MIRAS Demonstrator Pilot Project #3 (MDPP-3) SMOS SAG Meeting No. 20 2-3 November 2006Slide 1 ESAC - Villafranca del Castillo Airborne MIRAS Description

MIRAS Demonstrator Pilot Project #3 (MDPP-3)

SMOS SAG Meeting No. 20 2-3 November 2006 Slide 1ESAC - Villafranca del Castillo

Airborne MIRAS Airborne MIRAS Description & Tests ResultsDescription & Tests Results



• Project Frame and Objectives

• Project Team

• Activities Summary

• Demonstrator Description

• Tests Campaign Description

• Tests Results

• Project Achievements

ContentsContents



ESA Programme: Validation of L-Band Radiometry

ESA Contract: 15138/01/NL/SF

Project Designation: MIRAS Demonstrator Pilot Project #3

• Airborne Demonstrator (AD – MDPP3)

• Image Validation Test (IVT – MDPP3)

Project Duration: 32 months (Feb-2004 / Oct-2006)

Project Frame



MAIN OBJECTIVES:

• To build an Airborne MIRAS demonstrator by using the MDPP-1 and 2 hardware

• To carry out a flight demonstration of the above instrument to extend the imaging validation to real targets

• To assess the capability of calibrating the Instrument through Cold Sky measurements

OTHER OBJECTIVES:

• To complete the analysis of the MDPP-2 and the IVT-4 campaigns test results

• To test the double-amplitude noise injection for amplitude calibration

• To experimentally demonstrate the way of obtaining the FwF through different methods, and

• To validate methods for the assessment of residual correlations

Project Objectives



Prime Contractor

Airborne Demonstrator Design, Manufacturing and AIT

Aircraft Interface Design and Manufacturing

Flight Demonstration

Residual Correlation and calibration

EGSE Design and Manufacturing

Mission Plan

Collaboration in tests results processing

Demonstrator Characterisation and Performances Tests

MDPP-3 Tests results processing

MDPP-2 Data Processing / Theoretical Support

IVT-4 Data Process

Contribution to Antenna Functional Tests

Modifications on LICEFs, NIR & Clock Generator Development

Modifications on DICOS-2

Project Team



Activities SummaryActivities Summary



AMIRAS Development

MDPP-1 & 2 Equipments

MIRAS Instrument

Concept

Airborne MIRAS Design

AircraftConstraints



AMIRAS Architecture

Antenna &

Equipment Controllers

EGSE

Antenna Controller

POWER

COMMANDS & DATA

TRANSFER

Instrument Structure

Aircraft Structural Interface

Aircraft Electrical Interface

POWER

Thermal

Control

POWER



AMIRAS Development

MDPP-1 & 2 Equipments

MIRAS Instrument

Concept

MDPP-n Equipment Selection

MDPP-n Equipment Modification

New Equipment Acquisition

Airborne MIRAS Design

Antenna Devlmt:StructureThermal ControlHarness

Aircraft/Antenna Interface

Development

AircraftConstraints

Antenna Controller (EGSE) Development

Airborne MIRAS

Assembly Integration Verification



AMIRAS Test Campaign

Airborne MIRAS

Antennae Characterisation

Demonstrator Performances

Image Validation Tests / Cold Sky Measurements

Image Validation Tests / Flight Demo

onto real targets

Experimental Validation of several

MIRAS Instrument Capabilities

Availability of an Airborne MIRAS

Instrument:

AMIRAS

Progress on MIRAS Instrument Data

Process Algorithms



Project Shedule



Demonstrator DescriptionDemonstrator Description



Antenna Lay-out • 12 element antenna array• Y-shaped• NIR antenna placed at the centre• Element interspacing: d = 0.875



Demonstrator Equipment

CAS-NS

CAS-PD



Ground Plane - connecting all the antennas



The Aircraft Interface Structure



Antenna Radome



Airborne Antenna

Controller Unit (EGSE)



Tests at UPC Anechoic Chamber:

Antenna Pattern and Performances



Tests at IRTA: Cold Sky (Calibration) and Sun/Galaxy

(Imaging)



The HUT Aircraft: SHORT SC-7 SKYVAN



AMIRAS Installed in TKK Aircraft

Antenna

Controller Unit (EGSE)



Ready for Flight Tests Campaign



Test Campaign Test Campaign Description & ResultsDescription & Results



Antenna Characterisation Tests:

