Slide 1Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Spaceborne GNSS at DLR/GSOC

O.MontenbruckGerman Space Operations Center, DLR

Slide 2Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Organization

� Köln -Porz

� Lampoldshausen

� Stuttgart

� Oberpfaffenhofen

Braunschweig �

� Göttingen

Berlin- - �Adlershof

� Bonn

�Trauen

� Hamburg

� Neustrelitz

Weilheim �

Berlin-Charlottenburg �

� Sankt Augustin

� Darmstadt

Bremen �

DLR (German Aerospace Center)Aeronautics, astronautics, energy, and transport research

National Space Agency

~5100 employees in 28 institutes

9 centers, 7 field offices

German Space Operations CenterLocated at Oberpfaffenhofen(25 km west of Munich)

Control center for unmanned and manned space missions

GNSS Technology & NavigationSpaceborne GNSS

Receiver design and testing

Autonomous navigation systems

Formation flying

Slide 3Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Facilities

Control room

(Columbus)

GSOC Oberpfaffenhofen

Weilheim

ground station

Galileo control center

EAC, MORABA, MUSC

Slide 4Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Research Areas

ReceiverTechnology

Autonomous Formation

FlyingPrecision

Navigation

Slide 5Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Roadmap Receiver Techology

2005 2009 2013

Phoenix Miniature GPS

Low Budget Science Receivers

Embedded Real-Time Navigation

2007 2011

Software Defined GNSS Receiver

„Affordable access to spaceborne GNSS technology“

Receiver Performance Assessment

Sentinel-3SHEFEX-2

PROBA-2

Namuru

GNSS Reflectometry

ACES

GNSS Reflectometry

Receiver and Navigation System Support

Slide 6Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Phoenix GPS Receiver

SigTech MG5001 board

75 x 50 x15 mm

0.8W @ 5V regulated

14 krad total ionization dose

DLR tracking s/w for LEO satellites and sounding rockets

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C/N0 [dB-Hz]

Mea

sure

men

t No

ise

Carrier Phase [mm]Pseudorange [m]Doppler [m/s]

Slide 7Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Mission Highlights

X-Sat (NTU, 2009) ARGO (NSPO, 2011)

PROBA-2 (ESA, 2009) Flying Laptop (TU Stuttgart, 2010)

TET (DLR, 2010)

MASTCOMPASS1

Slide 8Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Phoenix-XNS (eXtended Navigation System)

Real-time Kalman filtering of GPS raw measurements

Ionosphere-free C1+L1 combination

Operates inside ARM7TDMI micro-processor of Phoenix receiver

Example400 km LEO orbit, 10 TECU VTEC, 1.5m UERE ephemeris errors

0.5-1 m 3D rms error

Slide 9Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Testing of Spaceborne GNSS Receivers

Signal Simulator

Thermal Vacuum Chamber

Co-60 Source

Proton CyclotronShaker

Slide 10Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Roadmap Formation Flying & On-Orbit Servicing

2009 20132007 20112005

DGPS Navigation

Impulsive Orbit Control

Mission Demonstrations

Self-contained Navigation Systems (RF, optical)

Optimum Distributed Orbit & Attitude Control

PRISMA TANDEM-X

PROBA-3 ?

EPOS ARDOS

Camera Based NavigationDEOS

SMART-OLEV

AutonomousFormation

Flying

On-OrbitServicing

„Innovative GN&C concepts for multi-satellite missi ons“

GNC-System Support, Parameter Identifcation

Contact Dynamics

Slide 11Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Autonomous Formation Flying – PRISMA (2009)

SSC & Partners

Demonstration RVD & Formation Flying

Validation of Sensors,Actuators, Avionics

Launch 2009

TARGET

MAIN

Radio Link

L1 GPS Code & Phase

MAIN

TARGET

Real-TimeNavigation System

Phoenix GPS Receiver

Phoenix GPS Receiver

Slide 12Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

SAR-Interferometry –TanDEM-X (2009)

Orbit Control

e/i-vector separation

Passive safety

Reproduction of TSX maneuvers

Relative Navigation

IGOR GPS Receiver

1 mm accuracy

TAFF Experiment

Intersatellite Link

Real-Time Navigation

Autonomous Control

GPS Time [hours] since 2003/07/29 00:00

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02468

10Std.Dev.: 0.72mm

GPS Time [hours] since 2003/08/04 00:00G

PS

− K

BR

[mm

]

Slide 13Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Roadmap Precision Navigation

2005 2009 2013

GPS based LEO POD, Near-Real-Time POD

Differential GPS Navigation of LEO Satellites

Real-Time GNSS clock products

2007 2011

„High Precision Navigation Services for Future Space Missions“

Galileo Signal Analysis & Data Processing

Sentinel, MetOp, SEOSAR

CONGO GNSS Receiver Network

Slide 14Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

TanDEM-X Precision Baseline Reconstruction

Identical set of IGOR GPSreceivers on both s/c

Absolute orbits ~5cm 3D rms position accuracy

2.5 cm 3D rms DLR-AIUB

1.5 cm SLR residuals (10°elev)

TDX-TSX position difference ~1-2 cm

Relative navigation based on dual-frequency CDGPS

Kalman filter/smoother

Single differenced measurements

Single- or dual-frequency processing

Slide 15Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

GIOVE-A Signal Analysis (2006)

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Slide 16Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Cooperative Network for GIOVE Observation (DLR/BKG)

operational under construction

Concepcion

Mauii

HartebeesthoekSydney

Bangalore

ChofuFredericton Wettzell

Slide 17Space Geodesy Station Workshop > Matjiesfontein > 16 - 20 March 2009

Collaboration Options

Technical

GNSS real-time network setup (NTRIP) and utilization (clocks, iono,integrity)

SLR based orbit determination of GNSS satellites

SLR/GNSS cross-comparison for LEO satellites

Networking

Satellite Geodey at TU Munich (Urs Hugentobler) and Wettzell Station (GNSS, SLR, LRR, VLBI)

Zimmerwald Observatory (Werner Gurtner)

GALILEO project (???)