Yong Ge 
  
RESEARCH ABOUT VIRTUAL SAR SYSTEM 
Ge Yong Jinfeng Wang Zhensong Wang Xiaoguang Lou 
1 State Key Laboratory of Resources and Environmental Information System, Institute of Geography, Chinese 
Academy of Sciences, Beijing 100101, PR China, E, mail: gey @lreis.ac.cn; wangjf@lreis.ac.cn; Institute of 
Electron, Chinese Academy of Sciences, Beijing 100080, PR China, E_mail: zswang@ie0.ie.ac.cn; 
yh_lou@263.net 
  
KEY WORDS: SAR, Virtual Reality Technique, Simulation, System 
ABSTRACT: In this paper we propose computer virtual SAR system. This system can produce dynamically SAR 
images not only in various kinds of incident angle wavelength and polarimetric ways of sensor, but also in 
different phases of ground object vegetation variation. Using this system, we can replace field works, save time 
and expenses, and avoid the risk arose by wrong decisions and operations. 
1 INTRODUCTION 
As real-time, high-fidelity visual scene simulation has become ubiquitous in the training, 
modeling and simulation, meanwhile as radar becomes more and more sophisticated and test flights 
more and more expensive, there is an increasing need to simulate the output of different types of 
radar as well as simulate radar performance. 
Next, due to the limitations of equipment and processing techniques, most of operations performed in the air 
during the a series of processes from transmitting wave to producing image will inevitably introduced 
unpredictable system and random error into radar image For example, transfer dissipative aircraft motion error 
and operation error will result in the uncertainty of SAR image. These uncertainty bring difficulties to image 
processing information extraction and the mechanism research of remote sensing( Ge Y, 1999 ). 
So, we propose one kind of virtual SAR system. This system integrates multi-technique which include 
Virtual reality and simulation techniques etc. into one. It can satisfy these needs and solve these problems above 
mentioned. 
In what follows, we first illuminate the characteristics of virtual SAR system. Next, the components of 
Virtual SAR system will be described. Then, How to implement the system will be discussed in section 4 The 
conclusion remarks on virtual SAR system are presented in the final section. 
2 CHARACTERISTICS OF THE VIRTUAL SAR SYSTEM 
The system we have proposed is based on the propagation function of SAR imaging system. It can simulate 
coherent video signal, and operate by interactive transparent way. The user can selects a desired imaging 
radar mode and specifies important mode-dependent radar parameters such as frequency, 
polarization, antenna beamwidth, min/max range extent, min/max scan angle, scan time, Pulse 
Repetition Frequency (PRF) and FFT size. The simulated SAR image is not a simple COPY for the ground 
object or vegetation but the expression of physical mechanism of interesting areas. So we can dig out much more 
knowledge from the image. It can be able to be fused with other remote sensing images. Meanwhile this system 
can be applied to research novel algorithm of imaging process, new imaging system such as strip-map scanSAR 
and spotlight etc. 
3 THE COMPONENTS OF VIRTUAL SAR SYSTEM 
  
124 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B1. Amsterdam 2000. 
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