In-Orbit Test of A Satellite Communication Payload

In-Orbit Test of A Satellite

Communication Payload

Albert Lin, (310) 416-3648, albert.y.lin@boeing.com

Shawn Struc, (310) 335-6335, shawn.m.struc@boeing.com

Toni Spiteri, (310) 662-9576, toni.m.spiteri@boeing.com

Boeing Space & Intelligence Systems

El Segundo, CA

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Communication Payload In-Orbit (PIOT)

Test Objectives …

 Verify payload and antenna subsystem health post launch

• Tests are conducted in the on-station configuration to ensure payload hardware has not been degraded by exposure to launch, transfer orbit, deployments, and on-station environments

• Trend PIOT measurements using factory system test as a baseline in either a pre-coordinated test longitude or spacecraft operational longitude

• Perform on-orbit antenna far-field measurements to validate coverage performance and alignment, by comparing with factory test near field or modeled pattern data

• Measure and validate phased array calibration baseline (satellitedependent)

• Prepare for handover to customer or End-To-End system validation

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Mission Description …

 Payload Initialization

 Antenna Phased Array / Beacon Calibration

 Antenna Mapping

 Repeater and Telemetry and Command Test

 Antenna Alignment Adjustment

 Handover Configuration

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Payload Architecture Scope

 Analog “Bentpipe” Repeater Payloads

• BSS/FSS repeaters

• Spot beam repeaters

 Digital Communication Payloads

• Geo-mobile satellites

• On-board digital processing and packet switching

• Phased array antenna

 Satellite Telemetry and Command RF subsystem

• Command receivers and telemetry transmitters

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Typical Communication PIOT Setup

Ground Beacon

External

Interfaces

C-Band Antenna

Network Ku-Band Antenna

T1-Network

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Network

Spacecraft

Command and

Telemetry

Antenna

Mission Control

Center

PIOT Flow/Life Cycle

Select Beams for Mapping

Antenna

Mapping Test

Procedure

Requirement

Flow Down

IOT Test Plan

Test

Sequence

Definition

Test Config

Definition

Payload

Tests

Payload Test

Procedure

PIOT Design

Review

Test

Execution

Data Analysis Handover

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Test Design

 Payload Configuration

 Antenna Mapping

 Communication Payload Tests

 Array Calibration

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Payload Configuration

 Purpose

• Command payload units on and confirm appropriate telemetry responses

 Approach

• Configure to trend factory data

– Redundant o Demonstrate health of redundant hardware not used in nominal on-station configuration o Redundant testing performed prior to primary testing to minimize power cycling of units

– Primary o Demonstrate performance of primary operational hardware prior to handover

– Final Handover o Final configuration required for transition to next test phase or customer operation

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Antenna Mapping

 Purpose

• Demonstrate functional integrity

• Beam forming capability (for payload with array antenna)

• Determine antenna subsystem alignments via spacecraft slews and

RF measurements

• Adjust antenna alignment if necessary

 Approach

• Slewing spacecraft

• Measure at different spots on the ground

 Beam Selection

• Broad/Global Beam

– Cut Example

• Spot Beam

– Cut Example

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Typical Communication PIOT Tests

 Purpose

• Demonstrate health of all payload units via RF measurements

 Approach

• Use standard test types as factory to characterize performance for data trending

– Passband flatness

– Effective Isotopic Radiated power (EIRP)

– Power control

• Build in flexibilities and limitations into test flow

– Account for environment such as weather and unexpected outside factors

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Phased Array Calibration

 Purpose

• Iterative optimization demonstrates calibrated phased array antenna is within specified performance residual accuracy in phase and amplitude

 Approach

• Array calibration is performed and demonstrated on the ground during factory testing, but residual near-field testing errors remain

• Diurnal testing performed during PIOT to confirm antenna performance stability over a 24-hour period

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

PIOT Preparation

 Site Survey

• Ground Antenna System Interface

– Field of View Blockage

– Frequency allocation/coordination

• Antenna Hub Interface

– RF and mechanical interface

• Installation Considerations

– Building permit for remote installation

– IOT equipment location and cable routing

 Ground Station Characterization

• Instrument calibrations required for absolute power measurements

• Verify ground station has sufficient measurement capability

– Ground station performance on G/T, EIRP, uplink and downlink dynamic range, passband response

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

PIOT Preparation

(cont)

 Test hardware and software

• Equipment can be assembled and verified prior to deploying to PIOT ground station to reduce test setup issues

 Rehearsal

• Payload commanding scripts and IOT procedures

 Training

 Coordination with other spacecraft subsystems required

 Risk Mitigation Tests

• Subsystem tests

– Stand-alone test equipment

– Network and communication links

• Software simulations

• Ground testing against spacecraft in factory

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

PIOT Logistics

 Logistic Operation /Customer Interactions

• Provide sufficient workspace

– PIOT team requires adequate location for test measurements and analysis

– Presentation space required for customer data reviews

 Team Communication Plan

• Schedule Flexibility

– Dynamic schedule changes to accommodate customer needs and other mission subsystems as well as unexpected events such as weather

– Alternative tests can be identified as a backup plan

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.

Conclusion …

 Payload IOT process has been proven over 17 years

 Continue to improve and evolve for more complex payloads and to maintain high performance standard

Preparation and rehearsal are the keys to success!

BOEING is a trademark of Boeing Management Company.

Copyright © 2011 Boeing. All rights reserved.