Distance - Doppler Algorithm-based Fm Continuous Wave Sar Imaging Studies

Frequency Modulation Continuous Wave Synthetic Aperture Radar (FMCW SAR) combines CW radar technique and SAR technique.It could get radar imaging of high resolution.And it has many advantages such as simple structure, small size, light weight, low cost.All of these make it has more and more applications in the field of radar imaging.In FMCW SAR, the system sends continuous signal and the signal's lasting time occupies the entire cycle,which makes the echo model and the imaging process different from that of pulse SAR. Therefore, analyzing the characteristics in the pulse SAR system and FMCW SAR system and researching on the imaging process that is suitable for FMCW SAR system is of great significance.At first, the basic principle of the SAR is introduced. Also,the principle of getting high resolution in range using the pulse compression technology and the principle of getting high resolution in azimuth using SAR technology are analysed.On this basis the theoretical model of the SAR is studied.Then the echo model and imaging process of one point in the pulse SAR system and FMCW SAR system are studied.On the basis of analysing the basic imaging arithmetic in thepulse SAR------Range-Doppler (R-D) arithmetic, the improving R-D arithmetic that issuitable for FMCW SAR is studied. Finally the emulational results in the pulse SAR and FMCW SAR is given,using R-D arithmetic on the side-look.At last, the selectional request of the parameters such as the sampling frequency in FMCW is discussed,and the differences between FMCW SAR and pulse SAR in the signal model and the imaging process are analysed and summarized.