MAPSAR

www.obt.inpe.br/satelite/mapsar

MAPSAR

MAPSAR: a New L-Band Spaceborne Light SAR Mission for Assessment and Monitoring

of Terrestrial Natural Resources

National Institute for Space Research - INPE - Brazil

German Aerospace Center - DLR - Germany

Institute of Lightweight Structures - TU Munich - Germany

MAPSAR

Contents

Motivation

Background

Satellite Concept

Sensor Concept and Performance

Compliance with User Requirements

Current Status

MAPSAR

WORKSHARE PRINCIPLES

INPE PMM

Systems Engineering

Satellite AIT (assembly, integration and test)

SIVAM Airborne Simulation in Brazil

DLR SAR Sensor

Orbit Analysis

ESAR Airborne Simulation in Europe

TUM Reflector Antenna

MAPSAR

MOTIVATION

To verify the feasibility of a satellite on the 500 kg class mission with a Light SAR payload.

To fulfill the requirements for German and Brazilian users for assessment and monitoring of Terrestrial Natural Resources, considering the following themes:

AgricultureCartography Disaster Management Forestry GeologyGeomorphology HydrologyOceanographyUrban studiesDefense/Intelligence

MAPSAR

BACKGROUND

20 years cooperation between INPE and DLR.

Late 90’s: mission proposal from DLR to INPE for Amazon Region observation based on a Light SAR sensor.

July 2001: joint project establishment for system evaluation.

October 2001: users workshop at DLR.

April 2002: users workshop at INPE.

July 2002: Consolidation of user requirements.

December 2002: Pre-phase A conclusion.

December 2003: Phase A study was established (2004-2005 period).

MAPSAR

MAPSAR Workshop April 15, 2002MAPSAR Workshop April 15, 2002 Summary::. Hosted by INPE,. Hosted by INPE,. 83 registered workshop attendees,. 83 registered workshop attendees,. 28 agencies (mainly Brazilian governmental level),. 28 agencies (mainly Brazilian governmental level),. 09 0ral presentations (invited-speakers), 01 Plenary Session,. 09 0ral presentations (invited-speakers), 01 Plenary Session,. Main Application Fields: Agriculture. Main Application Fields: Agriculture CartographyCartography IntelligenceIntelligence Disaster ManagementDisaster Management ForestryForestry GeologyGeology HydrologyHydrology OceansOceans Urban StudiesUrban Studies

MAPSAR

Application/MAPSARparameters

Agriculture CartographyDisaster

(Oil slick/Ship

Monitoring)

Forestry Geology/Geomorphology

Hydrology Oceanography UrbanMapping

Frequency LL

LC

CL

L *, CL

LL

L, CL

CL

LC

Polarization/Polarimetry

quad. polquad. pol

N. E.N. E.

VV, HHquad. pol

quad-pol.quad. pol

HH, HVquad. pol

quad. pol.quad. pol

quad-polquad. pol

quad-polquad. pol

IncidenceInterval

variable25°-45°

variable(45 ° *)(45 ° *)

20°-30°/45°-60°variable

20°-45°20°-45°

large intervallarge interval

20°-45°20°-45°

High (45-60°)(45-60°)

40°-45°variable

SpatialResolution

30 meters3-5 meters

5 meters3-5 meters

30-50/15 m3-5 meters

10 meters10 meters

5 – 10 meters3-5 meters

10 meters3-5 meters

variable(High/Moderate)

(High/Moderate)

5 meters3-5 meters

Swath 30 km30 km

N. A.variable

150-350 kmvariable

100 kmvariable

40-100 Km40-100 Km

100 kmvariable

350 km(ScanSARand FineModes)

variable

40-100 km40-100 km

OrbitInclination

N. A.sun-syn

sun-synsun-syn

sun-synsun-syn

sun-synsun-syn

sun-synsun-syn

sun-synsun-syn

sun-synsun-syn

sun-synsun-syn

LookDirection

N. A.asc/desc

asc/descasc/desc

asc/descasc/desc

N . A.asc/desc

asc/descasc/desc

asc/descasc/desc

N. A.asc/desc

asc/descasc/desc

Revisit 15 days< 15 days

N. A..seasonal

< 1 day< 1 day

monthlymonthly

seasonalseasonal

10 –15days< 15 days

dailydaily

N.A.yearly

Accessto data

real-timereal-time

N. A.regularly

real-timereal-time

N. A.regularly

N. A.regularly

N. A.regularly

real-timereal-time

N. E.regularly

AdditionalRequirement

-InSAR

stereoscopyInSAR (opt.)

