Method and apparatus for echo-ultrasound imaging using compound AM-FM detection with increased dynamic range

摘要

A Compound echo-ultrasound imaging system in which the intensity of pixels in an image is a nonlinear function of the amplitude and frequency of echo signals. The dynamic range of a synchronous FM detector in the system is increased by effectively filtering from the echo signals all instantaneous frequencies which would produce intensity levels greater than a corresponding signal of equal amplitude at the carrier frequency of the ultrasound pulses. Filtering may be effectively accomplished by setting the Corner Frequency of the synchronous detector to the carrier frequency of the transmitted pulses.