Telstar 11N Technical Manual - traveltronic · Telesat Telstar 11N Technical Manual _____ ESD-002...

Telesat Telstar 11N Technical Manual

________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09

This document does not contain export controlled technical data as defined by Directorate for Freedom of Information and

Security Review (DFOISR).

This document shall not be disclosed, disseminated or reproduced, in whole or in part, without the express prior written approval

of Telesat.

Telesat

Telstar 11N

Technical Manual

2008 Edition


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09




of Telesat.

Telesat All rights reserved.

2008 Edition.

Printed in the USA.

Descriptions and content subject to change without notice.

Data contained herein represents typical spacecraft performance. As such, this data is not

transponder-specific and should not be used for detailed, final engineering design of

communications networks using Telstar satellites.

Revision Date Revised

By

Approved

By

Remarks

1.1 Jul 08 Engineering D. Gardner Initial Issue

1.2 Apr 09 Engineering D. Gardner Update to Transponder Frequency Plan


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09




of Telesat.

Table of Contents

Introduction ……………………………………………………………………………… 1

Technical Summary ……………………………………………………………………... 2

Technical Description …………………………………………………………………… 7

Ku-Band Payload Summary ……………………………………………….…………. 7

Connectivity ……………………………………………………….…….……………. 7

EIRP ………………………………………………………………………….……….. 7

G/T …..…………………….……………………………………………………….….. 7

Saturation Flux Density ……………………………………………………………….. 8

Fixed Gain Mode ……….……………………………………………….……………. 8

Automatic Level Control …………………………..…………………………………. 8

Polarization ……….……….……………………………………………….…………. 9

Cross-Polarization Isolation …………………………………………………...…...…. 9

Beacons …..………….………………………………..………………………..…..…. 9

Spacecraft Redundancy …………………………………………………………...…... 10

Appendix A – Supplemental Specifications .…………………………………………… 19


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09




of Telesat.

Figures

Figure 1: Telstar 11N Fully Deployed …………………………………………………….4

Figure 2: Telstar 11N Antenna Configuration …………………………………………….5

Figure 3: Telstar 11N Transponder Frequency Plan ………………………………………6

Figure 4: Telstar 11N Europe Transmit EIRP (dBW) ……………………………………11

Figure 5: Telstar 11N Europe Receive G/T (dB/K) ....……………………………………12

Figure 6: Telstar 11N Africa Transmit EIRP (dBW) ……………………………………..13

Figure 7: Telstar 11N Africa Receive G/T (dB/K) …....…………………………………..14

Figure 8: Telstar 11N US Transmit EIRP (dBW) …...…………………………………....15

Figure 9: Telstar 11N US Receive G/T (dB/K) ...................................................................16

Figure10: Telstar 11N AOR Transmit EIRP 9dBW) ............................................................17

Figure11: Telstar 11N AOR Receive G/T (dB/K) ................................................................18


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09

This document does not contain export controlled technical data as defined by Directorate for Freedom of Information and Security

Review (DFOISR).

This document shall not be disclosed, disseminated or reproduced, in whole or in part, without the express prior written approval of

Telesat.

1

Introduction

Telstar 11N, stationed at the 37.55 degrees West Longitude, expands the scope of Telesat Ku-

band satellite services. The state-of-the-art, high-power Telstar 11N communications satellite

offers increased coverage areas serving Europe/North Africa, North America, the Caribbean,

Atlantic Ocean Region (AOR) and West/South and Sub-Saharan Africa. From payload to

coverage areas, Telstar 11N has been designed to meet the highest performance objectives

including high reliability and a long operating life.

The Telstar 11N satellite operates in three Ku frequency bands. It is a three-axis stabilized

spacecraft based on Space System/Loral’s LS-1300 bus. The high-power bus is able to support

39 Ku-band transponders, with 100 watt Traveling Wave Tube Amplifiers (TWTAs) assigned to

transponders for the US beam, 125 watt TWTAs assigned to transponders within the Europe and

AOR beams, and 150 watt TWTAs assigned to transponders within the Europe, AOR and Africa

beams. The satellite design utilizes high efficiency solar cells and a unique heat-radiating design

to support the high power payload. The spacecraft physical design and layout optimize the EIRP

and G/T performance of the satellite.

The spacecraft structure consists of a large, rectangular main body to internally house the

electronic equipment and externally support the satellite communication antennas, solar arrays

and thrusters. Telstar 11N employs advanced shaped-reflector technology to accurately define

the EIRP and G/T performance contours. This antenna technology allows for optimum

distribution of the satellite power on the earth’s surface plus excellent cross-polarization

performance.

The multiple coverage regions may be interconnected by reconfigurable ground commands.

Eighteen transponders have switchable uplinks and coverage areas, while 21 transponders have

dedicated uplinks and coverage areas. The AOR uplink beam is limited to US downlink only, and

the AOR downlink beam is limited to US uplink only.

The transponders may also provide Automatic Level Control (ALC). ALC allows the

transponder downlink to remain at a fixed operating point during uplink fades. The operating

point can be set at levels between transponder saturation and 5 dB input back-off, offering

significant benefit to all forms of satellite traffic, analog and digital.