-InSAR

-InSAR

stereoscopyInSAR

-InSAR(opt.)

raw dataInSAR

-InSAR(opt.)

(N. A. = Information Not Available, * First priority)

MAPSAR Application User RequirementsBlack - Brazilian User Requirements / Blue - German User

Requirements

MAPSAR

System Constraints

Satellite constraints related to:• mass• power generation• geometric envelope• data rate

Imposed the following limitations:• single band• reflector antenna• max 55 km swath

MAPSAR

MAPSAR Final Application User Requirements

User/MAPSAR parameters

Frequency LPolarization single,dual and quad. pol.Incidence Interval 20°- 45°Spatial Resolution 3-20 metersSwath 20 km - 55 km Orbit Inclination sun-synchronousCoverage globalLook Direction ascending/descending and left/right lookingRevisit weeklyAccess to data near real timeAdditional Requirement InSAR and Stereoscopy

MAPSAR

Mission Baseline

Strong oriented to an operational application system serving “public good” , not excluding scientific and commercial aspects.

Thematic Mapping and Monitoring purposes.

Mission continuation (series of satellites).

MAPSAR

Satellite Concept

– Modularity

– Independent AIT for Payload and Platform modules

– Objectives:

Cost reduction

Shorter schedule

High reliability

MAPSAR

Mapsar in Orbit Configuration

MAPSAR

MMP performance

ACDH:

• Pointing accuracy: < 0.05o (3 σ)• Drift: < 0.001o/s• Attitude determination:< 0.005o (3 σ)• Off pointing of: 30o in 120 seconds

Payload Capability:

• Mass: up to 280 kg• Volume: compatible with class of launchers • Power supply: 175 W average

900 W peak

MAPSAR

MMP Blow-up

MAPSAR

MMP Development Status

• Power Supply, Structure, TT&C and Propulsion subsystems contracted in December 2001.

• PDR (Preliminary Design Review) in May 2003.

• CDR (Critical Design Review) performed in 2004.

• ACDH (Attitude Control and Data Handling) to be contracted.

• Total development at the end of 2007.

MAPSAR

Payload Module

- Limitations imposed by the MMP performance

Mass

Power

ACDH

Envelope

- Functional Block Diagram

- Proposed Configuration

MAPSAR

Mapsar payload functional block diagram

MAPSAR

MAPSAR Payload Module

MAPSAR

MAPSAR -1 (without reflector)

MAPSAR

MAPSAR -1 (without reflector)

MAPSAR

MAPSAR-1 Flight Configuration

MAPSAR

MAPSAR-1 in-orbit top view

MAPSAR

MAPSAR-1 alternative view

MAPSAR

MAPSAR-1 Launcher Class

MAPSAR

MAPSAR Mass Budget

Sub-System Mass [kg]

Mechanical Structure 30.0

Thermal Control 4.0

Radar Sensor & Data Aquisition 193.6

Data Storage & Transmitter 42.5

Total Mass 270.1

Specified Mass 280.0

Nominal Margin + 9.9

MMP 250 kg

MAPSAR total 520.1 kg

MAPSAR

SENSOR CONCEPT AND PERFORMANCE

MAPSAR

Proposed Antenna Concept

Antenna Trade-Off Result:

Elliptical parabolic main reflector

7,5 m length (azimuth)

5 m width (range)

Cassegrain type subreflector

67 cm length (azimuth)

93 cm width (elevation)

Distance to main reflector: 2,8 m.

