Spread spectrum coding for ultrasound contrast agent imaging

摘要

Contrast agent imaging uses spread spectrum coding. The contrast-to-tissue ratio and signal-to-noise ratio for contrast agent imaging is improved by transmitting a waveform with pulses at two or more frequencies. In one embodiment, signals received at an intermodulation frequency responsive to the two transmitted frequencies are isolated and used for imaging. As a result of the differences in responses of contrast agent and tissue to the frequency transitions between pulses, information from contrast agent with minimal influence from tissue is identified. In another embodiment, two waveforms with pulses at two or more frequencies are sequentially transmitted.