VI CONCLUSION 
This paper reports some features of the Danish KRAS radars design. The system is a C-band 
high resolution airborne SAR. The top level system parameters and system block-diagram 
are presented. Two subjects of main concern in the design is maximum flexibility and system 
calibration. The flexibility has been achieved by applying digital technology to the largest 
possible degree. The transmitted pulses are coded in a digital signal generator that can 
generate any pulse modulation up to a maximal length of 20 us. It is presently being studied 
how predistortion of the pulses can be used to compensate for different system errors. The 
calibration efforts have led to the inclusion of radiometer design techniques such as 
temperature stabilization and internal calibration loops. Other calibration tasks includes 
precision measurements on the antenna and comparison with a scatterometer system. The 
first test flights are expected in the summer 1989. 
ACKNOWLEDGEMENTS 
The KRAS research programme is supported financially by the Thomas B.Thriges 
Foundation. Without that support the project would not have been. 
The authors would especially like to thank their colleagues À. Netterstrgm, K. Woelders and 
A. Ostergaard for their contributions to the radar design. 
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