Beam domain adaptive beamforming using Generalized Side Lobe Canceller with coherence factor for medical ultrasound imaging

摘要

As the medical ultrasound signals are not stationary, the radiation pattern of the corresponding input data does not have a specific shape. Thus, their reconstruction using adaptive beamformer (BF) become indispensable in order to improve the quality of the image. Generalized Side Lobe Canceller (GSC) is a robust realization against clutter and interference, resulting from an elegant representation of Linearly Constrained Minimum Variance (LCMV) and Linearly Constrained Minimum Power (LCMP) BF. As medical ultrasound imaging uses huge arrays, we emphasize transformations in the reduced spaces in order to diminish computational complexity, while achieving similar or higher levels of signal reconstruction quality. Such as array space (AS), GSC is realized in beamspace (BS). In order to enhance the quality of the reconstructions, we apply the coherent factor (CF), defined as an index of focusing quality determined from echo channel data in which the amplitude of image pixel is weighted.