Polarization is the orientation of the radar waves that a SAR system can transmit and receive. SAR signals typically use polarizations where the signals can be horizontally or vertically aligned.
For single or co-planar polarization, both the transmitted and received signals use the same polarization.
HH polarization is useful for studying artificial and natural structures like buildings and tree trunks. It is suited for the following use cases:
- Urban and infrastructure monitoring
- Wetland and shoreline detection
- Vegetation and crop monitoring
VV polarization is useful for studying natural surfaces like soil and bodies of water. It is suited for the following use cases:
- Waterbody and sea ice detection
- Soil and non-urban monitoring
- Oil slick detection
For cross polarization, the transmitted signal is in one polarization, and the received signal is in the other polarization.
HV and VH polarizations are useful for studying volumetric targets like branches in trees, or trees in a forest. They are suited for the following use cases:
- Forest monitoring and biomass estimation
- Geological and subsurface analysis
- Urban area analysis
For dual polarization, the SAR system transmits and receives signals in both polarizations.
HH/VV polarization share similar properties with single polarization data, while providing more information about targets. It is useful for differentiating different types of surfaces and objects. It is suited for the following use cases:
- Agriculture and crop analysis
- Land cover classification
- Soil moisture estimation