Long name | PALSAR1 |
Short name | PS1 |
Sensor type | Synthetic-aperture radar (SAR) |
Platform | Advanced Land Observing Satellite-1 (ALOS-1) |
Frequency | 1.2 GHz |
Band (wavelength) | L (22.9 centimeters) |
Polarization | HH, HV, VH, VV (fully polarimetric) |
Key file name (use to open data set) | LED-*, *.meta, *._ortho.dat |
Supported file extensions | LED-*, IMG-*, *.meta, *.SLC.par, *.SLC, *.lea, *.tif, *._ortho.dat, *._ortho.lea |
Data distributor | Japan Aerospace Exploration Agency/Earth Observation Center (JAXA/EOC) |
Sections |
Data product name and description |
Data product name and description
ALOS-1 PALSAR has four acquisition modes, as described in the following table.
Mode | Swath width (km) | Resolution (range x azimuth, m)* | Polarization | Description/notes |
---|---|---|---|---|
High-resolution [H] | 70 | 10.0 x 10.0 (single) |
Single (HH or VV) |
Provides azimuth resolution for two looks. |
Direct downlink [D] | 70 | 20.0 x 10.0 | Single (HH or VV) | Provides azimuth resolution for two looks. |
Polarimetric [P] | 30 | 30.0 x 10.0 | Quad (HH+HV+VH+VV) | Provides azimuth resolution for two looks. |
ScanSAR [W] | 250 (three scans) |
100.0 x 100.0 | Single (HH or VV) | Provides azimuth resolution for eight looks. |
* Resolution is always single-look complex (SLC) unless noted otherwise.
Processing level | Acquisition mode | Description/notes |
---|---|---|
1.0 |
Not supported | Signal data, data type is 8-bit. The number of SAR data files is equal to the number of polarizations in dual-polarization and Polarimetric modes. In ScanSAR mode, data is not separated into individual scans. |
1.1 |
[H] |
Performs range and one-look azimuth compression. On the slant-range coordinate, the data is complex. Phase history is included. |
1.5 |
[H] |
After performing range and multilook azimuth compression, performs radiometric and geometric corrections according to the map projection. Pixel spacing can be selected for Fine mode. Data is detected in amplitude format (16-bit unsigned integer).
Latitudes and longitudes in the product are calculated exclusive of the altitude. Products are available in georeferenced (GR) and geocoded (GC) format. A GR image is oriented in parallel with the direction of the orbit. A GC image is an image projected on a map that is oriented in a map north-south direction. |
1.5 |
[H] single pol | This product is generated from Level 1.1 data acquired in Fine mode with single-polarization and SAR processing applied. It consists of amplitude data sequences spaced equally on ground range.
Products are available in georeferenced (GR) and geocoded (GC) format. A GR image is oriented in parallel with the direction of the orbit. A GC image is an image projected on a map that is oriented in a map north-south direction. SAR georeferenced fine beam (SGF) is derived from the similar RADARSAT-1 product.. SAR systematic geocoded (SSG) is derived from the similar RADARSAT-1 product. The signal data is observed under PALSAR high-resolution in single-polarization mode. |
4.1 |
[H] (dual pol) |
Level 4.1 products are generated from Level 1.0 data acquired in High-resolution mode (dual-polarization) or Polariametric mode.
SAR processing performed on Level 1.0 data includes the following:
Products are available in georeferenced (GR) and geocoded (GC) format. A GR image is oriented in parallel with the direction of the orbit. A GC image is an image projected on a map that is oriented in a map north-south direction. Geocoded products are available in a variety of map projections and pixel spacing. Both are data on ground-range. Additionally, orthorectified Level 4.1 geocoded product is available. An ortho product is made by applying SAR processing, orthorectification, and map projection. A digital elevation model (DEM), such as SRTM, is used for orthorectification. Two formats, GeoTIFF and ERSDAC format (Binary), are prepared for the products. There are two types of ortho products available:
SAR georeferenced polarimetric (SGP): Signal data is observed in PALSAR dual-polarization or quad-polarization mode. Polarimetric systematic geocoded (PSG): Signal data is observed in PALSAR dual-polarization or quad-polarization mode.The SGP and PSG modes are derived from similar Radarsat-1 products. |
4.2 |
[W] | Level 4.2 products are generated from Level 1.0 data acquired in ScanSAR mode (single-polarization).