Feed type: horn antenna

Technology Example:

HALCA (MUSES-B), the first astronomical satellite dedicated to Very-Long Baseline Interferometry (VLBI), was launched from Kagoshima Space Center on February 12, 1997.

Operating frequency 1.6-1.73 GHz

Reflector diameter 8 m

MAPSAR

Design Goals

• Reflector aperture 5 m x 7.5 m, elliptical.

• Shape accuracy 5 mm RMS (TBD).

• Low mass < 2 kg/m2.

• High design flexibility for the range of requirements

(incl. launch and space environment).

• Easy integration of enabling technologies (reflecting

surface, deployment and shape control etc.)

MAPSAR

MAPSAR

Access Region / Field of View

Off-nadir angle

Nadir

Incidence angle

395 km204 km

620 km

20° 48,1°

Current swath is selected by rolling the whole satellite

MAPSAR

Radar Modes

MAPSAR operates three different resolution modes (3m, 10m, 20m) in three

different polarization modes: Single (SPM), Dual (DPM), Quad (QPM).

Overview of important modes:

parameter unit HR ModeHigh Resolution

SPM

MR ModeMedium Resol.

DPM

LR ModeLow Resolution

QPMaccess region near far near far near fargeometric resolutionrangeazimuth

mm

4,73,1

3,13,1

1010

1010

2020

2020

orbit altitude km 620 620 620 620 620 620carrier frequency GHz 1,3 1,3 1,3 1,3 1,3 1,3antenna size height length

mm

57,5

57,5

57,5

57,5

57,5

57,5

off-nadir angle ° 20,0 41,8 20,0 41,8 20,0 32,1incidence angle ° 20,3 47,6 20,0 48,1 20,0 36,8ground swath width km 38,3 20,5 45,1 35 43,4 28polarisation - SPM SPM DPM DPM QPM QPM

MAPSAR

N adir O ffset / km

204 km 599 km395 km

1

2

3

4

5

6

7

8

9

10

20° 48,1°Incidence angle

Radar Beam Specification

beamnumber

/ km

incidenceanglerange

/ °

swathwidth/ km

eff. PRF/ Hz

1 19,93 - 23,95 45,1 26602 23,76 - 27,32 41,9 30103 27,12 - 30,71 44,5 26604 29,69 - 33,31 46,9 26605 32,86 - 36,52 50,4 29106 36,15 - 39,86 54,8 26607 39,50 - 42,69 50,0 29008 42,22 - 45,24 51,0 26409 45,16 - 46,92 31,6 287010 46,28 - 48,08 33,5 2680

Radar Beam specification (Medium/Low Resolution)

SPM, DPM low/medium res. (20/10 m): 31- 55 km swath

SPM high res (3m): 5 - 38 km swath

QPM low res. (20 m): 28 – 43.4 km swath

QPM medium res. (10 m): 22 – 23.3 km swath

MAPSAR

Compliance with User Requirements

MAPSARFrequency L-Band Fully compliant to L-Band

MMP mass and power capability limitations impose single frequency band. Main focus of the users is on L-band frequency. Power requirements in L-band are lower than in C-band and will relax the system design.

Polarization/ Polarimetry

single,dual and quad. pol. Fully compliant

SPM, DPM and QPM are foreseen for all resolution modes. Due to data rate restrictions (300 Mbit/s) swath is adjusted. All modes taking advantage of the full data rate to optimise the system sensitivity with respect to radiometric resolution and NESZ.

Incidence Interval

20°-45° Partially Compliant

The chosen sensor design allows an incidence interval between 20°-48° to minimise the revisit time. Larger incidence angles (60°) would increase the antenna dimension to an unfeasible size.

Spatial Resolution

3-20 meters Fully compliant

Required resolution was obtained with the compromise of the swath width in all polarization modes. Swath 20 km-55 km Partially Compliant

The maximum attained swath width (45 km near range, 55 km middle range and 35 km far range) is restricted either by data rate, antenna beam width or range ambiguities.

