Digital scanning converter for medical endoscopic ultrasound imaging / 生物医学工程学杂志

This paper mainly introduces the design of digital scanning converter (DSC) for medical endoscopic ultrasound imaging. Fast modified vector totational CORDIC (FMVR-CORDIC) arithmetic complete coordinate conversion is used to increase the speed of ultrasonic scanning imaging. FPGA is used as the kernel module to control data transferring, related circuits and relevant chips' working, and to accomplish data preprocessing. With the advantages of simple structure, nice flexibility and convenience, it satisfies the demand for real-time displaying in this system. Finally, the original polar coordinate image is transformed to rectangular coordinate grey image through coordinate transformation. The system performances have been validated by the experimental result.

Coded excitation circuit on medical ultrasonic endoscope imaging system / 生物医学工程学杂志

In this paper, we introduce a coded excitation circuit for medical ultrasonic endoscope imaging system. This circuit is composed of TC6320 and its drive chip. The experiment demonstrates that this circuit can export frequency-adjustable, duration-controllable coded signals, and its voltage reaches +/-60 V. It still works well when excitant frequency reaches 30 MHz. Compared with the conventional medical ultrasonic pulse-echo imaging system, this coded excitation system has the potential of higher SNR and deeper penetration depth, especially for the small emission power system. This method has a bright future.

RovoIving ultrasonic probe for medical endoscope imaging system based on USB2.0 / 生物医学工程学杂志

This paper mainly introduces the design and implementation of rotary scanning imaging for Endoscopic Ultrasonography System based on USB2.0. The ultrasonic pulse-echo imaging technique has been used. In the paper, we simply introduce the emission circuit, receiving circuit and isolation circuit. According to the character of rotary scanning, we design the synchronous control circuit based on FPGA and data transmission circuit based on USB2.0. Finally the original polar coordinate image is transformed to rectangular coordinate grey image through coordinate transformation. The system performances have been validated by the experimental result gotten by scanning a specific object with continuous rotary motor.