commission, File No. SAT-T/C-20110527-00100, dated Aug. 19, 2011 at 4-5.
6
Evidence of AR-SAT’s authority is already on file with the Commission. See PanAmSat
Licensee Corp., File No. SAT-STA-20100402-00063 (“Intelsat 3R STA”) at Attachment 2. See
also Letter from the Argentine Ministry of Communications to Joslyn Read of SES dated
Sept. 21, 2011, attached hereto as Annex 1 (confirming that the AR-SAT authorization remains
in full force and effect).

2

provides for operation of AMC-5 at 80.9º W.L. pursuant to the ITU filings of the Argentine

Administration.7

Grant of the requested authority to relocate and operate AMC-5 will serve the

public interest and is consistent with Commission precedent. The Commission has repeatedly

observed that its policy is to allow “satellite operators to rearrange satellites in their fleet to

reflect business and customer considerations where no public interest factors are adversely

affected.”8 As the International Bureau has explained:

the Commission attempts, when possible, to leave
spacecraft design decisions to the space station licensee
because the licensee is in a better position to determine how
to tailor its system to meet the particular needs of its
customers. Consequently the Commission will generally
grant a licensee’s request to modify its system, provided
there are no compelling countervailing public interest
considerations.9

Here, the proposed change will allow SES to make efficient use of AMC-5, a

spacecraft which is not currently providing service, in order to respond to customer demand for

capacity at a new orbital location. Because AMC-5 is now serving as an in-orbit spare, the

7
See Letter from N. Pablo Tognetti of AR-SAT to Joslyn Read of SES dated Sept. 20,
2011, attached hereto as Annex 2 (confirming that AR-SAT is authorized to operate a satellite at
80.9º W.L. and has agreed to permit operation of AMC-5 at that location).
8
SES Americom, Inc., Order and Authorization, DA 06-757 (IB rel. Apr. 7, 2006) at 4, ¶ 8,
citing Amendment of the Commission’s Space Station Licensing Rules and Policies, Second
Report and Order, 18 FCC Rcd 12507, 12509, ¶ 7 (2003).
9
AMSC Subsidiary Corp., Order and Authorization, DA 98-493, 13 FCC Rcd 12316 (IB
1998) at 12318, ¶ 8 (footnote omitted). Although AMSC never implemented the relocation
authorized in this case, the Commission has repeatedly reaffirmed its policy of allowing
licensees to change their fleet configurations to accommodate customer requirements. See, e.g.,
Space Station Licensing Rules and Policies, First Reconsideration Order and Fifth Report and
Order, FCC 04-147, 19 FCC Rcd 12637, 12653, ¶ 39 (“we generally permit licensees to modify
their systems to adapt to changing business and customer needs,” citing AMSC Subsidiary Corp.
and other cases).

3

relocation of the satellite will not have any impact on service at the nominal 79º W.L. orbital

location. The Commission has previously authorized other U.S.-licensed satellites to operate at

the nominal 81º W.L. orbital location pursuant to the Argentine Administration’s ITU filings.10

Reassignment of AMC-5 to 80.9º W.L. +/- 0.1 degrees will not adversely affect

other operators. The proposed stationkeeping volume does not overlap with that of any other

spacecraft.11 SES will operate only the TT&C frequencies of AMC-5 during the drift.12 There

are no satellites located in the proposed drift path at present, so coordination of the TT&C

transmissions during the drift will not be required.

Once AMC-5 arrives at the nominal 81º W.L. orbital location, SES will operate

the satellite in conformance with Argentina’s coordination agreements regarding that location.