Orbit Inclination

sun-synchronous Fully compliant

Look Direction

ascending/descending and right/left looking

Fully compliant

Revisit time weekly Compliant

The height stability has to be kept by manoeuvres. Access to data

near real-time Compliant

InSAR Compliant Further orbit investigations have to be made. Minor orbit manoeuvres are necessary.

Additional Requirement

Stereoscopy

Fully Compliant

MAPSAR

Conclusions

• Pre-phase A study has been completed.

• Preliminary feasibility was demonstrated for reflector antenna concept.

• High interaction with users to define the mission.

• Degree of innovation: 500 kg class SAR satellite, reflector antenna, sensor performance.

• Applications will take advantage of high resolution L-band SAR with enhanced capabilities (polarimetry, stereoscopy, interferometry), particularly suitable for the Amazon region and Boreal forest.

• Critical items: antenna deployment mechanism, solid state high power amplifier.

• Cost estimate 90 MUS$ including launcher.

• Estimated time to deployment 6 years (2008-2009).

MAPSAR

Phase A Activities (2004-2005)Refinement of the mission requirements and establishment of a function tree of the complete system.

Exploration of alternative system concepts against mission needs.

Investigation of the feasibility of selected orbit with respect to revisit time, stereoscopic and interferometric capabilities.

Investigation of the feasibility of SAR sensor performance and technology evaluation (core radar definition, equipment specification, industrial feasibility).

MMP bus system/subsystems/equipment (MMP performance and configuration, equipment specification, industrial feasibility).

Interfaces between MMP and the SAR payload (systems segments).

Ground system conception and technology.

Airborne simulation campaign (development of MAPSAR user-oriented value added products).

MAPSAR

Proposed MAPSAR Simulation – E-SAR campaign (May 2005)Proposed MAPSAR Simulation – E-SAR campaign (May 2005)

MAPSAR

SIPAM SAR ProgramMAPSAR Simulation Flights: Feb-May 2005

EMB-145 / R-99B

MAPSAR

SAR - Banda L λ= 23,9 cm (1.27 GHz)

SAR - Banda X λ= 3,1 cm (9.68 GHz)

MAPSAR

SIVAM R-99 Mapping Modes

Quad L + Single X

Dual L +

Single X

InSAR +

Single L

Quad L Single L + Single

X

InSAR + Quad L

MAPSAR

Quad L + X (3m) – 10km

Quad L + X (6m) – 20km

Quad L + X (18m) – 60km

Dual L + X (3m) – 20km

Dual L + X (6m) – 40km

Dual L + X (18m) – 120km

Quad L (3m) – 10km

Quad L (6m) – 20km

Quad L (18m) – 60km

L + X (3m) – 20km

L + X (6m) – 40km

L + X (18m) – 120km

SIVAM R-99 SAR: resolution and swaths

MAPSAR

Quad L + X (3m) – 36º - 80º

Quad L + X (6m) – 36º - 80º

Quad L + X (18m) – 45º - 80º

Dual L + X (3m) – 36º - 83º

Dual L + X (6m) – 36º - 83º

Dual L + X (18m) – 45º - 84º

Quad L (3m) – 36º - 83º

Quad L (6m) – 36º - 83º

Quad L (18m) – 36º - 84º

L + X (3m) – 36º - 83º

L + X (6m) – 36º - 83º

L + X (18m) – 45º - 84º

SIVAM SAR R-99: resolution and incidence

MAPSAR

SIVAM SAR Quad-Pol (L-HH)

Serra do Tepequem – Roraima ( spatial resolution = 6m)

MAPSAR

L-VV

SIVAM SAR Quad-Pol (L-VV)

Serra do Tepequem – Roraima ( spatial resolution = 6m)

MAPSAR

L-VH

SIVAM SAR Quad-Pol (L-VH)

Serra do Tepequem – Roraima ( spatial resolution = 6m)

MAPSAR

MAPSAR Simulation (SIPAM SAR Application MAPSAR Simulation (SIPAM SAR Application Program) Program)

GoalsGoals

• to test MAPSAR sensor configuration and establish a to test MAPSAR sensor configuration and establish a proof of concept to meet users need.proof of concept to meet users need.

