Department of Electricaland Computer Engineering
Faculty of Engineering & Architectural Science
Model-based Design of a Multichannel Wireless Impedance Sensor Readout Unit
2021 Research Internship Project
Faculty Name
Project Title
Model-based Design of a Multichannel Wireless Impedance Sensor Readout Unit
Project Description
Electrical impedance spectroscopy (EIS) is a powerful analytical tool with a wide range of medical applications, including biosensing, cancer detection, DNA analysis, cell and tissue characterization. Impedance spectroscopy exploits frequency-dependent characteristics of biological samples, to measure several parameters related to their electrophysiological and mechanical properties. The purely electrical nature of impedance measurements is a key benefit compared to mechanical and optical measurement systems, supporting the design of simple readout instrumentation and direct integration in CMOS technology. The functionality of impedance readout circuits can be further enhanced by the addition of wireless powering and data transfer capabilities, thus extending their use to wearable and implantable devices. Impedance readout approaches include synchronous or phase-sensitive detection, phase and magnitude measurement, resonance-based and time-mode measurements. Among these methods, time-mode techniques present several benefits in terms of lower power consumption, sensitivity, high-speed operation, and compatibility with power-efficient wireless modulation schemes. This project will focus on a model-based design of a wireless multichannel time-mode impedance readout unit. The design of the model will include the adoption of pulse-width and pulse-position modulation schemes to encode impedance data from an array of sensors. The project will also investigate methods for power-efficient wireless transfer of multiplexed time-based impedance data to a remote unit. The project is part of research activities in the design of low-power wireless implantable sensors and will support the definition of system-level approaches in the design of wireless impedance readout units.
Student Responsibility
The student responsibilities include: (a) Familiarize with the different impedance measurement methods; (b) define a system-level diagram of a time-domain impedance readout system, construct a model and perform behavioural simulations of the readout system; (c) model and investigate the effect of non-idealities (drifts, noise, power levels, offset and parasitics) on the performance of the readout unit; (d) combine the model of the readout system with a model of a simple wireless unit (based on inductive coupling) for power and data transfer; (e) perform transient simulations of the complete wireless readout unit.
Specific Requirements
(a) Solid background in electrical and electronic circuits (e.g ELE404, ELE504, EES604), (c) practical experience with Matlab and (desirable) Simulink simulation environments.