The Technical Appendix demonstrates that the AMC-5 network is compatible with a co-

coverage, co-frequency satellite, spaced two degrees away. Here, the adjacent operational Ku-

band satellites on either side of the 81° W.L. position are both licensed to SES (AMC-2 at

79W.L. and AMC-9 at 83W.L.), facilitating any necessary coordination. The proposed

10
See Intelsat 3R STA, grant-stamped Aug. 3, 2010 (authorizing operation of Intelsat 3R at
81.0° W.L. for a period of 180 days pursuant to Argentine ITU filings); PanAmSat Licensee
Corp., SAT-STA-20070308-00044, grant-stamped Apr. 24, 2007 (authorizing operation of
Galaxy 17 spacecraft at 81.0° W.L. for a period of 21 days).
11
The satellite previously positioned at 81° W.L., Intelsat 3R, has been deorbited. See
Letter of Susan H. Crandall, Assistant General Counsel, Intelsat Corporation, to Marlene H.
Dortch, Secretary, Federal Communications Commission, dated August 24, 2011 (notifying the
Commission that pursuant to authority granted in File No. SAT-STA-20110503-00083, Intelsat
completed end-of-life maneuvers for Intelsat 3R on August 17, 2011).
12
The AMC-5 TT&C frequencies are as follows:
Command: 14001 (vertical polarization; uplink)
Telemetry: 11701 and 11702 (horizontal polarization; downlink).

4

modification does not alter the end-of-life disposal plan for AMC-5, which has already been

approved by the Commission.13

SES requests continued waiver of Section 25.210(j) of the Commission’s rules in

connection with the instant Modification.14 That rule specifies that geostationary space stations

“must be maintained within 0.05º of their assigned orbital longitude in the east/west direction,

unless specifically authorized by the Commission to operate with a different longitudinal

tolerance.”15 Grant of a waiver to permit an expanded stationkeeping tolerance of

+/- 0.1 degrees will result in fuel saving that will prolong the AMC-5 spacecraft’s life.

Furthermore, there will be no adverse effect on other operators. At 80.9º W.L., just as at 79.10°

W.L., there is no overlap of the proposed stationkeeping volume with that of any other satellite.

There will likewise be no material effect on the interference environment, and SES will be able

to manage the coordination internally because it operates the Ku-band satellites on either side of

80.9º W.L.

13
See File No. SAT-MOD-20100706-00154, grant-stamped Jan. 20, 2011, Attachment to
Grant at ¶¶ 5-6.
14
See September Modification Grant, Attachment to Grant at ¶ 1.
15
47 C.F.R. § 25.210(j).

5

CONCLUSION

For the foregoing reasons, SES requests that the Commission modify the AMC-5

license to specify operations at 80.9º W.L. +/- 0.1 degrees pursuant to the ITU filings of

Argentina.

Respectfully submitted,

SES AMERICOM, INC.

By: /s/ Daniel C.H. Mah

Of Counsel Daniel C. H. Mah
Karis A. Hastings Regulatory Counsel
SatCom Law LLC SES Americom, Inc.
1317 F Street, N.W., Suite 400 Four Research Way
Washington, D.C. 20004 Princeton, NJ 08540
Tel: (202) 599-0975

Dated: September 29, 2011

6

ANNEX 1:

Letter from the Argentine Ministry of Communications to
Joslyn Read of SES dated Sept. 21, 2011

ANNEX 2:

Letter from N. Pablo Tognetti of AR-SAT to
Joslyn Read of SES dated Sept. 20, 2011

ATTACHMENT A

TECHNICAL APPENDIX

IN SUPPORT OF AMC-5 (80.90W.L.)

1

TECHNICAL APPENDIX

1.0 Overall Description
SES Americom, Inc. (doing business as “SES”) hereby seeks a modification of the license for
AMC-5, call sign S2156, to relocate the satellite to 80.90° W.L. with an east-west stationkeeping
tolerance of +/- 0.1 degrees and operate the communications payload at that position. AMC-5 is
a Ku-band communications satellite, with uplinks at 14.0-14.5 GHz and downlinks at 11.7-
12.2 GHz. At 80.90° W.L., AMC-5 will have coverage of the Continental U.S., parts of Alaska,
Canada and the Caribbean. Table 1 shows the frequency plan of the satellite. The frequency
bands are divided into 16 Ku-band linearly-polarized transponders of 54 MHz bandwidth each.
AMC-5 will be operated in inclined mode.
Only a change in the orbital location of AMC-5 is sought; the other technical parameters of the
satellite remain unchanged. However, because the original documents submitted to the FCC to
describe AMC-5 were filed more than a decade ago, SES is providing for the Commission’s
convenience a more extensive Technical Appendix and Schedule S than would otherwise be
required for a modification application. See 47 C.F.R. § 25.117(d)(1) (requiring submission of
“only those items of information listed in § 25.114 that change”).

