SAR 
IOCS antenna 
    
    
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
rack 
ence 
slice BB ms van ot vq 
| its * 
] low m 
\R, is =. AVNIR-2 
ailed 
etry. 
patial 
m of Figure 1. ALOS spacecraft in-orbit configuration 
ering 
guity 
al to Table 2. PALSAR basic characteristics 
rage 
] the Low data rate Cómbari 
; ; ; parison 
SAR Observation mode Fine resolution ScanSAR ; | - Note JERS-1/SAR 
0 dB 
i Center freq. L-band 
data Frequency band -TB.D. centered at1275MHz 
bits 
A Selectable by 
C) of Polarization HH or VV commands HH 
its of 
18-36deg.(3 scans) Look angle 37-42deg. 
Incidence angle 20-55deg. 18-40deg.(4 scans) | 20-55deg. 20-55deg. range (fixed) 
18-43deg.(5 scans) 18-48 deg. Look angle:35 deg. 
ation 
YW US Range 10m* 100*m 10m* 20m* 18m 
(s by Spatial * at look-angle 
imes resolution of 35 deg. 
: ; 10m(2looks 10m(2looks) | 10m(2looks) 
Azimuth | „Om(4looks) 100m 20m(4looks) | 20m(4looks) 18m (3 160k8) 
lages 
and 
: 250km(3 scans) *-BEIOGK | 
it, by Swath 70km* 300km(4 scans) 50km* 50km* a à eS cand e 75km 
t the 350km(5 scans) 9 
” Bit length 5bits | + Sbits Q 3bits | + 3bits Q 3bits | + 3bits Q 
in be Data rate 240Mbps 120Mbps 120Mbps 60Mbps 60 Mbps 
ig X- 
1e X- Radiometric accuracy 1dB 
n this N | look-angl 
; oise equivalent -25dB* * at look-angle -20.5dB 
oatial backscattering coefficient of 35 deg. 
wath , 
it the S/A 25dB* = ange 14 dB 
en in 
st as Mass 440kg 228kg 
Power consumption 1100W 500W 
  
  
  
  
  
  
4.2 PALSAR Hardware Configuration phased-array antenna, light weight T/R modules are 
necessary and being developed. The antenna elevation 
angle is mechanically set to 48 degrees of off-nadir angle 
and can be steered more than 30 degrees to the nadir by 
controlling five bits phase-shifter in each T/R module. 
An elevation beam steering, which is used for look angle 
change in the fine resolution mode or the ScanSAR mode, 
is achieved by employing the active phased array 
technique to the PALSAR. In order to implement an active 
195 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B1. Vienna 1996