Radar is an active microwave remote sensing system, first developed during the Second World War with the purpose of evaluating distances between targets (aircrafts, ships, etc.) and the antenna used to send and receive an Electromagnetic (EM) pulse (Woodhouse 2006; Brown 1999). After the war, the technique stopped being exploited exclusively for aircrafts/ships ranging and found interesting applications in remote sensing of the environment as well. Since its introduction in the remote sensing scientific community, radar has experienced a rapid growth, with the proliferation of numerous applications/techniques exploiting different features of the coherent acquisition of microwaves (Woodhouse 2006).