Radar satellite and radar satellite system using radar satellite

A radar satellite comprising:

• a radar unit including a plurality of radar panels coupled to each other in a single flat plate shape, each of the plurality of radar panels including:
• a plurality of antennas which transmit and receive radar waves, and
• a solar cell;
• and
• a communication unit which performs communications with a spot on an earth or a spacecraft, wherein:
• when the plurality of antennas transmit radar waves, the transmitted radar waves are phase-controlled and synthesized according to a predetermined computer program or a command received from the spot on the earth;
• a synthesized transmitted wave corresponding to a size of the radar unit is emitted from the radar satellite to scan an earth surface and an airspace above the earth surface, with the proviso that
• the synthesized transmitted wave emitted from the radar satellite is configured to scan a wide range of the earth surface such that, when one radar satellite revolves along an equatorial orbit and another radar satellite revolves along a polar orbit, the whole earth surface is scanned;
• received radar waves reflected from the earth surface and the airspace are converted by a signal processor into data for image without being synthesized, and the data for image is output to the communication unit;
• and
• the radar unit includes:
• a radar panel array which is a plate-shaped structure including the plurality of radar panels;
• and
• a deployable truss structure including a plurality of side frame members supporting the plurality of radar panels, respectively, and coupled to each other in such a manner that the plurality of side frame members are foldable and deployable.