Ultrasound pulser/receiver (P/R) system used to scan porcine patellae. (A) Experiment setup of the system including computer with A/D card and signal processing software, computer display, ultrasound pulser/receiver, container filled with the saline solution, and ultrasound transducer. (B) An enlarged view of the essential components in dashed circle in (A). (C) A typical sample of porcine patella. The dashed circle indicates the site scanned by ultrasound.