A wide-band six-port polarimetric measurement system

Measurements of the polarization state of an incoming wave and the polarimetric scattering matrix (PSM) of a scattering target can be grouped into two approaches: direct (or coherent) approach and indirect (or incoherent) approach. The direct approach involves the measurement of both amplitude and phase data using a coherent receiver or a vector network analyzer. The indirect approach measures a number of amplitude (or power) values to derive the relative phase information. The six-port network analyzer belongs to the indirect approach. A wide-band six-port polarimetric measurement system with the use of two dual-polarization antennas is developed as a polarimeter to measure the polarization state of an incoming wave, and also as a polarimetric scatterometer to measure the PSM of a scattering target.