Electronics design for high density CMUT array based ultrasound imaging system

Catheter;Ultrasound;Intracardiac echocardiography (ICE);FPGA;CMUT-on-CMOS;Transmit beamformer;Micro-coax cable;Time-division multiplexing (TDM);CMUT electronics

Rashid, Muhammad Wasequr ; Ghovanloo, Maysam Degertekin, Levent Hasler, Jennifer Electrical and Computer Engineering Inan, Omer Sabra, Karim Brand, Oliver Freear, Steven ; Ghovanloo, Maysam

University:Georgia Institute of Technology

Department:Electrical and Computer Engineering

关键词: Catheter;    Ultrasound;    Intracardiac echocardiography (ICE);    FPGA;    CMUT-on-CMOS;    Transmit beamformer;    Micro-coax cable;    Time-division multiplexing (TDM);    CMUT electronics;   

Others  :  https://smartech.gatech.edu/bitstream/1853/60180/1/RASHID-DISSERTATION-2017.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

In catheter based ultrasound imaging applications, gathering real-time imaging data from a large number of transducer array elements is extremely challenging withthe standard interconnect and transducer technology as there is a restriction on cable count due to the diameter of the catheter. Intracardiac Echocardiography (ICE)imaging systems require many cables connecting the transducer array elements at the tip of the catheter to the backend imaging systems. Reducing the number of cablesusing highly integrated front-end electronics, is essential for 3-D ICE imaging systems with 2-D imaging arrays. Cable reduction would also reduce the cost of the current2-D imaging ICE catheters with 1-D imaging arrays and can enable to ICE imaging under MRI by reducing the RF induced heating of the catheters. Current approaches to cable reduction tend to rely on area and power-hungry circuits to function, making them unsuitable for use in catheters. This research explores the design of the CMOS receiver circuitry which implements a Time Division Multiplexing (TDM) scheme toaddress the receive cable restrictions of the catheter. This approach, implemented in the form of a direct digital demultiplexing technique, allows for a reduction in thenumber of analog signal processing stages required. Receive multiplexing alone is not enough to reduce the cable count since the same elements in the arrays are used as transmitters. Therefore, the CMOS circuitry should integrate transmit beamformingas well. For this purpose, this study also explores an on-chip programmable transmitbeamformer circuit for producing focused and steered transmit beams. In this thesis, a system which uses an e cient real-time programmable on-chip transmit beamformercircuitry to reduce the cable count on the transmit side and analog 8:1 Time Division Multiplexing with Direct Digital Demodulation to reduce the cable count on the receive side is described and initial imaging results are presented.