Ultrasonic Echo Signal Acqusition And Transmission Design

Since the mid-1980s, medical ultrasound imaging technology has become one ofthe four modern medical imaging technologies; its development tendency is swift andviolent. As a representative of medical ultrasound imaging technology, B-modeultrasound imaging diagnostic technique has many advantages, such as painless, safewithout side effect, good real-time dynamic, rapid repetitive inspection and so on. Itbecomes one of the conventional diagnostic techniques at all levels of hospital clinicaland plays the role of the increasingly important in people’s daily life. At the same time,all-digital medical ultrasound imaging technology gradually becomes the mainstreaminstead of traditional analog imaging technology, its function is progressively powerfuland Integration is increasingly higher.In this dissertation, based on the B-mode ultrasound imaging theory and itstraditional implementation method, the all-digital B-mode ultrasound front-end signalacquisition and transmission system is studied in depth, reference XILINX, TI and othercompanies’ ultrasound system solutions, a128-element,48-channel B-type ultrasonicecho signals acquisition and transmission system design scheme is proposed, and thencorresponding circuit and verification work are completed.For B-mode ultrasound imaging synchronous data acquisition system which hasmany elements and channels, data acquisition inconsistencies among channels will havebad influence on echo signal characteristics and ultimately affect the imaging resolution.To solve this problem, multi-channel synchronous acquisition module is researchedin-depth, highly integrated8-channel ultrasound analog front-end is used, and samplingclock circuit is well-designed to significantly improve the sampling synchronization andmulti-channel amplitude and phase consistency. At the same time, the use of highlyintegrated front-end reduces the noise’ impact on the detection sensitivity of the systemsignificantly; enhance the system’s detection capability for the echo signal in thefar-field.For multi-channel signal acquisition and processing system, the data transmission bandwidth limits the size of the system and the implementation complexity. In thispaper, based on XILINX Virtex6FPGA SelectIO logic resources, a high-speed serialLVDS interface logic circuit is researched to realize48-channel,12bit samplingprecision ultrasonic pulse echo signal data reception and local storage, the system’sreal-time data processing bandwidth is up to3.6GB/S. To further meet the ultrasonicecho front-end signal information verification requirements, such as data analysis, beamforming, signal filtering, demodulation, image processing and so on, as well as thesubsequent algorithm research considerations, PCI-Express interface circuit based onFPGA PCI-Express hardcore endpoint module is researched, the circuit’s verification iscompleted to laid the foundation for the high-speed PCI-Express data transmission.To meet the system reliability requirements, the key signal’s PCB simulation isdone by Hyperlynx to ensure the signal integrity requirement of high speed signaltransmission. The simulation results and experimental results show that the systemachieves the intended functional requirements.