Alaska Satellite Facility - Distributed Active Archive Center


ALOS Phased Array type L-band Synthetic Aperture Radar


From 2006 to 2011, PALSAR’s L-band synthetic aperture radar (SAR) yielded detailed, all-weather, day-and-night observation, as well as repeat-pass interferometry. PALSAR data are from multiple observation modes with variable polarization, resolution, swath width, and off-nadir angle.

PALSAR was one of three instruments on the Advanced Land Observing Satellite (ALOS), also known as DAICHI, developed to contribute to the fields of mapping, precise regional land-coverage observation, disaster monitoring, and resource surveying. ALOS was a mission of the Japan Aerospace Exploration Agency (JAXA).


Product Type Format Open Access
L1.0 Unprocessed/raw n/a Find Data
L1.5 Georeferenced amplitude image CEOS Find Data
RTC Radiometrically and terrain-corrected geocoded GeoTIFF image GeoTIFF Find Data

Note 1: L1.0 and L1.5 products may have originated from older JAXA processor versions.

Note 2: Users may request L1.1 data – if not already available through Vertex or the ASF API – by contacting our User Support Office, [email protected]. Please provide a list of the granule names you wish to have processed.
L1.1 processing is not possible for data acquired in ScanSAR beam mode (WB1 and WB2).

How to Obtain PALSAR Data

Researchers can download open-access ALOS PALSAR data from the NASA-sponsored ASF DAAC.

PALSAR Technical Specs — Beam Modes

PALSAR has two fine beam modes: single polarization (FBS) and dual polarization (FBD), as well as quad polarization, also known as polarimetric mode (PLR). ScanSAR wide beam (WB1, WB2) operates with a considerable loss of resolution. See table below.

Fine Resolution ScanSAR Polarimetric
Center Frequency L-Band (1.27 GHz)
Polarization HH or VV HH+HV or VV+VH HH or VV HH+HV+VV+VH
Spatial Resolution 10 m 20 m 100 m 30 m
Swath Width 70 km 70 km 250-350 km 30 km
Off-Nadir Angle 34.3° (default) 27.1° (default) 21.5° (default)

PALSAR cannot observe the areas beyond 87.8 degrees north latitude and 75.9 degrees south latitude when the off-nadir angle is 41.5 degrees.

Read more on the JAXA website.