tropiscat : a multi-frequency polinsar data campaign of acquisition for vegetation characterization...
Post on 14-Dec-2015
213 Views
Preview:
TRANSCRIPT
TropiSCAT : A MULTI-FREQUENCY POLINSAR DATA CAMPAIGN OF ACQUISITION FOR
VEGETATION CHARACTERIZATION
Clément ALBINET – Office National d’Etudes et de Recherches Aérospatiales (ONERA)
Pierre BORDERIES – Office National d’Etudes et de Recherches Aérospatiales (ONERA)Thierry KOLECK – Centre National d’Etudes Spatiales (CNES)
Fabio ROCCA – Politecnico di Milano (POLIMI)Stefano TEBALDINI – Politecnico di Milano (POLIMI)
Thuy LE TOAN – Centre d’Etudes Spatiales de la BIOsphère (CESBIO)Ludovic VILLARD – Centre d’Etudes Spatiales de la BIOsphère (CESBIO)
Stéphane MERMOZ – Centre d’Etudes Spatiales de la BIOsphère (CESBIO)Dinh HO TONG MINH – Politecnico di Milano (POLIMI)
IGARSS 2011 VANCOUVER – Friday, July 29 – FR3.T02 The BIOMASS Mission
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
• BIOMASS Mission, candidate for the ESA 7th Earth Explorer Mission
• First Synthetic Aperture Radar (SAR) at P-band
3
Motivation and objectives
• Forest with high biomass density (>300ton/ha) → PolInSAR
High temporal coherence is necessary !
→ Airborne experiment : TropiSAR (2009)
→ Ground based experiment : TropiSCAT
(ESA and CNES founding)
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
4
1. Experiment description
• Goal :• Polarimetric intensity• Polarimetric complex coherence• Polarimetric vertical imaging (tomography)
• Time scales :• Minutes• Daily• Monthly• Yearly
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
5
1. Experiment description
• Equipment :
• VNA – Agilent A5061B :• With IF=1kHz, noise is less than -100 dBm.
• Antennas – SATIMO LP400 :• 400MHz – 1GHz• Adequate 3dB aperture : E - 50° / H - 65°.
• RF Switches :• Solid state switches.
• 70m Low loss cables :• Losses measured in laboratory range from
3 dB at 400 MHz to 5 dB at 1 GHz.
• Industrial Computer :• Compact design• Tropicalized motherboard• Waterproof
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
• Location - Requirements :• High biomass density• High number of different tree species• High spot for radar measurement• Safe place for hardware
→ Guyaflux tower in Paracou, French Guiana
6
1. Experiment description
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
• Location : 55 m high Guyaflux tower in
Paracou, French Guiana
7
1. Experiment description
Primary forest
Continuously studied since the seventies Ground data are continuously collected
(weather, soil moisture, tree measurements)
Test site overflown by TropiSAR campaign (ONERA, August 2009)
view from the top of the tower :
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
8
2. Instrument architecture
• Project evolution/planning :• October 2010 – Preliminary campaign with light equipment.• June 2011 – Setup of the automatic full-polarimetric backscattering and
coherence measurements.• September 2011 - Setup of the automatic tomographic measurements.
• Instrument architecture :• 4 antennas configuration
RF Transmit
RF Receive
RF switches box
Vector Network Analyzer
Control Unit
Control and Monitoring PC
Eth
ern
et lin
k
US
B lin
k
Guyaflux tower
Internet Gateway(if available)
Antennas
Power line (24V)
Control line
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
9
2. Instrument architecture
85cm
70cm
70cm
150cm
T-V T-H R-H R-V
Tower
Forest
• 4 antennas configuration :
Full polarization impulse responses
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
10
3. TropiSCAT first results
• Extremely high coherence on tower
• Range gate on the tower at P band :
Validation of coherence measurements
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
11
3. TropiSCAT first results
• Diurnal cycle & High coherence for one day interval• Strong decorrelation during storm, stronger for foliage only• Stronger decorrelation for full forest
High influence of soilProminent influence of soil moisture variation ?
Further analysis necessary with ground data
• Range gate on the forest at P Band :
24 hours
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
12
3. TropiSCAT first results
• Foliage only at 2 bands :
• Stronger decorrelation at L band
• Stronger decorrelation on HH at L band
P band L band
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
13
3. TropiSCAT first results
• Full forest at 2 bands :
• For HV : day night same order of decorrelation.
• Stronger decorrelation on VV at L band during the whole day, including same hour.• Stronger decorrelation at L band for HH.
P band L band
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
14
3. TropiSCAT first results
• HH
• HV
• VV
• Vertical tomography :
Localization of the contributors
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
15
3. TropiSCAT first results
Validation of tomograms
• Vertical tomography :
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
16
4. TropiSCAT development
• Project evolution/planning :• October 2010 – Preliminary campaign with light equipment.• June 2011 – Setup of the automatic full-polarimetric backscattering and
coherence measurements.• September 2011 - Setup of the automatic tomographic measurements.
• Instrument architecture :• Antenna array configuration : 20 antennas
RF Transmit
RF Receive
RF switches box
Vector Network Analyzer
Control Unit
Control and Monitoring PC
Eth
ern
et lin
k
US
B link
Guyaflux tower
Internet Gateway(if available)
Antennas
Power line (24V)
Control line
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
• The TropiSCAT experiment has been partially installed in French Guiana and is currently running
• The first measurements show that TropiSCAT experiment can achieve the scientific objectives
• The first results yield physical interpretation
17
Conclusion
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
18
TropiSCAT : A MULTI-FREQUENCY POLINSAR DATA CAMPAIGN OF ACQUISITION FOR VEGETATION CHARACTERIZATION
Thank you for your attention.
(360° panorama from the top of the tower)
Clement.Albinet@onera.fr
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
19
Modeling
• Comparisons between measurements and modeling : Interpret the temporal variations observed in the long term experiment.
• Situation of the plot :• West side of tower• Surface of 172 m²
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
20
Modeling
• Comparisons between measurements and modeling : Comparisons with measurements from the TropiSAR airborne campaign
IGA
RS
S 2
011
VA
NC
OU
VE
R –
Fri
day,
Ju
ly 2
9 –
FR
3.T
02
Th
e B
IOM
AS
S M
issi
on
Deforestation
Regeneration
21
Introduction and Context
Carbon fluxes and its uncertainties [BIOMASS 08]
Biomass changes on tropical forests
P-band (435MHz) now available
Carbon Budget
top related