SAR processing performed on Level 1.0 data includes the following:
Products are available in either georeferenced (GR) or geocoded (GC) format. A GR image is oriented in parallel with the direction of the orbit. A GC image is an image projected on a map that is oriented in a map north-south direction. Geocoded products are available in a variety of map projections and pixel spacing. Both are data on ground range. Additionally, orthorectified Level 4.1 geocoded product is available. An ortho product is made by applying SAR processing, orthorectification, and map projection. A digital elevation model (DEM), such as SRTM, is used for orthorectification. Two formats, GeoTIFF and ERSDAC format (Binary), are prepared for the products. There are two types of ortho products available:
(ScanSAR systematic geocoded (SCG) and ScanSAR (SCN) are derived from similar RADARSAT-1 products. Signal data is observed in PALSAR Wide Area Observing mode. |
JAXA-CEOS (Level 1.1 and Level 1.5)
File name | Format | Required | Contents/details |
---|---|---|---|
LED-* | Product-specific binary | Yes | Key file name. This file is located before the image file. It stores annotation, ancillary, and other types of data related to the image data in the succeeding image file. |
IMG-* | Product-specific binary | Yes | Image data, one image file per polarization. This file is located after the leader file. It stores the image data. |
VOL-* | Product-specific binary | No | Volume descriptor. This file is located at the beginning of the image volume and stores the volume-management and file-management information. |
TRL-* | Product-specific binary | No | This file is located after the image file. It stores the final information related to the image data. |
ERSDAC Vexcel (Level 1.1)
File name | Format | Required | Contents/details |
---|---|---|---|
*.meta | Product-specific binary | Yes | Key file name. Metadata file in XML format. |
*.SLC.par | Product-specific binary | Yes | This file completely describes the characteristics of the floating-point SLC image data file. |
*.SLC | Product-specific binary | Yes | This file contains any of the following:
|
ERSDAC-CEOS (Level 1.5, Level 4.1, and Level 4.2)
File name | Format | Required | Contents/details |
---|---|---|---|
*_XXX.lea | Product-specific binary | Yes | SAR leader file pointer record, where XXX is SGF, SSG, SGP, PSG, SCN, or SCG. |
_XXX.dat | Product-specific binary | Yes | Key file name. Image options file pointer record, where XXX is SGF, SSG, SGP, PSG, SCN, or SCG. |
*_XXX.vol | Product-specific binary | No | Volume descriptor record, where XXX is SGF, SSG, SGP, PSG, SCN, or SCG. |
_XXX.tra | Product-specific binary | No | SAR trailer file pointer record, where XXX is SGF, SSG, SGP, PSG, SCN, or SCG. |
_XXX.nul | Product-specific binary | No | Null volume descriptor record, where XXX is SGF, SSG, SGP, PSG, SCN, or SCG. |
*.meta | Product-specific binary | No | Metadata file in XML format. |
ERSDAC binary ortho products (Level 1.5, Level 4.1, and Level 4.2)
File name | Format | Required | Contents/details |
---|---|---|---|
*._ortho.dat | Product-specific binary | Yes | Key file name. Image options file pointer record contents. |
*._ortho.lea | Product-specific binary | Yes | SAR leader file pointer record. |
*_ortho.vol | Product-specific binary | No | Volume descriptor record contents. |
*._ortho.tra | Product-specific binary | No | SAR trailer file pointer record contents. |
*._ortho.nul | Product-specific binary | No | N/A |
*.meta | Product-specific binary | No | Metadata file in XML format. |
ERSDAC GeoTIFF ortho products (Level 1.5, Level 4.1, and Level 4.2)
File name | Format | Required | Contents/details |
---|---|---|---|
*.meta | Product-specific binary | No | Metadata file in XML format. |
*.tif | Tagged Image File | Yes | Image data. |
*.tif.param | ASCII | N/A | Metadata file in text format |
Returned data for supported format
ALOS-1 PALSAR data can be opened directly in its raw vendor format or imported into a PCIDSK (*.pix) file by using the key file name. For optimal processing, use the PCIDSK format.
The following table describes the data structure after it is imported into a PCIDSK file.
Data product | Data returned | Details |
---|---|---|
JAXA-CEOS Level 1.1 |
1 x [C16S] raster channel (uncalibrated) |
|
JAXA-CEOS Level 1.1 |
2 x [C16S] raster channels (uncalibrated) |
Data can be calibrated in sigma, gamma, or beta nought. |
JAXA-CEOS Level 1.1 |
4 x [C16S] raster channels (uncalibrated) |
Data can be calibrated in sigma, gamma, or beta nought. |
JAXA-CEOS Level 1.5 |
1 x [C16U] raster channel (uncalibrated) |
Data can be calibrated in sigma, gamma, or beta nought. |
JAXA-CEOS Level 1.5 |
2 x [16U] raster channels (uncalibrated) |
Data can be calibrated in sigma, gamma, or beta nought. |
JAXA-CEOS Level 1.5 |
4 x [16U] raster channels (uncalibrated) |
Data can be calibrated in sigma, gamma, or beta nought.
Note: For a fully polarimetric analysis, complex data (Level 1.1) is required.
|
ERSDAC-VEXCEL Level 1.1 |
1 x [C32R] raster channel (calibrated) |
Data is calibrated in beta nought. |
ERSDAC-VEXCEL Level 1.1 |
2 x [C32R] raster channels (calibrated) |
Data is calibrated in beta nought. |
ERSDAC-VEXCEL Level 1.1 |
4 x [C32R] raster channels (calibrated) |
Data is calibrated in beta nought. |
Earth Remote Sensing Data Analysis Center (ERSDAC). ERSDAC PALSAR GeoTIFF Product Format, Version R01. April 14, 2011. Document PG-E-E-0209-R01. 15 pages.
Earth Remote Sensing Data Analysis Center (ERSDAC). ERSDAC PALSAR Ortho Product Formats. Revised R03.0. July 13, 2011. Document PG-E-E-0155-R03.0. 81 pages.
Earth Remote Sensing Data Analysis Center (ERSDAC). ERSDAC PALSAR CEOS Format Specification. Document ERSDAC-VX-CEOS-004. Version date: May 12, 2009, version 1.8. 217 pages.
Japan Space Systems (J-spacesystems). PALSAR Reference Guide. 6th Edition. November 2012. 73 pages.
Japan Space Systems (J-spacesystems). PALSAR User’s Guide. 2nd Edition. November 2012. 69 pages.
Japan Aerospace Exploration Agency (JAXA), Earth Observation Research and Application Center. ALOS Data Users Handbook. Revision C. March 2008. 158 pages.
Japan Aerospace Exploration Agency (JAXA). ALOS/PALSAR Level 1.1/1.5 product format description (English version). Revision L, July 2009. Document NEB-070062B. 158 pages.
Vexel Corporation. Palsar Algorithm Description. August 8, 2003. Document VX-PALSAR-010. 72 pages.
For more information, go to: eorc.jaxa.jp
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