Radar imaging with very low grazing angles in a bistatic forward-looking configuration

The acquisition of Synthetic Aperture Radar (SAR) data in a bistatic forward-looking configuration offers many new capabilities for a broad spectrum of remote sensing applications. A radar system in an aircraft could image the runway during the landing approach to improve landing safety, particularly in poor visibility conditions. First experiments and imaging results demonstrate the feasibility of forward-looking bistatic radar imaging even with a very low elevation angle to the receiver, which is in the order of four degrees for a typical landing approach. The paper presents the challenges of imaging in forward direction and shows experimental results with a moving ground-based transmitter and an approaching aircraft. The experiments have been conducted to demonstrate the suitability of forward-looking SAR to improve the safety of aircrafts landing under low visibility conditions.