| 摘要 |
Time gain compensation is provided in an ultrasonic scanner by storing a digital code in memory representing the desired signal gain for intervals of time during the reflected wave. Gain compensation due to transducer parameter can be provided in digital form in a separate memory, and the outputs of the two memories are combined and applied to a digital to analog converter. The resulting analog control signal is preferably filtered and then applied as a control signal to a gain control amplifier.
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