Abstract: An arbitrary waveform generator includes an arithmetic element that can access samples from a waveform sample memory and adjust values accessed from the waveform sample memory to modify waveform power or amplitude. In an illustrative embodiment of the arbitrary waveform generator, the arithmetic element is a multiplying digital-to-analog converter (DAC) that has a first input connection for receiving digitized waveform samples and has a second input connection for receiving a reference signal. An output signal from the multiplying DAC is a mathematical product of the digitized waveform samples and the reference signal. In one example, a reference digital-to-analog converter (DAC) generates the reference signal. In some examples, the digitized waveform samples are digitized samples of an analog waveform signal. In some examples, the arithmetic element is incorporated into the arbitrary waveform generator in a manner to maintain transmit signal resolution over a full range of transmit power settings.

Abstract: Circuitry for reducing side to side jitter in an ultrasound imaging system using a transducer which is mechanically scanned back and forth to cover the area to be imaged. The circuitry includes a filter circuit for providing a correction signal to be added to the transducer position signal. The filter circuit provides a phase lead proportional to the rate of change of the transducer movement. This signal is scaled by a factor which varies linearly as the depth being imaged changes. The correction signal compensates for delays through the transducer positioning and driver circuitry and for depth dependant delays resulting from the movement of the transducer during the scanning operation.