Development Of Low Frequency Ultrasound Thoracic Imaging System

With the continuous progress of medical technology,the role of ultrasound imaging technology in diagnosing human lung diseases is becoming increasingly important.In examining lung diseases,traditional high-frequency ultrasound diagnostic equipment has certain limitations.In contrast,low-frequency ultrasound has become an essential alternative due to its intense penetration and good transmission characteristics.Low-frequency ultrasound usually uses frequencies below 1MHz,which can achieve real-time monitoring of oxygen and moisture in lung tissue.It has obvious advantages in the early prevention,treatment,and diagnosis of chest lesions.The research on the transmission of low-frequency ultrasound imaging technology mainly focuses on imaging algorithms and ultrasound signal processing.However,there needs to be more research on low-frequency ultrasound imaging equipment.Therefore,this thesis develops a low-frequency ultrasound imaging system and a Piezoelectric transducer that can be used for low-frequency ultrasound chest imaging.The research content of this thesis is as follows:An ultrasonic transducer for transmission of low-frequency ultrasound chest imaging was studied.The equivalent mechanical and electrical network of the probe was obtained by analyzing the electrical and mechanical aspects.Complete the research of the 40 KHz ultrasonic transducer research through theoretical formulas,sound velocity,and other parameters,and verify the transducer’s performance using COMSOL multi-physical field platform and using COMSOL to establish a thoracic cavity model,conduct emission and reception tests on the transducer,and obtain simulation data of low-frequency ultrasound transmission through the thoracic cavity.Develop a data acquisition system with embedded chips as the core,and a sensing system consisting of 16 PGA460 ultrasonic transceiver modules and probes.The embedded host serves as the core for gating control of the ultrasonic transceiver array module.The transceiver array module with PGA460 as the core completes the functions of ultrasonic excitation signal transmission,ultrasonic data acquisition,and data processing.Finally,the data is transmitted to the imaging computer through the embedded host.Develop software for low-frequency ultrasound imaging systems.The upper computer software system is implemented using MATLAB,which communicates with an embedded data acquisition system to obtain low-frequency ultrasound transmission data.The image reconstruction is completed using algebraic reconstruction.The experimental results show that the parameters and data acquisition system of the ultrasonic imaging probe developed in this study can obtain adequate low-frequency ultrasonic chest imaging data,and the imaging system software can obtain reconstructed images.