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Phased Array L-band Synthetic Aperture Radar (PALSAR)
The PALSAR is an active microwave sensor aboard the Advance Land Observing Satellite (ALOS). The sensor operates at L-band with HH and VV polarisation (HV and VH polarisations are optional). The sensor is beam steerable in elevation and the ScanSAR mode allows obtaining a wider swath than conventional SARs. ALOS was launched in 2004 into a sun-synchronous orbit at the altitude of 700km, providing a spatial resolution of 20m for the fine resolution mode (swath width of 70km) and 100m for the ScanSAR mode (swath width of 360km). The repeat cycle is 46 days and the local time at descending node is about 10:30am. PALSAR data can be downloaded from ERSDAC. ALOS operations have been terminated on May 12 after a communication shutdown due to a power generation anomaly.
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Source: http://www.alos-restec.jp |
Mission |
PALSAR |
Sensor |
Phased Array L-band Synthetic Aperture Radar (PALSAR) |
Spacecraft |
Advance Land Observing Satellite (ALOS) |
Launch date |
24th, Jan. 2006 |
Design life |
3 - 5 years |
Orbit |
Sun-Synchronous Sub-Recurrent, at an angle of 98.16°, at altitude of 691.65km (at equator). |
Spacecraft operations control centre |
JAXA and JAROS |
Centre frequency (GHz) |
1.27 (L-band) |
Mode |
Fine |
ScanSAR |
Polarimetric (Experimental mode) |
Band width (MHz) |
28 |
14 |
14, 28 |
14 |
Polarisation |
HH or VV |
HH+HV or VV+VH |
HH or VV |
HH+HV+VV+VH |
Incidence angle(°) |
8-60 |
8-60 |
18-43 |
8-30 |
Swath (km) |
40-70 |
40-70 |
250-350 |
20-65 |
Spatial resolution (m) |
7-44 |
14-88 |
100 (multi-look) |
24-89 |
Bit length |
5 bits |
5 bits |
5 bits |
3 or 5 bits |
Radiometric accuracy |
scene: 1dB or orbit: 1.5dB |
Temporal resolution |
Repeat Cycle: 46 days, Sub Cycle: 2 days |
The PALSAR overpass time for the SMAPEx study area is provided in the table below, determined from a Fortran program based on NORAD data, and are provided in the table below. Date and time are in UTC.
●=full PALSAR coverage of airborne box; ○=partial PALSAR coverage
●=concurrent; ●=non concurrent
Date (UTC) |
PALSAR overpass start time (UTC) |
Durations (s) |
Flight Type |
08/09/2011 |
○13:13 |
17 |
No flight
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16/09/2011 |
○0:03 |
17 |
No flight
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