2.0 Schedule S

The Schedule S database is attached as an electronic file. The following items supplement the
information provided in Schedule S.
1. Transponder frequency plan.
Sections S9 and S10 of Schedule S show the transponder frequency plans. Beams with IDs
KRV, KTV, KRH and KTH provide coverage over CONUS, Canada, and parts of Alaska.
Transponders K0001 to K0016 connect beams KRV and KTH, and KRH and KTV.
2. TWTA redundancy.
The 16 transponders utilize twenty-two 55 watt TWTA’s arranged in two groups of 11 for 8
redundancy.
3. Inclined orbit operation
AMC-5 will be operated in an inclined orbit with an initial inclination of 1.18 in October 2011
changing at a rate of 0.9 per year.

2

4. Saturation Flux Density values.
SFD values can be obtained by using the expression
SFD = -90 – (G/T) + Transponder Gain Setting, dBW/m2
The minimum SFD values shown in Section 3, column q of the Schedule S are with a gain
setting of 10 dB.
5. Transponder frequency response.
The frequency response and total group delay, specified over the transponder bandwidth, are
provided in Tables 2 to 3 below.
Table 1: Ku-band Frequency Plan
Receive Transmit
Channel Frequency Polarization Frequency Polarization
(MHz) (MHz)
1 14030 H 11730 V
2 14043 V 11743 H
3 14091 H 11791 V
4 14104 V 11804 H
5 14152 H 11852 V
6 14165 V 11865 H
7 14213 H 11913 V
8 14226 V 11926 H
9 14274 H 11974 V
10 14287 V 11987 H
11 14335 H 12035 V
12 14348 V 12048 H
13 14396 H 12096 V
14 14409 V 12109 H
15 14457 H 12157 V
16 14470 V 12170 H

Table 2: Ku-band Transponder Frequency Response
Frequency Offset (MHz) dB p-p
±15 1.0
54 MHz channel ±21 1.6
±27 3.5

Table 3: Ku-band Transponder Total Group Delay
Frequency Offset (MHz) Relative Group Delay
(ns p-p)
±9 6.5
±15 10.5
54 MHz channel
±21.6 21
3

Table 6: Telemetry Link Budget

EIRP, dBW 17
Carrier bandwidth, MHz 0.5
EIRP density, dBW/4kHz -3.97
Tx ES dia (typical), m 5.7
Rx ES antenna gain, dB 55.0
Rx ES G/T, dB/K 33.2
Rain fade, dB 8
CNR, dB 11.1
CNR (required), dB 9
Margin, dB 2.1

3.0 Satellite Antenna Gain Contours

Annex 1 shows the antenna gain contours for 4 different cases: transmit and receive beams in H-
and V-polarizations. Table 7 shows the correspondence between peak gains of the antennas and
maximum EIRP or G/T values.

Table 7: Maximum Co-pol Gain, EIRP and G/T Values
H-pol V-pol
Gain (max.), dBi 32.94 33.64
Transmit beam
EIRP (max.), dBW 48.35 49.05
Gain (max.), dBi 34.32 34.3
Receive beam
G/T (max), dB/K 6.58 7.69

These files with co-pol data are also provided as gxt files in Schedule S:

1. KRH.gxt (H-pol, Ku-band receive beam)
2. KTH.gxt (H-pol, Ku-band transmit beam)
3. KRV.gxt (V-pol, Ku-band receive beam)
4. KTV.gxt (V-pol, Ku-band transmit beam)

In addition, section S7 of Schedule S shows the maximum gains of the receive and transmit
antennas, maximum EIRP, and maximum G/T values.

4.0 Emission Designators and Link Budgets

The services provided by AMC-5 will be wide ranging, including digital TV and digital
transmission services. Sample link budgets for these services follow. Table 8 provides the
characteristics of the earth stations used for this analysis and estimated link margins for Ku-band
carriers. Table 9 shows analog TV/FM (emission designator 36M0F3F) link budgets.

