euing 
mplex 
veral 
mplex 
The 
ed by 
data, 
data 
nent, 
it be 
bined 
mplex 
that 
ry to 
nt of 
] the 
utput 
uired 
g the 
tion, 
with 
onger 
t is, 
ions, 
yn in 
11 be 
lifi- 
umber 
x Of 
the 
fects 
o be 
  
Furthermore, the amount of the data input/output to queuing circuits during 
the FFT calculation was reduced to about 1/3.3 as compared with calculation 
performed by real number modules. These reductions point to the use of 
complex number modules as a superior method for the reduction of processing 
time in complex SAR data processing operations. 
The degree to which the SAR data processing time will be reduced depends on 
the number of complex number modules used and the software algorithm. 
6. REFERENCES 
1. J. Gredel; H. Schroter, "Evolution of Digital Ground SAR Processing 
Systems", ISPRS/Comm. II, WG-II/5, Rio De Janeiro, Vol. XXV, Part A2, 
pp.200-pp.209. 1984. 
2. H. Kashihara, et al., "High Speed SAR Data Processing on Data-flow 
Computer NEDIPS", Proc. of the ICASSP 86 Tokyo, Vol. 4 of 4, 
pp.2863-pp.2866, Apr., 1986. 
3, E. O. Brigham, "The Fast Fourier Transform", Prentice Hall Inc. England 
Cliffs, New Jersey, 1974. 
315