• Measure the antennae Radiation Patterns

Demonstrator Performances Tests: • Basic Operation

• Empty Chamber

• Point Source

• Fringe Washing

Image Validation Tests at IRTA:• Galaxy Detection

• Assessment on instrument calibration through Cold Sky measurements

Flight Tests in Finland: • Assessment of EMC between Aircraft and AMIRAS

• Demonstrate functionality of AMIRAS when in-flight conditions

• Perform Measurements onto Real targets (Sea water, bare soil, vegetation,…)

• Repeat Cold Sky Measurement to assess instrument calibration

Test Campaign Objectives



Antenna Characterisation Test

UPC anechoic chamber



Antenna Characterisation Test

• Far-field patterns (Eθ,E) computed using spherical mode expansion from Near-field data.

• Patterns referred to the center of rotation of the spherical system.• Post-processing:

– Translation to nominal positions in the arms. – Conversion to copolar and crosspolar components (Ludwig 3rd).– Coordinate conversion to director cosines (ξ,η).– Normalization with respect maximum value.– Directivity and solid angle computation.

• Interactive viewer – antenna patterns\index.htm



…..

Copolar pattern Aperture fields

Phase (copolar)Amplitude

Co-polar

Cross-polar η=0

ξ=0



Empty chamber:

Noise source off

Instrument facing a chamber wall

Point source:

Noise source on

Instrument as in the picture

Horn rotated at 0º, 45º and 90º

Demonstrator Performances Tests

α<0

β<0

γ<0

Anechoic chamber door

A

BC

Radiated Electric field

α<0

β<0

γ<0

Anechoic chamber door

A

BC

Radiated Electric field

ERA-3 ERA-3

50 Ω 0-50 dB~20 dB~20 dB

Horn

D=12 dB

Tph



Polarization switch consistency

-5000 0 5000

-6000

-4000

-2000

0

2000

4000

6000

e[Mkj](c.u.)

m

[Mkj](

c.u

.)

V-pol, =0º, =-90º, =-90º

Horn Vertical

Horn Horizontal

V-pol

-5000 0 5000

-6000

-4000

-2000

0

2000

4000

6000

e[Mkj](c.u.)

m

[Mkj](

c.u

.)

NIR-H mixed baselines

NIR-V mixed baselines

V-pol, =0º, =-90º,=0º

-5000 0 5000

-6000

-4000

-2000

0

2000

4000

6000

e[Mkj](c.u.)

m

[Mkj](

c.u

.)

H-pol, =0º, =-90º, =-90º

NIR-V mixed baselines

NIR-H mixed baselines

H-pol

-5000 0 5000

-6000

-4000

-2000

0

2000

4000

6000

e[Mkj](c.u.)

m

[Mkj](

c.u

.)

H-pol, =0º, =-90º,=0º



Empty Chamber Correlation Offsets

0 10 20 30 400

20

40

baseline number

c.u

.

ECCOS H-pol. nominal

50 60 70 80 900

20

40

baseline number

c.u

.

-40 -20 0 20 40

-40

-30

-20

-10

0

10

20

30

40

e[Mkj](c.u.)

m

[Mkj](

c.u

.)

ECCOS H-pol. nominal

0 10 20 30 400

20

40

baseline number

c.u

.

ECCOS V-pol. nominal

50 60 70 80 900

20

40

baseline number

c.u

.

-40 -20 0 20 40

-40

-30

-20

-10

0

10

20

30

40

e[Mkj](c.u.)

m

[Mkj](

c.u

.)

ECCOS V-pol. nominal

V-pol

H-polA1-A2

A2-A3

A3-A4



Point Source Test Results

-1000 0 1000 2000-1500

-1000

-500

0

500

1000

1500

e[V](K)

m

[V](

K)

Point source Visibility 07-Apr-2006 09:21:39

Measured at receiver input

Computed at antenna plane

chrrjk

jkjk

jk

chskj Veccrr

TTV jk

)(*

2

4)(

Translated to antenna plane

Fully Calibrated Visiblility



IRTA (Institut de Recerca i Tecnologia Agroalimentària)

Ebro River Delta. Catalonia

Image Validation Tests



Sun tracking during day

Cold Sky calibration during night

Galaxy imaging when present in FOV

Instrument installation at IRTA

GPS antenna

Metallic fence



Flat Target Response

0 5 10 15 20 25 300

50

100

150

baseline number

[x 1

e-4

]

