Review of Current Simple Ultrasound Hardware Considerations, Designs, and Processing Opportunities

Ultrasound is one of the most widely used imaging tools for non-destructive testing (NDT) and non-invasive medical diagnosis. Since its beginnings in the 1950s, ultrasound imaging research has led to innovations such as new sensors, signal processing, and hardware development. After more than fifty years, the field continues to evolve, aided by advances in electronics and digital hardware. However, the field remains under-researched in terms of experimental open-source hardware. An open, flexible, and cost-efficient platform is still needed for many basic medical and testing applications. A platform of this kind would support the efforts of researchers, makers, and device developers in accelerating ultrasound research and development. The aim of this review is to identify literature relevant to the understanding, design, and operation of simple ultrasound devices and to present this body of knowledge in a format that is easily accessible to ultrasound system designers. It also provides a summary of current ultrasound research to introduce readers to trends of interest. We capture design and use considerations from classical and modern instruments. We cover both NDT and medical applications, starting with a review of the design context, followed by a review of existing architectures and analog buildings blocks, followed by a survey of digital options available to support and complement the hardware.