Ultrasound imaging system with dynamic window function generator

Abstract

A phased array sector scanning ultrasonic system includes a separate receive channel for each respective element in an ultrasonic transducer array. Each receive channel imparts a delay to the echo signal produced by each respective element. The delayed echo signals are summed to form a steered, dynamically focused and dynamically windowed receive beam. A plurality of channels in the receiver are operated by respective receive channel control circuits to apodize the sampled echo signals produced by the transducer array elements with respective selected window function weighting factors as the echo signals are received. Each receive channel control circuit stores a set of window function weighting factors at successive address locations in a memory and includes an addressing circuit for producing an address useable by the memory to provide a desired window function weighting factor for each receive channel from the stored set. The addressing circuit produces a signal representing the derivative of the address, which is then integrated before being used to address the memory.