Modelling and analysis of rain effect on Ka-band single pass InSAR Performance

The adoption of Ka-band for performing SAR interferometry is considered very promising since it could provide the possibility to embark the full instrument within a single satellite. However, one of the major concerns of the effectiveness of spaceborne Ka-band radars is the impact of the atmosphere, and, in particular of precipitation on the instrument performance and availability. This paper analyzes the impact of precipitation on the performance of Ka-band across-track InSAR. In order to assess the rain impact on the InSAR random height error, the paper proposes an extended form of the interferogram coherence. The paper shows that, for the reference instrument configuration investigated, a random height error compatible with HRTI-3 specification can be met under moderate rain condition.