5

Table 8: Link Budgets for 7 Typical Links
Digital TV Digital TV Digital TV Digital TV
MCPC MCPC MCP Digital TV MCPC
40 Mbps 32 Mbps 60 Mbps SCPC 56 Kbps 1.544 Mbps 50 Mbps
Parameter QPSK ¾ RS QPSK ¾ RS QPSK ¾ RS QPSK ¾ RS QPSK ¾ RS QPSK ¾ RS 8PSK ⅔ RS
Digital Mod ID D1 D2 D3 D4 D5 D6 D7
Carrier designation 36M0G7W 27M0G7W 54M0G7W 5M00G1W 100KG1W 1M60G1W 36M0G7W
Data Rate (dB-Hz) 76 75 77.8 67.6 47.5 61.9 77
Throughput rate (Mbps) 40 32 60 6 0.056 1.544 50
Symbol rate (Msps) 28.8 22.9 43.6 4.2 0.041 1.117 27.2
Uplinks:
Transmit Power (dBW) 20 20 8.920 8.9 -2 8 20
Transmit Loss (dB) -2.5 -2.5 -2.5 -2.5 -2.5 -2.5 -2.5
Antenna diameter 6.1 6.1 6.1 3.7 1.8 1.8 6.1
Antenna Gain (dBi) 57.3 57.3 57.3 53.0 46.7 46.7 57.3
Ground Station EIRP (dBW) 74.8 74.8 74.8 59.4 42.2 52.2 74.8
Uplink Rain Loss (dB) -2 -2 -2 -2 -2 -2 -2
Free Space Loss (dB) -207 -207 -207 -207 -207 -207 -207
Satellite G/T (dB/K) 3 3 3 3 3 3 3
Boltzmann’s Constant (dBW/K-Hz) -228.6 -228.6 -228.6 -228.6 -228.6 -228.6 -228.6
Eb/N0 (dB) 21.4 22.4 19.6 14.4 17.3 12.9 20.4
Eb/I0 (dB) 18 18 16 16 16 16 18
Total Eb/(N0 + I0) (dB) 16.4 16.7 14.4 12.1 13.6 11.2 16.0

6

Table 8 (cont’d): Link Budgets for 7 Typical Links
Digital TV Digital TV Digital TV
MCPC MCPC MCPC Digital TV Digital TV
40 Mbps 32 Mbps 60 Mbps SCPC 56 Kbps 1.544 Mbps MCPC
QPSK ¾ QPSK ¾ QPSK ¾ QPSK ¾ QPSK ¾ QPSK ¾ 50 Mbps
Parameter RS RS RS RS RS RS 8PSK ⅔ RS
Carrier designation 36M0G7W 27M0G7W 54M0G7W 5M00G1W 100KG1W 1M60G1W 36M0G7W
Downlinks:
Satellite Carrier EIRP (dBW) 47 46 47.0 34.3 18.5 28.5 47
Interference bandwidth (MHz) 36 27 54 5 0.1 1.6 36
Satellite EIRP density (dBW/4KHz) 7.46 7.71 5.70 3.33 4.52 2.48 7.46
Downlink Rain Loss (dB) -3 -3 -3 -3 -3 -3 -3
Free Space Loss (dB) -205.4 -205.4 -205.4 -205.4 -205.4 -205.4 -205.4
Ground station antenna dia, m 1.2 1.2 1.2 2.4 1.2 2.4 2.4
Ground Station G/T (dB/K) 20.9 20.9 20.9 26.9 20.9 26.9 26.9
Eb/N0 (dB) 12.1 12.1 10.3 13.8 12.1 13.7 17.1
C/IM 18 18 18 18
Eb/Imo (dB) 16.6 16.6 16.6 16.6
C/I 15 15 15 15 15 15 15
Eb/I0 (ASI) (dB) 13.6 13.6 13.6 13.6 13.6 13.6 12.3
Eb/I0 (dB) 13.6 13.6 13.6 13.6 13.6 13.6 12.3
Eb/(N0 + I0) (dB) 9.8 9.8 8.0 9.7 9.0 9.7 11.1
Total Up/Down Eb/(N0+Io)(dB) 8.9 9.0 7.1 7.7 7.7 7.4 9.9
Required Eb/N0 5.4 5.4 5.4 5.4 5.4 5.4 7.2
Margin 3.5 3.6 1.7 2.3 2.3 2.0 2.7

