关键词: 超声成像, 声速不均匀性, 广义相干系数, 合成聚焦

Abstract: In medical ultrasound imaging field, in order to obtain high resolution and correct the focusing errors resulting from the sound-velocity inhomogeneities of the tissue, synthetic focusing imaging using the generalized coherence factor is presented. According to the characteristic of synthetic focusing, the echo data is processed by using twice generalized coherence factor. The received aperture data from single transmit array element is used to calculate the generalized coherence factor. The factor is used to weight the sum of received data to obtain single process result. All process results are processed using the generalized coherence factor again. The simulated results show that the method proposed in this paper in the aspects of resolution, contrast and correcting focusing errors is better than conventional DAS（Delay And Sum） and synthetic focusing algorithm.

Key words: ultrasound imaging, sound-velocity inhomogeneities, generalized coherence factor, synthetic focusing