Publikationen

Abstract: This paper introduces two protocols for communication in infrastructure networks consisting of a central server, stationary basestations and mobile devices. Mobile devices use IEEE 802.15.4 to communicate with the basestations. Among other things, the proposed protocols differ in their location management and in the routing of downlink and uplink packets. Through extensive simulations the protocols are compared with the focus on latency and packet loss metrics. The strength of each protocol depends on the traffic pattern caused by an application. This paper concludes with a recommendation for the usage of each protocol.

Abstract: In this paper we present a Digital Boarding Assistance (DigiBa) system for passengers in airport terminals. By providing navigation, notification and information services, passengers are enabled to move efficiently through the terminal. Based on functional requirements of such a system, the paper presents a prototype implementation on an embedded mobile device with restricted resources. Challenges concerning channel access in dense networks and indoor navigation on a device with limited hardware capabilities are outlined.

Abstract: Outdoor navigation services have become ubiquitously available due to small handheld devices such as GPS enabled mobile phones or dedicated mobile navigation systems. Two main drivers were necessary in order to provide widespread location based services: Acquiring positioning information with a certain degree of precision and widespread (mobile) access to computer networks to use the position information with a large information basis such as the Internet. Envisioned is a future, where indoor navigation and location based services are used as naturally as outdoor location based services are now. To achieve this long term vision where users seamlessly navigate for example from work desk to departure gate at the airport and use location based services on the way, various challenges have to be solved. In this paper, these challenges and open issues are discussed. The paper proposes an architecture which abstracts from different mobile devices and localization technologies. Additionally, it sketches the use of indoor topology information to increase the accuracy of indoor localization. These two presented concepts form a basis for a transition period until standards for ubiquitous indoor location based services have emerged.

Abstract: This report introduces three protocols for communication in infrastructure networks consisting of a central server, stationary basestations and mobile devices. Mobile devices use IEEE 802.15.4 to communicate with the basestations. Among other things, the proposed protocols differ in their location management and in the routing of downlink and uplink packets. Through extensive simulations the protocols are compared with the focus on latency and packet loss metrics. The strength of each protocol depends on the traffic pattern caused by an application. The report concludes with a recommendation for the usage of each protocol.

Abstract: This report describes usage scenarios of the architecture for indoor navigation and location based services (INLBS) developed in the Airport2030 project. The expandable architecture offers a framework and predefined services with a runtime environment and aims at enabling ubiquitous INLBS in any building with the users’ mobile device. The architecture consists of a mobile user platform (MUP) installed on mobile devices and a stationary facility platform (SFP) which is running on backend servers. For communication between MUP and SFP a communication and positioning infrastructure (CPI) is used. The SFP abstracts from different mobile hardware and communication and ranging technologies for ease of development. A runtime environment contains the service container which invokes life cycle functionality of the different services. Applications which are accessed from the MUP are developed using the services in the service container.

Abstract: The exploratory focus of the SomSed research field is the interdisciplinary research on self organizing mobile sensor and data networks. Since the founding of SomSed in 2007, great progress in scientific research has been achieved and much practical knowledge has been gathered using a prototype network permanently installed. This prototype network, from hereon referred to as CampusNet, is the basis for further investigations and offers the possibility to perform long term measurements in a large scale and real environment. The scope of this paper is to outline the current status of the SomSed research field and to briefly discuss future developments.