A high speed data acquisition and analysis system for ultrasonic energy measurements

摘要

A high-speed microcomputer-based data acquisition and analysis system was designed and constructed. The system was interfaced to an ultrasound sector scanner. The primary application of the system, in this case, was to measure the power spectrum of the backscattered (low-level) ultrasound signal from acoustic inhomogeneous media, such as liver tissue. The system was bench-tested and then tested successfully in normal operative conditions. The system digitizes the ultrasound signal, with sample rate of 16 Msample/s and stores the digitized data in a temporary storage (static random-access memory). When the temporary storage is full, the data is transferred to a microcomputer, where a fast Fourier transform algorithm is applied to calculate the power spectrum of the ultrasound signal. Pattern-recognition algorithms are applied to differentiate between normal and abnormal liver tissues using the acoustic attenuation coefficient as the differentiation feature.