TOWARDS GNSS-R HYBRID COMPACT POLARIMETRY: INTRODUCING THE STOKES PARAMETERS FOR SMAP-R DATASET

The Soil Moisture Active Passive – Reflectometry (SMAP-R) is the first polarimetric L2C GNSS-R dataset collected from space. Given that the dataset consists of I/Q raw data, different processing techniques can be applied. In this paper we explore the calculation of the full polarization Stokes derived from the horizontal (H) and vertical (V) polarization measurements of the transmitted right-hand circularly polarized (RHCP) Global Positioning System (GPS) signal. This configuration is known as hybrid compact polarimetry (HCP) radar, in this case HCP of a bistatic radar or a GNSS-R instrument. This work describes how to use the collected data to obtain the full Stokes parameters and presents a glimpse to its value in the GNSS-R field, in particular the value of the phase of the cross-correlation signal between the H and V polarization measurements.