7

Table 9: Link Budgets for TV/FM
Analog Mod. ID: A1
Parameter Typical TV/FM link
Carrier designation 36M0F3F
Uplinks:
Transmit Power (dBW) 22
Transmit Loss (dB) -1
Antenna diameter 6.1
Antenna Gain (dBi) 57.3
Ground Station EIRP (dBW) 78.3
Uplink Rain Loss (dB) -2
Free Space Loss (dB) -207
Satellite G/T (dB/K) 3
Bandwidth (dB-Hz) 75.6
Boltzmann’s Constant (dBW/K-Hz) -228.6
C/N, uplink (dB) 25.4
Downlinks:
Satellite Carrier EIRP (dBW) 48.2
Downlink Rain Loss (dB) -3
Free Space Loss (dB) -205.4
Ground station antenna dia, m 1.2
Ground Station G/T (dB/K) 20.9
C/N, downlink (dB) 13.7
C/I ASI (dB) 18
C/Ntot, dB 12.3
Required (dB) 11
Margin (dB) 1.3

5.0 Power Flux Density Limits

No limits are specified by the FCC in the standard Ku-band used in AMC-5.

6.0 Cessation of Emissions

Each TWTA is commandable to apply or remove RF drive of the associated amplifier as
required under § 25.207. Each TWTA can also be commanded on and off, although they are
normally powered for the entire mission, after the satellite arrives on station.

8

7.0 Interference Analysis

Annex 2 shows the results of an interference analysis in a 2-degree spacing environment. Using
C/I metrics, the analysis shows that the interference can be restricted to no more than 6% of the
noise plus interference at threshold.1

8.0 Mitigation of Orbital Debris (§25.114(d)(14)

The information required under Section 25.114(d)(14) of the Commission’s Rules is already on

file with the Commission.2 SES incorporates that information by reference and provides below a

few minor updates to its previous showing.

§25.114(d)(14)(i): Onstation operations as proposed require stationkeeping within a

+/- 0.05 degree E-W control box.

§25.114(d)(14)(ii): The Commission has granted SES a waiver of Sections 25.114(d)(14)(ii) and

25.283(c) of the Commission’s rules in connection with the residual helium that will remain in

the AMC-5 tanks at the end of the spacecraft’s life.3

§25.114(d)(14)(iii): The instant application seeks authority for operation of AMC-5 at the

80.90° W.L. orbital location. SES is not aware of any other FCC- or non-FCC licensed

spacecraft that are operational or planned to be deployed at 81° W.L. or to nearby orbital

locations such that there would be an overlap with the requested stationkeeping volume of AMC-

5.

1
The interference analysis is done assuming digital wanted and interfering carriers. Analog
carriers will be coordinated on a case-by-case basis, and are not addressed here.
2
See File No. SAT-MOD-20100706-00154, Technical Appendix, Section 5.
3
See File No. SAT-MOD-20100706-00154, Call Sign S2156, grant-stamped Jan. 20, 2011,
Attachment to Grant at ¶ 4.

