Potential and limitations of forward-looking bistatic SAR

Bistatic synthetic aperture radar (SAR) operates with spatially separated transmit and receive antennas that are mounted on separated platforms. Provided that there is an overlap of both antenna footprints, the platforms can move with different velocities in arbitrary directions. A special configuration is given, when the receive antenna looks in forward direction, which is called bistatic forward-looking SAR. Besides the well known advantages of bistatic SAR like the increased information content of the data because of different RCS and scattering characteristics, such a configuration enables high resolution imaging in forward direction, which is not possible with conventional monostatic SAR systems. This paper analyzes a bistatic forward-looking configuration and demonstrates the capability and feasibility of imaging in forward or backward direction using the radar satellite TerraSAR-X as transmitter and the airborne SAR system PAMIR as receiver.