Adaptive minimum variance coupled with sign and phase coherence factors in IQ domain for plane wave beamforming

In the framework of PICMUS challenge, the objective comparison between steered plane waves beamforming is proposed on an external platform. Our beamforming proposal consists in a weighted minimum variance approach which combines a phase coherence factor calculation and a minimum variance beamforming. The computation is made in the IQ domain in order to reduce the calculation effort. An adaptive scheme is used to optimize the number of elements that are considered for the MV beamforming, which depends on the depth and the lateral position of the reconstructed pixel. Moreover, the coherence maps are filtered in order to avoid strong discontinuities and speckle penalty on the platform. The obtained results on the MIDAS platform demonstrates higher CNR and resolution compare to classical DAS approach. The main limitation of our weighted MV lies on the final axial resolution which is not improved and limits the overall performance of the method.