Shih-Yang Wu

A VLSI design of singular value decomposition processor for portable continuous-wave diffusion optical tomography systems

In recent years, developments in diffuse optical tomography (DOT) technology have rapidly progressed in biomedical applications such as functional brain imaging. Furthermore, during the last decade, singular value decomposition has increasingly found many applications in the engineering field. Our goal is to develop a truly portable DOT system by utilizing system-on-chip design technique. In our DOT system, designing the SVD processor using VLSI technique is very efficient for solving the inverse problem in the DOT algorithm. In this paper, we focus on the hardware architecture design of the Jacobi singular value decomposition (JSVD) for applications in continuous wave diffusion optical tomography (CW-DOT) systems. The design is implemented using 90nm CMOS process technology and simulation results verify the functionality of the JSVD design within the developed CW-DOT system.

Advanced green energy system-on-chip design for portable diffusion optical tomography

In recent years, the rapid development of semiconductor manufacturing technology has made possible the large scale design and integration of many system level applications into a single chip. In this paper, we propose a portable computed tomography (CT) system to provide the general public easy access to a basic type of health check-up outside the hospital setting. The designed system employs diffuse optical tomography (DOT) technology, a technology which has found many successful applications in the field of biomedicine, such as breast cancer detection and observation of oxygenated hemoglobin distribution in the brain. In this paper, we develop a low-cost continuous wave near-infrared (CW-NIR) DOT system, paving the way for practical solutions in portable biomedical system-on-a-chip (SoC) applications. In addition, we demonstrate image reconstruction improvements associated with the two-dimensional (2D) post-processing technique employed in the proposed system.

Portable SoC design for CW diffusion optical tomography

In this paper, a digital signal processing system for image reconstruction of continuous wave diffusion optical tomography (CW-DOT) is proposed. Optical tomography systems employing near-infrared light can be used to detect oxygen concentration and impurities such as breast cancer in the human body. The proposed CW-DOT architecture is a truly appropriate system for further enhancing the possibility of miniaturization. The system is designed with the goal of high accuracy, low power and low cost for portable biomedical system on a chip (SoC) applications. Finally, the system has been verified on an SoC development platform, demonstrating fast and accurate reconstruction of two-dimensional (2D) DOT images.

A SoC design for portable 2-dimension oximeter image system

In recent years, many studies of 2-D oxygen saturation distribution reconstruction have provided easy access to human brain activity regions. However, only a few research focus on the home health care system using this technique. In this paper, we proposed a portable, low cost and real-time distribution reconstruction system of oxygen saturation in 2-D to make diagnosis at home possible. The system has been implemented in hardware as an oxygen saturation processor and verified on Field Programmable Gate Array (FPGA). Furthermore, we also introduce an image post processing unit to enhance the reconstruction result. Finally, we show that our system can recognize the variation of oxygen saturation region with high precision in detection tissue.

A Hardware Design for Portable Continuous Wave Diffuse Optical Tomography

In recent years, the rapid development of diffuse optical tomography (DOT) technology has made possible many successful applications in the field of biomedicine, such as breast cancer detection and observation of oxygenated hemoglobin distribution in the brain. In this work, we build an inexpensive and portable real-time continuous wave near-infrared (CW-NIR) DOT system hardware suitable for use in system on a chip (SOC) applications. With greatly reduced system volume, the system can pave the way for practical develop- ments in the clinical setting. The proposed system processes digitized biomedical signals acquired from a front-end sensor circuit, and can operate in either continuous or discontinuous mode according to user settings. Finally, we demonstrate the improvements in image reconstruction associated with the two-dimensional (2D) post-processing technique employed in the proposed system.

A wireless near-infrared imaging system design for breast tumor detection

In recent years, many near-infrared systems are used to detect breast tumor. However, the large instrument size and unfriendly interface make them hard to be accessed by users. In this paper, we proposed a portable, wireless and user friendly breast imaging system for breast tumor early detection. The system is implemented on self-designed platform combined with front-end sensors, DOT chip by TSMC 90nm technology, and commercial display devices. Furthermore, we confirm the functionality of the system by phantom testing.

A non-linear iterative method for multi-layer DOT sub-surface imaging system

Diffuse Optical Tomography (DOT) has become an emerging non-invasive technology, and has been widely used in clinical diagnosis. Functional near-infrared (FNIR) is one of the important applications of DOT. However, FNIR is used to reconstruct two-dimensional (2D) images for the sake of good spatial and temporal resolution. In this paper we propose a multiple-input and multiple-output (MIMO) based data extraction algorithm method in order to increase the spatial and temporal resolution. The non-linear iterative method is used to reconstruct better resolution images layer by layer. In terms of theory, the simulation results and original images are nearly identical. The proposed reconstruction method performs good spatial resolution, and has a depth resolutions capacity of three layers.

A high efficiency hardware design for real-time continuous wave diffuse optical tomography

Diffuse Optical Tomography (DOT) is a novel medical image technology with non-invasive method in the recent years. However, it has not been popular in clinical practice. In this work, a custom signal processing engine for Continuous Wave (CW) DOT is proposed, for the forward and inverse problem in the calculating procedure. To achieve the goals of small hardware size, low power consumption, and popularity, the design applied the Very-large-scale integration (VLSI) concept. In addition, the design is also implemented onto System on a chip (SoC) with a front-end sensor control, wireless communication, and a user friendly interface as a prototype of a health care monitor system. Lastly, we demonstrate a static phantom experiment to verify the functionality of the whole proposed system.

A novel near-infrared array based arterial pulse wave measurement method

Recently there have been many studies regarding pulse wave velocity (PWV) produced by near-infrared light. However, these studies have used multiple probes with the synchronization problem. This paper proposed a new detecting method to measure PWV on a radial artery with multiple channels in one front-end sensor array. The system was implemented on a MSP430F169 platform and the PWV result was transmitted by RS232 and displayed on the computer screen after being processed. Finally, the PWV result was measured to validate the functionality of the system.