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In this chapter we study single scattering. We first consider the case of single scattering by a conglomeration of particles. Then we analyze the SAR technique and examine processing algorithms on the basis that the target background response consists of single scattering. We also study active remote sensing of a random medium based on single scattering. | Scattering of Electromagnetic Waves Theories and Applications Leung Tsang Jin Au Kong Kung-Hau Ding Copyright 2000 John Wiley Sons Inc. ISBNs 0-471-38799-1 Hardback 0-471-22428-6 Electronic Chapter 6 SINGLE SCATTERING AND APPLICATIONS 1 Single Scattering and Particle Position Correlation 232 2 Applications of Single Scattering 237 2.1 Synthetic Aperture Radar 237 2.2 Interferometric SAR 248 2.3 Active Remote Sensing of Half-Space Random Media 252 References and Additional Readings 258 232 6 SINGLE SCATTERING AND APPLICATIONS In this chapter we study single scattering. We first consider the case of single scattering by a conglomeration of particles. Then we analyze the SAR technique and examine processing algorithms on the basis that the target background response consists of single scattering. We also study active remote sensing of a random medium based on single scattering. 1 Single Scattering and Particle Position Correlation Consider a scattering medium consisting of N scatterers centered at ri r2 . rx Fig. 6.1.1 . For the sake of simplicity let each scatterer be a point scatterer with scattering amplitude f. They occupy the region between z 0 and z d. Let the incident wave be e 7 6.1.1 where ki k sin 0i cos fax k sin 0 sin fay k cos dzz 6.1.2a I- kiyy kizz 6.1.2b Then under single scattering the scattered field from particle j centered at rj is pifclr-rjl _ T---------eiki ri Thus the total scattered field is W ifclr-Fjl _ V r -elki ri J 1 1 J In the far-field observation direction of ks where fcs kka k sin 0S cos fax k sin 6S sin fay k cos 0sz ksxx ksyy kszz 6.1.3 6.1.4 6.1.5 the scattered field is given by ikr N _ _ _ fa ks fci E e k 6.1.6 where denotes scattering from direction ki to direction ks. First we calculate the coherent scattered field ÿs . From 6.1.6 we obtain ilçT _ fa fe ki-k 6.1.7 j l 233 1 Single Scattering and Particle Position Correlation Figure 6.1.1 Scattering by a slab consisting of N point scatterers. Let the cross-sectional area of the .