AQUARIUS 4 Aquarius 4 Error analysis 4 Experiments 4 Microwave emission models 4 Observing system simulation experiments 4 Quantitative error analysis Remote sensing 4 Soil moisture 4 Soil moisture retrievals 4 Volumetric soil moistures 4 soil moisture 4 Arkansas Basin 2 Backscatter model 2 Backscattering 2 Computer simulation 2 Direct inversion 2 Error sources 2 High spatial resolution 2 Instrument noise 2 Land surface 2 Land surface models 2 Meteorological instruments 2 Microwaves 2 Observing System Simulation Experiment 2 Observing System Simulation Experiment (OSSE) 2 Parameter uncertainty 2 Radiative transfer model 2 Red Basin [United States] 2 Resamples 2