9

ANNEX 1

COVERAGE MAPS

10

ANNEX 2

INTERFERENCE ANALYSIS
IN SUPPORT OF AMC-5

15

Two-degree Spacing Analysis

The operational Ku-band satellites adjacent to the 81° W.L. position are AMC-2 at 79W.L. and
AMC-9 at 83W.L., both of which are licensed to SES. SES will do routine internal coordination to
address interference problems, if any.
In the event that a non-SES satellite is placed at 79W.L. or 83W.L., SES will coordinate with the
other operator in conformance with the FCC’s 2 spacing regulations.
The following analysis will demonstrate that the AMC-5 network is compatible with a co-coverage,
co-frequency satellite, spaced two degrees away. This analysis has been performed for digital
signals in both networks. Analog TV/FM signals are coordinated on a case-by-case basis with
nearby spacecraft, and are therefore not addressed in this analysis. Digital signals are more robust
and operate typically down to much lower C/N ratios than analog signals. They are therefore more
tolerant of interference, improving the ability to coordinate at 2º orbit spacing.
1 Uplink analysis
This scenario addresses uplink interference between digital carriers in both the wanted and victim
satellite networks. The analysis assumes that the transponder gains can be matched to give similar
wanted input signal spectral density levels at the two satellites. The uplink C/I will be a function of
the difference between the gain of the transmitting earth stations at boresight and the gain at the off-
axis (topocentric) angle.
1.1 Uplink C/I estimates
The topocentric angle for a geocentric separation of 2º is approximately 2.2º. The sidelobe
envelope at 2.2º off boresight for an antenna that meets the 29-25 log() reference pattern is
20.4 dBi. The boresight gain will be a function of the size of the transmitting earth station. The
following Table 1 lists the boresight gain, the off-axis gain and the corresponding C/I that would
result in the interference scenario with the 2-neighbor having a G/T disadvantage of -4.0 dB/K.
Table 1: Uplink C/I for 2-degree geocentric spacing
On-axis gain
Antenna size (m) (dBi) Off-axis gain C/I (dB)
1.2 43.19 20.44 18.75
1.8 46.71 20.44 22.27
2.4 49.21 20.44 24.77
4.5 54.67 20.44 30.23
6 57.17 20.44 32.73

16

Assuming that the minimum (i.e., threshold) C/N for a digital service is 8 dB, the effect of the C/I
(18.75 dB) from the 1.2 meter earth station in Table 1 above would only degrade the C/N by
0.35 dB, equivalent to an increase of 8.41% in the victim’s system noise temperature. Although this
does exceed the normal criteria of 6% by a small amount, the victim system’s link degradation is
still less than 0.5 dB, which is significantly less than the likely link margin. It may also be noted
that if the G/T disadvantage of the 2-neighbor is -2.0 dB/K the increase in the victim’s system
noise temperature would be 5.3% which is within the normal criteria of 6%.
If the orbital spacing between AMC-5 and a neighbor is 1.9 the C/I values shown in Table 1 will
decrease by an estimated amount of 0.5dB which is not significant. .

2 Downlink analysis
This scenario addresses downlink interference between digital carriers in both the wanted and
victim satellite networks assuming that the EIRP of the two satellites is similar.
The topocentric angle for a geocentric separation of 2º is approximately 2.2º. The gain at 2.2º off
boresight for an antenna that meets the 29-25 log() reference pattern is 20.4 dBi. The boresight
gain will be a function of the size of the receiving earth station.

Table 2: Ku-band downlink C/I for 2-degree geocentric spacing
EIRP of the wanted and interfering satellites is the same

Off-axis gain Off-axis
Antenna size (m) On-axis gain (dBi) C/I (dB)
(dBi) discrimination (dB)
1.2 41.66 20.44 21.22 21.22
1.8 45.18 20.44 24.74 24.74
2.4 47.68 20.44 27.24 27.24
4.5 53.14 20.44 32.70 32.70
6 55.64 20.44 35.20 35.20

Again, assuming that the minimum (i.e., threshold) C/N for a digital service is 8 dB, the C/I values
in Table 2 are higher than the 20.2 dB required to meet the 6% limit. If the orbital spacing between
AMC-5 and a neighbor is 1.9 the C/I values shown in Table2 will decrease by an estimated amount
of 0.5dB which are within the limit required to meet the 6% limit.

17

Engineering Declaration

DECLARATION OF Krish Jonnalagadda

I, Krish Jonnalagadda, hereby certify under penalty of perjury that I am the technically
qualified person responsible for preparation of the technical information contained in the foregoing
exhibit; that I am familiar with the technical requirements of Part 25; and that I either prepared or
reviewed the technical information contained in the exhibit and that it is complete and accurate to
the best of my knowledge, information and belief.

_/s/____________________
Manager, Spectrum Development
SES Americom, Inc.

Dated: September 29, 2011

18

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Document Modified: 2011-09-29 18:30:40

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