Gerhard Tröster

Electrical characterization of textile transmission lines

In this paper, electrical characterization and modeling of conductive textiles are presented. A dedicated measurement setup has been developed to allow reliable connection of the textile samples with the equipment cables. Geometrical fabric structures and fabrication tolerances as well as high frequency properties up to 6 GHz for four types of textiles have been determined. Transmission lines with controlled characteristic impedance have been realized enabling the characterization of typical line attenuation factors. This work shows that textile transmission lines can be used for frequencies up to 1.2 GHz and 120 MHz with the maximal lengths of 10 and 100 cm, respectively.

Wearable sensing to annotate meeting recordings

We propose to use wearable computers and sensor systems to generate personal contextual annotations in audio visual recordings of meetings. In this paper we argue that such annotations are essential and effective to allow retrieval of relevant information from large audio-visual databases. The paper proposes several useful annotations that can be derived from cheap and unobtrusive sensors. It also describes a hardware platform designed to implement this concept and presents first experimental results.

Optoelectronic interconnection technology in the HOLMS system

The High-Speed Optoelectronic Memory Systems (HOLMS) project, sponsored by the European Union Information Society Technology program, aims to make the use of board level optical interconnection in information systems practical and economical by developing optoelectronic packaging technology compatible with standard electronic assembly processes. To demonstrate the potential of the technology, we develop a demonstrator system that addresses the most pressing problem of contemporary computer architecture, memory latency. This paper describes the key ideas and some preliminary results of the HOLMS projects focusing on electronic interconnection technology, in particular optoelectronic packaging issues.

Kinetic energy powered computing - an experimental feasibility study

Kinetic energy is an attractive energy source for lowpower wearable systems. Several kinetic energy micro generatorshave already been modeled and fabricated. However,they have not been evaluated in the context of typicalwearable computing scenarios. This paper presents an experimentalapproach towards such an evaluation. For theevaluation, acceleration measurements were performed onseveral human test subjects while walking on a treadmill.Acceleration was measured and recorded at different pointsof the body. Subsequently, the amount of available outputpower was calculated based on a simple mechanical model.Based on the measured waveforms the upper limit of theoutput power is estimated to be around 200 µW dependingon the mounting position of the generator on the humanbody.

Experimental Evaluation of Variations in Primary Features Used for Accelerometric Context Recognition

The paper describes initial results in an ongoing project aimed at providing and analyzing standardized representative data sets for typical context recognition tasks. Such data sets can be used to develop user-independent feature sets and recognition algorithms. In addition, we aim to establish standard benchmark data sets that can be used for quantitative comparisons of different recognition methodologies. Benchmark data sets are commonly used in speech and image recognition, but so far none are available for general context recognition tasks. We outline the experimental considerations and procedures used to record the data in a controlled manner, observing strict experimental standards. We then discuss preliminary results obtained with common features on a well-understood scenario with 8 test subjects. The discussion shows that even for a small sample like this variations between subjects are substantial, thus underscoring the need for large representative data sets.

Multiprocessor system for high-resolution image correlation in real time

In this work, the correlation-based image localization problem is targeted toward implementation for real-time operation on high-resolution images. The main contribution resides in a global approach to the two-dimensional correlation problem which concurrently considers the algorithm, the system architecture, and its implementation. Analyzing and studying the alternatives concerning algorithm specification, VLSI architecture, and system architecture at different levels of the design phase, a scalable multiprocessor system, based on multiple instances of identical modules, is derived which achieves a real-time image correlation performance exceeding that of currently available solutions by an order of magnitude concerning frame-rate and input image resolution. As a result, the relevance of image correlation traditionally limited to the image processing domain is now expanded into applied machine vision applications. Addressing packaging and reusability aspects, an MCM implementation of the relevant system components is presented.

Modeling and optimizing the costs of electronic systems

Todays high-density packaging technologies make early attention to most factors essential in the design of successful products. A process-oriented, scalable cost-modeling tool, the Modular Optimization Environment (MOE), enables a continuous cost-quality-performance trade-off analysis throughout the design and manufacturing process.

Defocusing simulations on a retinal scanning display for quasi accommodation-free viewing

The limited depth of focus (DOF) is one of the main problems of todays head mounted displays. This paper investigates ways to overcome this drawback by using the retinal scanning technology. Based on an accommodation-dependent schematic eye model the contrast function of a retinal scanning display is evaluated as a function of eye accommodation, eye position and scanning beam width. The displays defocusing properties and the design trade-off between resolution, depth of focus and maximum image field are analyzed and discussed. The analysis indicates that an elliptically shaped scanning beam is most favorable to provide a quasiaccommodation free viewing. This elliptical beam shape is caused by the asymmetry in the scan pattern.

MM-wave microstrip patch and slot antennas on low cost large area panel MCM-D substrates-a feasibility and performance study

This paper analyzes the performance and feasibility of microstrip patch and slot antennas on low-cost thin film MCM-D in the MM-wave frequency range. The critical parameters of millimeter design such as losses, bandwidth, and radiation pattern are discussed based on EM modeling and design examples of microstrip patch and compact rectangular slot loop antennas in the frequency range of 40-85 GHz. Simple technology modifications are pointed out to overcome the basic limitations of the patch antennas on thin films such as low efficiency and low bandwidth. To perform this feasibility study, a finite element method (FEM) is used as a simulation tool and HP8510XF vector network analyzer (VNA) as measurement equipment.

New Route In System Integration: Chip-Package Codesign

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