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Locating Users in Mobile Communication Systems

General Topic

Location based services are services which provide an additional value by combining position information of users with database information. Examples for location based services are routing services like Google maps or context (in this case location) based advertisement in social networks like Facebook. Several different approaches for determining user positions are available. Today user equipment based approaches like wireless assisted GPS (WA-GPS) positioning is dominant. Network based positioning that uses radio signal information (like time difference of arrival (TDOA)) and network system information (like the cell global identifier (CGI)) is not in wide spread use for private location based services. Nevertheless network based positioning is in use in case of emergency calls or police actions.

Company

In 2001 I worked for six months as an intern for „Mannesmann Pilotentwicklungsgesellschaft mbH” (mpe) in Munich (Bavaria). The mpe was part of the R&D infrastructure of the former Mannesmann AG (today: Vodafone) and was responsible for pilot development projects. The purpose of mpe was the interdisciplinary search for new technologies and to assess their applicability for product innovations in different Mannesmann departments. Main fields of research of mpe at that time were wired and wireless communication technologies as well as hydrogen fuel cells.

Task

My task was to support a research team which investigated ways of improving network based positioning approaches. I had to prepare and carry out experiments which collected network information and GPS data in parallel. Afterwards my task was to evaluate the collected data by means of visualization. My work was based on an already available experiment setup which had to be extended for the collection and decoding of cell information and GPS data streams. For visualizing the data I used Agilent OneLab for the transformation of location data and Visual C++/ActiveX for the graphical output.

Gained Experience

Because of the self-reliant nature of my task I have improved my self-organization skills and I have got profound knowledge of network based positioning methods and related knowledge like geographical coordinate systems as well as the operation principles of cellular networks. This knowledge was afterwards deepened in an advanced seminar with a similar topic at the Ilmenau University of Technology. I have improved my knowledge in JAVA and C++ programming and I have gained experience in collecting and decoding serial data streams of small mobile devices.

For your further information a summary of my work at mpe can be found here. The additional information of the advanced seminar can be found here. The documents are provided in German. Please see this link for legal notices and please keep in mind that these are the first scientific documents I have created on my own.