| 摘要 |
ULTRASOUND IMAGING SYSTEM FOR RELATIVELY LOW-VELOCITY BLOOD FLOW AT RELATIVELY HIGH FRAME RATES An ultrasound blood flow imaging system employing a moving-target-type Doppler processor having a passband extending from zero hertz to the repetition frequency of the pulses generated and processed during each beam. The system is able to image low-velocity blood flow by reducing the frequency at which pulses are generated and processed during each beam, thereby increasing the gain of the flow processor at low frequencies. In order to avoid a corresponding decrease in the frame rate, the ultrasound pulses for several beams are alternately generated and processed in interleaved sequence rather than generating and processing all of the ultrasound pulses for each beam before generating and processing ultrasound pulses for the next beam. |
