Weighted least squares DORT method in selective focusing

Abstract

The DORT (decomposition de lpsilaoperateur de retournement temporel) method is an efficient technique to focus signal on the target. The DORT method requires the measurement of the inter-element impulse responses of the propagating medium for all pairs of elements in the array. The time reversal operator (TRO) is deduced and diagonalized from these responses. But DORT method has worse results in non-ideally resolved scatterer case that two scatterers are placed close with each other. Therefore, in this paper, weighted least-squares (WLS) combining with the DORT method are proposed to perform selective focusing in non-ideally resolved scatterer case. This technique can also perform target focusing with higher spatial resolution than original DORT method and faster computation than adaptive beamforming method.