There are linearizers on all transponders. The linearizers add gain expansion and phase advance

in order to offset the gain compression and phase lag of the TWTAs.

The Telesat Satellite Management and Control Center, has the most advanced satellite control

earth station equipment available. Telesat continues to lead the industry in providing exceptional

high quality service to its customers.


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Technical Summary

Launch Information

Orbital Location: 37.55 W.L.

Launch Date: 4th

Qtr 2008

Launch Vehicle: Land Launch (Sea Launch rocket from Baikonur)

Life Expectancy: 15 years (operational mission design life)

Transponder Information

Ku-Band Coverage Bandwidth Power

US, Caribbean 54 MHz 100 Watt TWTA

Europe 54 MHz 125/150 Watt TWTA

Africa 54 MHz 150 Watt TWTA

Atlantic Ocean 27 MHz 125/150 Watt TWTA

Station Keeping: 0.05

Pointing Accuracy: 0.13 for normal operations

Satellite Physical Design

Manufacturer: Space Systems/Loral

Spacecraft Bus Design: LS1300

Stabilization Mode: 3-axis stabilized

Structure Dimensions (Stowed): 19.5 x 10.3 x 9.7 ft.

Structure Dimensions (Deployed): 17.9 x 28.5 x 102 ft.

Solar Array Area: 642 ft2

Prime Power (Summer Sol./EOL): 9547 W

Batteries(Two): 24-cell, 80 Ahr, Li-Ion

Eclipse Capability: 100%

Total Mass at Launch: 4010 kg/8820 lbs.

Dry Mass: 1773 kg/3900 lbs.

Satellite Antennas

Ku-Band: US/Caribbean 1 Combined Transmit/Receive

Europe 1 Combined Transmit/Receive

Africa 1 Combined Transmit/Receive

Atlantic Ocean 1 Combined Transmit/Receive

TT&C 4 Telemetry


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Redundancy HPAs LNAs D/Cs

Transponders: 49-for-39 10-for-7 25-for-15

Beacon: 2-for-1


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Fully Deployed

Figure 1


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Antenna Configuration

Figure 2


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Transponder Frequency Plan

Figure 3


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Technical Description

Ku-Band Payload Summary

The Telstar 11N Ku-band communications payload is a mix of 100W, 125W, and 150W TWTAs

operating at 0 dB or 3 dB Output Back Off (OBO) over 39 active transponders operating in

multiple frequency bands. The payload frequency range is 10.95 to 12.75 GHz (downlink), 13.75

to 14.50 GHz (uplink). The useable bandwidth of the transponders for Europe, USA, and Africa

downlink coverage is 54 MHz. The usable bandwidth of the transponders for Atlantic Ocean

downlink coverage is 27 MHz. Transponder center frequencies are shown in the Telstar 11N

Transponder Frequency Plan.

Four beacon frequencies are shown in the frequency plan. The Ku-band transponders can be

individually configured to operate in either the Fixed Gain Mode or the Automatic Level Control

Mode.

Connectivity

The satellite has the ability to connect various uplink combinations to some of the downlink

beams. Other uplink to downlink beam configurations are fixed. The current transponder

connectivity is shown in the frequency plan (Figure 3).

EIRP

The following table summarizes End-of-Life (EOL) at Edge-of-Coverage (EOC) minimum

transponder EIRP performance for the Telstar 11N Ku-band transponders. For more detailed

information, please refer to the EIRP patterns.

Coverage Area Ku-Band Coverage Area Ku-Band

(dBW) (dBW)

Europe 47.0 CAFTA 49.0

West Europe 50.0 Puerto Rico 49.0

AOR 44.0 USA 46.0

West Africa 49.0 Atlantic Off-Shore 45.5

South Africa 48.0 Gulf of Mexico 47.0

Sub-Sahara 46.0 Nova Scotia 43.0

G/T

The following table summarizes minimum G/T values at EOL for the Telstar 11N Ku-band


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

transponders at EOC. For more detailed information, please refer to the G/T patterns.


(dB/K) (dB/K)

Europe 1.0 CAFTA 2.0

West Europe 3.0 Puerto Rico 2.0

AOR -2.3 USA -1.0

West Africa 1.0 Atlantic Off-Shore -1.0

South Africa 0.0 Gulf of Mexico 1.0

Sub-Sahara -2.0 Nova Scotia -3.0

Saturation Flux Density

The following table summarizes the minimum Saturation Flux Density (SFD) values at EOL for

the Telstar 11N transponders at EOC, and are based on 0 dB attenuation @ Fixed Gain Mode.


(dBW/m2) (dBW/m2)

Europe -95.0 CAFTA -97.0

West Europe -97.0 Puerto Rico -97.0

AOR -95.0 USA -94.0

West Africa -96.0 Atlantic Off-Shore -94.0

South Africa -95.0 Gulf of Mexico -96.0

Sub-Sahara -93.0 Nova Scotia -92.0

Fixed Gain Mode

Telstar 11N Ku-band transponders can be individually configured to operate in either the Fixed

Gain Mode or the Automatic Level Control mode. The transponders consist of a Linearized

Channel Amplifier (LCAMP), electronic power conditioner, and Traveling Wave Tube.

