ABSTRACT
Synthetic aperture radar (SAR) remote sensing has been extensively used in different thematic applications for geophysical and biophysical parameters retrieval. The active imaging nature of the SAR sensors makes them capable of acquiring data at night-time, while the long wavelength allows them to do imaging in all weather conditions. Due to the enormous scientific applicability of SAR sensors to earth observation as well as planetary applications, several missions have been launched by leading space agencies over the past few decades, and many more SAR missions with advanced capabilities are planned for the future. This chapter provides a brief introduction to the basic concepts of SAR remote sensing. The first section provides information on SAR remote sensing and coherent radar. The second section focuses on the imaging geometry of synthetic aperture radar. The third section of this chapter describes the normalized radar backscatter cross-section estimation from the SAR data, and the fourth section elaborates the local incidence angle estimation using an external digital elevation model (DEM). The fifth section explains the concept of radar polarization used in imaging. The last section explains the different imaging modes of SAR remote sensing.
