A programmable and compact open platform for ultrasound bio-microscope

Ultrasound bio-microscope is able to delineate small structures with fine spatial resolution on the order of several tens of microns. This paper presents the development of a real-time compact and open system for customized ultrasound bio-microscope studies. The system design was based on high speed FPGA embedded in compact printed circuit board (PCB) to achieve B-mode imaging and pulsed-wave (PW) Doppler imaging. Instead of hardware circuitries, most of functions were achieved with FPGA programs such as filter, envelope detector, digital scan converter (DSC), and complex fast Fourier transform (CFFT). The system structure could easily be modified by the user for customized applications. Testing results showed that the system could offer a minimum detectable signal of 25μV, allowing a 51dB dynamic range at 47dB gain. PCI interface included in the system allowed fast radio frequency (RF) data transfer and real-time imaging (over 500 frames per second). Phantom and in vivo imaging experiments were conducted and results showed good performance of system.