PALSAR is an active microwave sensor using L-band frequency, provides higher performance than the JERS-1's synthetic aperture radar (SAR). It enables to conduct cloud-free and day-and-night land observation. PALSAR has fine resolution in a conventional mode, plus Scan Sar mode that can extract a 250 to 350km width of SAR images at the expense of spatial resolution.
It is utilized to make DEM and to monitor designated area.
Above image is observed by PALSAR on 2006/02/15 (22:16), when ALOS is passing over HIGO waterway from south to north.
The image on the left is a bird's eye view from Mt.Fuji to Izu Peninsula, by using land information data of Geography Survey Institute. Another enlarged image of Mt. Fuji on the right below, topography of Osawanada, western part of the summit, and other parts are clearly appears.
PALSAR is a synthetic aperture radar using microwave, so that it can observe regardless of weather or time of the day. This image is also taken during nighttime observation. Although there had been an occasional rain at that time, PALSAR successfully took a clear image.
PALSAR Major Characteristics
Mode |
Fine Scan |
SAR |
Polarimetric (Experimental mode)*1 |
|
Center Frequency |
1270 MHz(L-band) |
|||
Chirp Bandwidth |
28MHz |
14MHz |
14MHz,28MHz |
14MHz |
Polarization |
HH or VV |
HH+HV or VV+VH |
HH or VV |
HH+HV+VH+VV |
Incident angle |
8 to 60 deg. |
8 to 60 deg. |
18 to 43 deg. |
8 to 30 deg. |
Range Resolution |
7 to 44m |
14 to 88 m |
100m (multi look) |
24 to 89m |
Observation Swath |
40 to 70 km |
40 to 70 km |
250 to 350km |
20 to 65km |
Bit Length |
5 bits |
5 bits |
5 bits |
3 or 5bits |
Data rate |
240Mbps |
240Mbps |
120Mbps,240Mbps |
240Mbps |
NE sigma zero *2 |
< -23dB (Swath Width 70km) < -25dB (Swath Width 60km) |
< -25dB |
< -29dB |
|
S/A *2,*3 |
> 16dB (Swath Width 70km) > 21dB (Swath Width 60km) |
> 21dB |
> 19dB |
|
Radiometric accuracy scene |
1dB / orbit: 1.5 dB |
|||
size of Antenna |
azimuth :8.9m x elevation :3.1m |
Note: PALSAR cannot observe the areas beyond 87.8 deg. north latitude and 75.9 deg. south latitude when the off-nadir angle is 41.5 deg.
*1 Due to power consumption, the operation time will be limited.
*2 Valid for off-nadir angle 34.3 deg. (Fine mode),
34.1 deg. (ScanSAR mode),
21.5 deg. (Polarimetric mode)
*3 S/A level may deteriorate due to engineering changes in PALSAR.