CALVAL PALSAR

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CALVAL - PALSAR Masanobu Shimada ALOS research
Program Manager Earth Observation Research and
application Center(EORC) Japan Aerospace
Exploration Agency (JAXA) shimada.masanobu_at_jaxa.jp
CEOS 22th CAL/VAL plenary _at_ USGS Sioux Falls,
SD, USA
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Two failures in 2003 made delays of restarting
JAXA space programs. Launcher failure error
analysis and resolving plan were approved by
Japan space committee. -gt small hole of boosters
nozzle burned the ignition line for
separation. Satellite failure of ADEOSII Error
analysis is being conducted. Estimated cause is
short circuit of the power lines which collect
electricity generated by the solar paddle, due to
accumulated degradation of the line material by
arching and high temperature.
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• CALIBRATION-status (2003 May 2004)
• CAL Meeting at EORC (Sept 16-17 2003)
• Collects the calibration sites world widely.
  Participants, ALOS PIs and Node delegations(ASF),
  discussed setting up the available calibration
  sites from the Initial CAL phase, and
  availability of the data.
• Calibration algorithm development
• Image quality evaluation function
• Absolute calibration coefficientsUse CR and
  ARCs.
• Antenna pattern estimators, using Amazon rain
  forest.
• Polarimetric Calibration AlgorithmUse forest
  data, Corner reflectors, Active radar
  calibrators.
• Verification Experiments Use Pi-SAR data
  acquired over Tomakomai calibration sites
  (2002-2004).
• Software(SIGMA-SAR) upgrade
• Add functions to Image quality evaluations.
• SCANSAR update (Chirp-z and FFT)
• Calibration procedure evaluated (using Pi-SAR)
  and implemented.

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Evaluation of the on-ground test data Chirp
replica -gt well collected. The other
data(End-to-end test) under evaluation.
Azimuth pattern of raw data
Range Correlation
I (HH,HV) wave
Power spectrum
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Process flow
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16 bits
L1.0 data(raw data)
Telemetry analysis and correction
?
Doppler/Doppler rate analysis
POLCAL distortion correction multilook16 bits
Range compress(Chirp rate correction)
range, antenna correction
Range migration
SCANSAR
STRIP
Specan
Azimuth compression(SRC)
Multi look
Multilook
?
?
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Pi-SAR
Frequency 1.275e9 Hz Band width 50 MHz Sampling
freq. 61.275MHz Height 612Km Image
swath lt15Km AD(I/Q) 8 bits r (R) slant 3 m r
(A) 4look 3.2 m s0 1.1 dB NEs0 -30 dB Inci.
Angle 1060 Polarimetry Full t 10ms Pt 3.5KW Bea
m width(A) 8.4 degrees
Tottori Dune
N
Sigma-SAR processor
RHH,GHV,BVV
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Polarimetric calibration procedureImplemented in
next version.
Uncalibrated SLC(UC1.1) and calibrated SLC(C1.1)
are related by
UC1.1
C1.1
Dr
Dt
Distortion matrices, Dr, Dt, depend on incidence
angle (q) and time(t).
Incidence angle dependence of f1, f2,from pi-SAR
calibration study.
Other than Van Zyl and Quegan algorithms, JAXA
developed a distributed target based algorithm to
determine distortion matrices. The advantages
enables incidence angle dependency. These
matrices (parameters) will be determined several
times and evaluated in calibration phase. The
parameters will be distributed to NODE for data
compatibility with JAXA.
Dr and Dt12 scalar parameters (Example)
1.138679e00 -2.106416e-01 0.000000e00 -7.241599e
-02 2.510327e-03 0.000000e00 1.346348e00
-2.288985e-01 0.000000e00 4.468928e-01
-2.510345e-03 0.000000e00 -4.602865e-02
7.598560e-02 0.000000e00 1.314591e00
6.782417e-01 0.000000e00 3.175881e-02
-3.824020e-03 0.000000e00 1.822099e00
3.960583e-01 0.000000e00 5.389908e-02
-3.755815e-02 0.000000e00 3.381263e00
-1.072618e00 0.000000e00 -2.499185e-02
8.343484e-02 0.000000e00 -7.667590e-01
-8.327003e-01 0.000000e00
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3.0m Corner reflector_at_Tomakomai forest. adjusted
for Ascending PALSAR beam 7. RCS38 dBsm, and
signal to clutter ratio gt28 dB.
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Temporal Change of the Calibration factors
Six years variation of the calibration factors,
PI-SAR
UnitDecibel Refer to the paper M. Shimada, et
al.,Determination of Polarimetric calibration
parameters of L band SAR using uniform forest
data ,IGARSS2004, Anchorage, USA
SIGMA-SAR
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Calibrated data
Uncalibrated
Polarimetric signatures of calibrated and
un-calibrated SIGMA-SAR data
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Comparison of the before and after calibration
(Forest case)
Phase residual error
Amplitude -gt Slightly corrected. Phase -gt
significantly corrected (lt2deg.).
Pi-sar images over tomakomai forest region
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Institute Type Numbers Locations JAXA PARC 1 Hatoy
ama CR 2 Tomakomai/Kanto CAL PIs CR TBD CCRS(UKD
LR) CRPARC 6 JAPAN CRANT 24 RUSSIA CR 5 JPL
ASF/NOAA CR 10 ALASKA JAXA Forest 1 Amazon JAXA Ic
e 2 Greenland/Antarctica
PALSAR Calibration sites
Distributed target (Antenna)
Determined sites
Being determined
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Project Schedule
Launch
3mos
5mon
L9
Data release
Data release(limited for PI , PDF for general)
CAL/VAL review march 20 2003
CAL/VAL review DEC 2003
EOC software version
Ver.0
Ver.1
Ver.2
Ver.n
CAL/VAL meetings
EORC software version
PI meeting (Jan. 2004)
Ver.0
Ver.1
Ver.n
1 year after
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Pi-SAR REPEAT PASS InSAR
SIGMA-SAR
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ALOS Satellite System
Data Relay Antenna
Star Tracker

GPS Antenna
PALSAR
PRISM
AVNIR-2
Solar Array Paddle
Velocity
Nadir
PRISM Panchromatic Remote-sensing Instrument
for Stereo Mapping AVNIR-2 Advanced Visible and
Near Infrared Radiometer type 2 PALSAR Phased
Array type L-band Synthetic Aperture Radar
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• Summary
• POLCAL procedure has been evaluated and validated
  using Pi-SAR data and implemented in SIGMA-SAR.
• Calibration procedure has been also evaluated and
  validated using Pi-SAR data and implemented in
  the SIGMA-SAR.
• E-to-E and compatibility data will be analyzed in
  next phase.