Flat Target Response. V-pol, nominal correlation

A1-A2 A2-A3

A2-A4

A3-A4

A2-C2 A3-C4

35 40 45 50 55 60 650

50

100

150

baseline number

[x 1

e-4

]

B1-B2

A4-C4

B2-B3 B3-B4C1-C2

C2-C3

0 5 10 15 20 25 300

50

100

150

baseline number

[x 1

e-4

]

Flat Target Response. H-pol, nominal correlation

A1-A2A2-A3

A3-A4A3-C4

35 40 45 50 55 60 650

50

100

150

baseline number

[x 1

e-4

]

B1-B2 B2-B3

B3-B4

B2-C4 B3-C4

C1-C2

C2-C3C3-C4

0 5 10 15 20 25 300

50

100

150

baseline number

[x 1

e-4

]

Flat Target Response from antenna patterns. H-pol

A1-A2 A3-A4

A1-C1

35 40 45 50 55 60 650

50

100

150

baseline number

[x 1

e-4

] B2-B3B3-B4

C1-C2

C1-C3

C2-C3

C3-C4B1-B2

B1-B3

0 5 10 15 20 25 300

50

100

150

baseline number

[x 1

e-4

]

Flat Target Response from antenna patterns. V-pol

A1-A2

A2-A3 A3-A4

35 40 45 50 55 60 650

50

100

150

baseline number

[x 1

e-4

]B1-B2

B2-B3

B3-B4 C1-C2 C3-C4

Cold Sky measurement

Theory

V-polH-pol



NIR calibration

0 20 40 60 80480

490

500

510

520

530

540

550

Time from start (min)

K

NIR Internal noise source (TNA)

NIR-HNIR-V

0 20 40 60 803500

4000

4500

5000

5500

6000

6500

7000NIR Internal noise source (TNR)

K

Time from start (min)

NIR-HNIR-V



Sun and Galaxy images



Flight Test

• Flight altitude: ~ 400m over land and lakes and 600m over open sea.

• Aircraft velocity: ~60m/s• Pitch: ~4º (nose up)• Integration time: 200ms to reduce

blurring.

Flight dates:20th June 2006 (night)19th July 2006 (night)20th July 2006 (day)21th July 2006 (day)



First and second flights

Calibration is performed at the beginning and end of flight legs

19th July 2006 20:07 to 22:32 UTC20th June 2006 20:00 to 21:39 UTC

Cal

Cal

Ca

l

Cal Cal

Cal

Cal

Cal

CalCal



Ferry flight to Lathi:

20th July 2006 16:21 to 16:51 UTC

Ferry flight back to Helsinky:

21th July 2006 10:05 to 10:39 UTC

Third and fourth flights and cold sky measurement

Cal

Cal



Results from the first flight: Pensaari island



Single Snapshot over fresh water (τ=200 ms)

Horizontal Vertical• Residual systematic errors are still present. Probably due to:

- Receiver B1 is failing- Mixed baselines are corrupted and not used.- Inversion algorithm is FFT with average antenna pattern.- Fringe-washing function is not taken into account.- Some external interferences from aircraft were observed



Incidence angle dependence

KNB

Td vw

eff

sysT 36.1

2

3 2

KT 43

Amplitude calibration error

Aliasing effect

Theoretical radiometric sensitivity due to limited integration time

• NIR was not available for absolute calibration.

• An estimation from PMS was used instead.



MDPP-3 Project AchievementsMDPP-3 Project Achievements



Main achievements of the project have been:

a) Delivery of a Y-shaped MIRAS airborne demonstrator, fully polarimetric

b) Polarimetric formulation of the Corbella equation

c) First galaxy image ever with a Y-shape MIRAS demonstrator (IRTA)

d) Flat Target Transformation experimental validation (IRTA)

e) Demonstration of imaging capabilities in airborne conditions

f) First experimental verification ever of the FwF closure (using HUT-2D)

g) Consolidation of calibration, data processing and image reconstruction for SMOS

AMIRAS Availability:

• The airborne demonstrator is currently stored at TKK (HUT) premises in Helsinki

• Future Test Campaign should take account that receiver B1 functionality must be checked and repaired if needed

Documents

MIRAS Demonstrator Pilot Project #3 (MDPP-3) SMOS SAG Meeting No. 20 2-3 November 2006Slide 1 ESAC - Villafranca del Castillo Airborne MIRAS Description