A Quad-Pol SAR Imaging Mode with Sound Azimuth Ambiguity

The azimuth ambiguity of the cross-polarized (cross-pol) echoes of hybrid quadrature-polarimetric synthetic aperture radar (quad-pol SAR) mainly comes from its co-polarized (co-pol) echo signals in the odd ambiguity regions. Here to improve the azimuth ambiguity of hybrid quad-pol SAR, a SAR imaging mode that alternately transmits the orthogonal elliptically polarized (OEP) waves to weight these co-pol echoes is detailed. Moreover, the boost of SAR azimuth ambiguity is described by the azimuth ambiguity-to-signal ratio (AASR) and evaluated by the L-band system parameters of spaceborne SAR. In addition, the chirp scaling algorithm (CSA) is adopted to execute the scene simulation experiments. And the results demonstrate that the presented SAR imaging mode can suppress the azimuth ambiguity of hybrid quad-pol SAR and verify the theoretical analysis.