• to strengthen the capabilities of end-users (“critical to strengthen the capabilities of end-users (“critical mass”) for the effective usage of MAPSAR data for mass”) for the effective usage of MAPSAR data for resource assessment, management and environmental resource assessment, management and environmental monitoring, particularly in the Amazon Region.monitoring, particularly in the Amazon Region.

• to encourage the utilization of new information derived to encourage the utilization of new information derived from MAPSAR (multipolarized L-band images) by relying from MAPSAR (multipolarized L-band images) by relying heavily on Airborne R-99 as a data source for research, heavily on Airborne R-99 as a data source for research, application and training projects.application and training projects.

• to provide demonstration MAPSAR value-added to provide demonstration MAPSAR value-added products for applications (preparing users for the products for applications (preparing users for the advent of MAPSAR). advent of MAPSAR).

MAPSAR

MAPSAR Simulation (SIVAM R-99 campaign)MAPSAR Simulation (SIVAM R-99 campaign)

Proposed strategy :Proposed strategy :

• To simulate MAPSAR far range images (beams7-10) To simulate MAPSAR far range images (beams7-10) with SIVAM A1.Quad L+X near range mode with SIVAM A1.Quad L+X near range mode (incidence: 40 – 48 degrees).(incidence: 40 – 48 degrees).

• Balanced agenda of applications.Balanced agenda of applications.

• Strong participation of INPE and potential end-Strong participation of INPE and potential end-users in the proposals (government, university and users in the proposals (government, university and industry). industry).

MAPSAR

MAPSAR Simulation (SIPAM SAR Application MAPSAR Simulation (SIPAM SAR Application Program)Program)

Test SitesTest Sites: :

• Agriculture: Barreiras (BA) – EMBRAPA, INPE, UnB, UFRJ, Agriculture: Barreiras (BA) – EMBRAPA, INPE, UnB, UFRJ, CPRMCPRM

• Coastal Zone Studies: Bragança (PA) – UFPa, M.P.E. Coastal Zone Studies: Bragança (PA) – UFPa, M.P.E. Goeldi, INPEGoeldi, INPE

• Disaster Management: Terminal Coari/Manaus (AM) – Disaster Management: Terminal Coari/Manaus (AM) – PETROBRASPETROBRAS

• Forestry: Tapajós (PA) – INPE, DSG, DLRForestry: Tapajós (PA) – INPE, DSG, DLR

• Geology: Carajás (PA)/Curaçá (BA) – INPE, Unicamp, Geology: Carajás (PA)/Curaçá (BA) – INPE, Unicamp, CVRD, CPRMCVRD, CPRM

• Hydrology/Forestry: Lago Grande (PA): UVIC (Canadá), Hydrology/Forestry: Lago Grande (PA): UVIC (Canadá), UFPa, INPEUFPa, INPE

• Hydrology/Forestry: Igarapé Açu (AM) – INPE, INPA, JPLHydrology/Forestry: Igarapé Açu (AM) – INPE, INPA, JPL

MAPSAR

News from the last DLR meeting (Nov 2004)

Travelling waves tubes technology may replace solid state high power amplifiers for the radar sensor (space qualified from SAR-LUPE).

a new configuration for the PMM and payload interface will be proposed by INPE taking into account the reflector antenna deployment mechanism.

a demonstrator for the reflector antenna performance is under developement at the Technical University of Munich.

two MAPSAR orbit configurations are under investigation: 7 days repetition cycle for interferometry and 39 days (or 41 days) orbit for stereoscopic applications.

A paper with the current status of MAPSAR project will be presented in Goiânia (BRSS-2005).

MAPSAR

www.obt.inpe.br/satelite/mapsar

MAPSAR

Contents

Motivation

Background

Satellite Concept

Sensor Concept and Performance

Compliance with User Requirements

Current Status