Dagmar Peters

A novel circuit concept for PSK-demodulation in passive telemetric systems

A PSK-demodulator for a bi-directional data transmission in passive telemetric microsystems is presented in this work. These systems, which use the telemetry link for energy and data transmission, are based on identification systems, which use ASK-modulation for both data transfer directions. This leads to problems with a bi-directional data transmission in sensor applications, where the power consumption is significantly higher than in identification systems. A system that uses a PSK to transfer data into the microsystem to improve the energy transfer during data transmission is presented. The key component of this system is a novel PSK-demodulator, which works without an internal oscillator and therefore no PLL is needed. The major advantages of the presented system are the self-adaptation to the carrier frequency and the independence of the demodulator of parameter drifts.

MODOS - model based design optimization system

Model based design optimization is becoming a very important task. The continuous reduction of technologically realizable dimensions leads to growing coupling and interaction between system parameters. The complexity of microand future nanosystems is growing permanently while production parameters are subject to fluctuations. In order to take. advantage of the new technologies strengths the development process needs to be supported by sophisticated optimization tools like the one presented in this work.

Calculation of inductances and capacitances for 3D structures using Prony's method

A closed form expression for the electrical field of a line source over a multi-layered material can only be derived fro special geometries and cases. The use of the spectral domain, but this expression can normally not be transferred back into the space-domain. The solution is an approximation in the spectral domain by use of exponential terms which can easily be transferred back into the space-domain. This is done by use of Pronys method. The number of exponential terms has to be correctly estimated to avoid numerical difficulties. This paper presents a sophisticated method to determine the necessary number of exponential terms and shows how this approximation can be used to calculate inductances and capacitances for conductors with rectangular cross-sections.

An Application Specific Design Methodology for Microsystems

A fundamental approach to a coherent design strategy for microsystems is presented in this paper. Establishing such a concept can provide undeniable advantages concerning manpower, technical resources and development time. Prevalent design steps are discussed in detail, referring to the suggested ideas. Several microsystem applications and software tools are taken into account to illustrate the main aspects of a consistent design flow.The approach of behavioral physical modelling in combination with model based design optimization applying efficient and robust numeric methods in both fields allows pre-production optimization. Thus, overall development and redevelopment effort can be reduced significantly.

Modular concept for the design of application-specific integrated telemetric systems

Modern microsystem technology generates a great variety of very small sensors and actuators. With the use of capacitive measurement or moving principles these components have a very low power consumption and with some data preprocessing they can be used in passive telemetry systems, which need no integrated battery. Instead, they use two loosely coupled coils to realize the energy transfer. To create very small systems, e.g. for the implantation inside the human body, the use of an application specific integrated circuit for the telemetry will be necessary. In this paper a design strategy for the realization of implantable telemetric microsystems and a building set with different blocks for the creation of an application specific telemetry chip is presented. In addition to the necessary main building blocks like rectifiers, voltage regualtors and blocks for the uni- or bi-directional data transmission the set also includes some supplementary blocks like an auaotmatic resonance adjust. All blocks are realized in a standard CMOS process (a 0.7 um CMOS process with some analogue add-ons) and therfore very small and cheap systems can be created.

Application-specific design methodology for microsystems

A fundamental approach to a coherent design strategy for microsystems is presented in this paper. Establishing such a concept can provide undeniable advantages concerning manpower, technical resources and development time. Prevalent design steps are discussed in detail, referring to the suggested ideas. Several microsystem applications and software tools are taken into account to illustrate the main aspects of a consistent design flow. The approach of behavioral physical modeling in combination with model based design optimization applying efficient and robust numeric methods in both fields allows pre-production optimization. Thus, overall development and redevelopment effort can be reduced significantly.

Theoretical basis for including small as well as large deflections of quadratic membrane structures in one behavioral model

Membrane structures are one of the most common elements in microsystems. In order to be able to perform system simulations, behavioral models of their bending lines have to be developed. These models may also be used as a basis for parameter extractions which is a crucial task in the development of microsystems. But parameter extractions can only be performed, if the models used include all of the most important physical effects. Hence, the physical basis of these models has to be very profound.

Model-based optimization of Medical Test Strips

Medical Test Strips made from plastics can provide a cheap and reliable analysis of body liquids. The underlying microsystem contains structured micro-channels to adjust the filling time as an important parameter for chemical reactions. Columns or lamellae of some /spl mu/m dimensions are placed in the channel to define the fluidic resistance, which is influenced by the pitch between these structure elements as well as by their shape. As no analytic solution exists to describe the microfluidic interaction, the authors have been following approaches based on discrete partial differential equations and behavioural descriptions to obtain a simulation model. Model-based optimization has been performed to get useful sets of parameters to be handed to the industrial partner for manufacturing and therefore verification of the calculated results.

Computer aided design of a radiometric system for material sheet production

Material sheet production speed and precision has increased in the former decades. This is partly due to improved monitoring of production process core data. Critical data in this respect are the materials edge position and the mass per unit area over the materials width. This paper demonstrates a new design that allows full monitoring of the whole material without moving parts. A model for this system, the multi electrode ionisation chamber (MEIC) is presented.

Parameter identification and macromodeling of hysteresis phenomena

A parameter identification method for a macro model of hysteresis phenomena is illustrated. The chosen model is based on the theory due to Jiles and Atherton. In contrast to the Jiles-Atherton model (JA) the here chosen model does not show the JAs problems with the frequency dependence of the coercivity. A methodology well known from modeling electronic circuits has been chosen to utilize the illustrated model for the simulation of hard magnetic core materials applying parameter extraction methods based on parametric optimization.