George Jie Yuan

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Electric-field intrabody communication (EF-IBC) is a promising new scheme for the data exchange among wearable biomedical sensors. It uses the body as the signal transmission media. Compared with existing body area network (BAN) schemes, EF-IBC can achieve higher data rate with less transmission power. Until now, the detailed EF-IBC channel mechanism is not(More)
Wearable and implantable medical sensors have been investigated continuously in recent years to provide better diagnostics and monitoring for personal health care. Much attention has been drawn to the establishment of the ubiquitous body area network (BAN) to reliably connect the body sensors and collect the sensor data in real time. Electric-field(More)
 Abstract—The dual-band recording of the local-field potential (LFP, 0.1Hz~200Hz) and the spike potential (SP, 200Hz~10kHz) is important for physiological studies at the cellular level. Recent study shows that the LFP signal plays important roles in modulating many profound cellular mechanisms. Although various bio-signal acquisition circuits have been(More)
A systematic design methodology for high-performance gain-boosted opamps (GBOs) is presented. The methodology allows the optimization of the GBO in terms of ac response and settling performance and is incorporated into an automatic computer-aided design (CAD) tool, called GBOPCAD. Analytic equations and heuristics are first used by GBOPCAD to obtain a(More)
Microelectrodes are widely used in the physiological recording of cell field potentials. As microelectrode signals are generally in the μV range, characteristics of the cell-electrode interface are important to the recording accuracy. Although the impedance of the microelectrode-solution interface has been well studied and modeled in the past, no effective(More)
The linearity of a high-resolution pipelined analogto-digital converter (ADC) is mainly limited by the capacitor mismatch and the finite operational amplifier (OPAMP) gain in the multiplying-digital-to-analog converter (MDAC). Therefore, high resolution pipelined ADCs usually require high-gain OPAMP and large capacitors, which causes large ADC power. In(More)
A new all-digital background calibration method, using a piecewise linear model to estimate the stage error pattern, is presented. The method corrects both linear and nonlinear errors. The proposed procedure converges in a few milliseconds and requires low hardware overhead, without the need of a high-capacity ROM or RAM. The calibration procedure is tested(More)
High-speed CMOS imaging sensors (CIS) normally have low sensitivity because of the large integration capacitance. They also have high noise because pixel circuits cannot implement correlated double sampling (CDS) to remove the pixel reset noise. For applications, such as micro-computed tomography (micro-CT), this is a major limitation. In this work, we(More)