Fig. 2
From: Sidelobe reduction for plane wave compounding with a limited frame number
Different distances of two samples: a Euclidean distance, b effective distance. The black rectangle represents the central sample and the black circle represents the sample requiring the distance computation with the central sample. In a the circles in pale gray means the other samples are dismissed when calculating the Euclidean distance. In b the circles in dark gray means the other samples are considered when calculating the effective distance. Also, the effective distance is directed