In the Fixed Gain Mode (FGM), the transponder’s LCAMP commandable attenuator is used to

control channel gain and, hence, set Saturation Flux Density (SFD). The FGM has a 31 dB

commandable gain range in 1.0-dB steps. The SFD is adjustable separately for each transponder.

Automatic Level Control

The Automatic Level Control (ALC) mode provides automatic onboard compensation for uplink

rain fade. The ALC circuit maintains the output at a constant level in the event of an uplink


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

signal fade. In the ALC mode, a commandable TWTA drive adjust attenuator following the ALC

circuit is provided to adjust the TWTA drive level by a total of 15.5 dB in nominal 0.5 dB steps.

The ALC has up to 21 dB of dynamic range to automatically compensate for uplink fades, while

maintaining the TWTA drive level at the input backoff level specified.

The ALC mode operates according to the average power in the transponder (signals plus noise)

and has a nominal time constant of 50 ms and a minimum constant of 10 ms.

Polarization

All four Ku-band transmit and receive antennas utilize both horizontal and vertical linear

polarization.

Cross-Polarization Isolation

The Ku-band cross-polarization receive isolation is 31 dB minimum.

Beacons

The satellite provides up to four beacons - two beacons radiating in the vertical downlink

polarization and two beacons radiating in the horizontal downlink polarization. The beacon

subsystem consists of four transmitters, with the ability to utilize two dedicated TWTAs to

provide High-Power Wide-Angle telemetry transmission when necessary.

The Telstar 11N Ku-band beacon polarizations and frequencies are shown below:

Downlink Polarization Beacon Frequency

Vertical 11199.25 MHz

Vertical 11699.50 MHz

Horizontal 11198.25 MHz

Horizontal 11698.50 MHz

A minimum of two of the four beacons will be active during “on-station” operations. These

beacons can be used for earth station tracking and earth station antenna polarization alignment.

The beacon stability is +/- 10 ppm (EOL) with an EIRP of >9 dBW at EOC.


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Spacecraft Redundancy

The Telstar 11N satellite design utilizes a variety of redundancy techniques. These techniques

include automatic on-line redundancy and manually switched components. Critical spacecraft

components are redundant as shown in the following table:

Spacecraft Component Redundancy

Ku-band TWTAs: 49-for-39

Ku-band LNAs: 10-for-7

Ku-band D/Cs: 25-for-15


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Europe Transmit EIRP (dBW)

Figure 4


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Europe Receive G/T (dB/K)

Figure 5


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Africa Transmit EIRP (dBW)

Figure 6


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Africa Receive G/T (dB/K)

Figure 7


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N US Transmit EIRP (dBW)

Figure 8


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N US Receive G/T (dB/K)

Figure 9


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N AOR Transmit EIRP (dBW)

Figure 10


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N AOR Receive G/T (dB/K)

Figure 11


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Appendix A

Supplemental Specifications

Group Delay

The following table shows a typical transponder’s group delay at center frequency offsets:

Typical Group Delay 27 MHz

Frequency, offset from center (MHz) +/-6 +/-8 +/-10 +/-12 +/-13.5

Ku-Band Transponders (ns) 10.5 14.5 23.0 50.0 100.0

Typical Group Delay 54 MHz

Frequency, offset from center (MHz) +/-12 +/-16 +/-20 +/-24 +/-27

Ku-Band Transponders (ns) 8.0 11.0 18.0 31.0 60.0

Amplitude Linearity

The level of the third order intermodulation products resulting from two equal carriers in the

same transponder shall not exceed the levels given below, relative to either output carrier.

Input level of each carrier below

single carrier saturation (dB)

Level of third order product at

output (dBc)

3 -9.5

6 -17

9 -22

13 -27

20 -33

Noise Power Ratio (NPR)

The NPR is defined as the ratio of the power density of the noise to the power density in the

center slot at the output of the transponder. The following table shows typical transponder NPR

performance at different noise loading levels:

NPR Performance

Output Back-off (dB) -2.5 -3.0 -3.5

NPR (dB) -13.5 -15.0 -16.5

Phase Linearity

The total phase difference, measured at the transponder output, between a carrier at saturation

compared with a 20 dB input backoff is less than 20 degrees.

Frequency Translation Stability

For Ku-band transponders, the daily stability of the translation frequency is 0.5 ppm. The long-

term stability over the mission life is 2.0 ppm.


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Spurious Outputs

The total power resulting from the sum of all spurious signals measured at the input to the

transmit antenna will not exceed -30 dBW in any 1 MHz band in the frequency range of 10.95 to

12.75 GHz.


________________________________________________________________________

ESD-002 Rev 1.2 07-Apr-09


Review (DFOISR).


Telesat.

Telstar 11N Technical Manual - traveltronic · Telesat Telstar 11N Technical Manual _____ ESD-002...

Documents

Transcript of Telstar 11N Technical Manual - traveltronic · Telesat Telstar 11N Technical Manual _____ ESD-002...