Spaceborne SAR tomography over forests: Performance and trade-offs for repeated single pass polinsar acquisitions

Continuous development, experimentation and validation activities with airborne campaigns pushed towards the proposal of spaceborne missions that could implement SAR Tomography (TomoSAR) on a global scale. Together with innovative SAR imaging modes, TomoSAR plays an essential role in forest mapping for the characterization of 3-D structure and its dynamics at high spatial and temporal resolutions. In this framework, the characterization of the structure information content of multibaseline (MB) data stacks is of fundamental importance in order to shape both system design and acquisition concepts. In this paper, MB acquisition tradeoffs are analysed in representative forest scenarios fixing a given performance in the estimation of the parameters characterizing the vertical structure. In addition, the benefit against temporal decorrelation of repeated MB single-pass interferometric acquisitions is quantified with respect to repeat-pass acquisitions, and the role of polarization is discussed.