Tenders Are Invited For Derivation Of Spaceborne Mission Requirements For Soil Moisture Retrieval With Closure Phase

Tenders are invited for Derivation of Spaceborne Mission Requirements for Soil Moisture Retrieval with Closure Phase Expro+ Re-Issue Surface soil moisture can be retrieved from SAR backscatter data; however, these techniques are sensitive to surface roughness changes and extensive spatial averaging is required. In the last years, a significant amount of work has been done to establish a framework for the retrieval of surface soil moisture from InSAR products. It is hereby proposed not to use the interferometric phase directly, since interferometric phase measurement are also sensitive to many other contributors (atmosphere, deformation, orbital errors,...), but to use the so-called closure phase. The closure phase is the cyclic product of spatially averaged interferograms between a combinations of three SAR acquisitions. The idea is to increase the accuracy to of surface soil moisture measurements by using theclosure phase method or by combining the closure phase method with amplitude-based techniques.Currently, there exists no mission dedicated to providing surface soil moisture products, which are retrieved from closure phase stacks. Even though ideas for such a missions exist, quantified Level-1 performance requirements that are compatible with the required surface soil moisture measurement accuracy when using this technique are not yet available. During this activity, a simulation tool shall be developed to systematically analysing the surface soil moisture retrieval performance from closure phase stacks in dependence of Level-1 product performances, instrument and mission parameters and scene parameters. After implementation and validation, this tool shall be used to analyse the sensitivity of the surface soil moisture retrieval performance as a function of the different Level-1 and system parameters. Further, this tool shall incorporate different models to analyse how the results depend on them. The performed analysis shall be used to derive instrument, mission and Level-1 performance requirements to achieve the best moisture estimation performance from closure phase stacks. The derived requirements shall be used to formulate recommendations for future mission ideas targeting the surface soil moisture retrieval from closure phases. The goal of this activity is to achieve a systematic analysis of the requirements, limitations and error sources of the closure phase techniques for surface soil moisture retrieval. Read less Tender Link : https://esastar-publication-ext.sso.esa.int/ESATenderActions/filter/open