Experiments for an integrated precise airborne navigation and gravity recovery system

Experiments performed in August 1989 to investigate the possibility of integrating different sensors for precise position determination and airborne gravity field recovery are reported. The tests were carried out with a DO 128 research aircraft over the North Sea and also over test areas in Northern West Germany. Precise differential positioning of the aircraft was performed using two different GPS (Global Positioning System) receiver types simultaneously. A Sercel TR5SB C/A-code receiver and a T14100 P-code receiver were installed in the aircraft, while a third and fourth receiver of the same types were tracking satellites on the ground. The system onboard consisted further of a ring laser gyro strapdown system allowing precise position and attitude determination by interpolation between GPS updates. For the purpose of airborne gravimetry the system was equipped with a Bodenseewerk KSS 31 gravity meter. The determination of high-frequency height variations was possible using a precise laser altimeter. A quick-look analysis of the data and velocity determination in the centimeter-range using GPS is presented