Real aperture radar system for use on board a satellite and for maritime surveillance applications

摘要

The present invention regards a method of operation of a real aperture radar system (30) for surveillance of the Earth's surface, said real aperture radar system (30) being installed on a space vehicle/platform (20) that moves in a direction of flight and comprising a transceiving antenna (32), or a transmitting antenna and a receiving antenna, which is/are electronically steerable. The method comprises: a) transmitting, via the transceiving/transmitting antenna (32), a series of M radar pulses towards a swath of the Earth's surface parallel to the direction of flight using an antenna beam pointed at said swath, wherein M is an integer greater than two; b) for each of the M radar pulses transmitted, receiving, via the transceiving/receiving antenna (32), a corresponding echo signal during the time interval that elapses between transmission of said radar pulse and transmission of the following radar pulse using the same antenna beam as the one used for transmitting the M radar pulses; c) carrying out elevation scanning cycles, wherein each elevation scanning cycle is carried out by repeating N times the operations a) and b) and by electronically changing, each time, the direction of pointing in elevation of the antenna beam so that, at each elevation scanning cycle, the radar pulses are transmitted towards, and the echo signals are received from, N swaths of the Earth's surface that are parallel to the direction of flight and are adjoining or partially overlapping, wherein N is an integer greater than one. All the radar pulses are transmitted: with a predefined pulse repetition frequency and a predefined timing of the scanning cycle such that to guarantee a complete coverage of each of the N swaths parallelly to the direction of flight; and by using a frequency agility technique.