A Design Of Axial Transmission Of Ultrasound Bone Densitometer

With the increasing aging population, more and more people are aware of the serious problem of Osteoporosis. Quantitative ultrasound technology has been widely used in domestic and international clinical for the advantages of low-cast, protable, simple operation, no-radiation, higher precision. Ultrasound axial transmission technique can measure long bone and uses cotrtical bone as a transmission medium. It attracts widespread attention and research as it has a high sensitivity to the changes of bone mineral density and can effectively eliminate the potential impact of soft tissue. This paper does some research and exploration in the field of bone density measurement and ultrasound testing technology, it describes the principles and applications of axial transmission technology based on critical angle side wave. Moreover, it designs a detection system including both the function of ultrasound signal collection using FPGA as the core and signal processing in PC.This paper describes the research status of bone density measurement technology at home and abroad, introduces some detection methods used in quantitative ultrasound technology and axial transmission technology in detail. Then it introduces the overall system design, and on this basis, it describes the specific application of the hadware and software design.In this paper, ultrasound bone densitometer, as a portable equipment, uses USB 5V power supply to reduce the size of the acquisition system, and designs the probe detection circuit to achieve the probe automatic recognition. A transmitting circuit and a receiving circuit aim to achieve the function of ultrasound transmission and echo reception. USB module realizes the data transmission between FPGA and PC. The software system in PC is respondible for the automatic gain control to the front end and echo filtering, followed by the calculation of sound speed. Furthermore, the application software is also responsible for patient information management and printing report.The entire testing process indicates that the measurement results and the technical indicators meet the requirement. System measurement to radial bone has a high accuracy and reliability. Finally, the system analyzes the existing problems and suggestions for improvement.