An airborne multi-function microwave remote sensing system has been developed in order to verify the design and performance of future Chinese spaceborne system. Future Chinese spaceborne microwave remote sensing system is for ocean research, atmosphere research and soil moisture content monitoring. Like spaceborne system, the airborne system also includes altimetry, scatterometry and radiometry functions. There are five operate modes: altimetry mode, scatterometry mode, radiometry mode, altimetry and radiometry mode, scatterometry and radiometry mode. The operate mode can be changed by program. There are five channels in radiometry mode. The altimetry mode, the scatterometry mode and the second channel of radiometry mode operate at the same Ku band. In the airborne system, the scatterometry mode uses two pyramidal horn antennae. One is for horizontal polarization. The other is for vertical polarization. The horizontal polarization antenna is also used in the altimetry mode. The radiometry mode uses five pyramidal horn antennae.
Flight experiments have been conducted on southern sea of China. The results verify the design and performance of the airborne multi-function microwave remote sensing system. They also show that the design of future Chinese spaceborne system is practicable. In this paper, the principle of airborne system is briefly introduced. Flight experiments and results are described.