| 摘要 |
When an ultrasound transducer is driven by a signal that contains a relatively wide range of frequencies, the frequency-dependent attenuation characteristics of the subject being imaged can be relied on to simultaneously provide, using only a single pulse per line of the image, (a) a return from the deeper portions of the image that is dominated by lower frequencies and (b) a return from the shallower portions of the image that is dominated by higher frequencies. These returns are processed into an image with higher resolution in the shallower parts, and lower resolution with adequate SNR in the deeper parts. |
