Studien-, Diplom-, Master- und Bachelorarbeiten We assign and supervise work on the subject:
Current Topics (Aktuelle Themen)
Opportunistic Routing Opportunistic routing (OR) is a new and promising routing technique for wireless multi-hop mesh networks. The key idea behind OR is overhearing packets and cooperation among relaying nodes. OR works well in networks with high node density such as mesh or sensor networks. OR enables routing along multiple routes as well as dynamic relay selection, thus, it obtains higher link reliability and larger transmission range. The following research is required to improve OR: Power control & bit-rate selection for OR Multi-flow rate control for OR Multi-channel support and OR Impact of (low) mobility on OR Dynamic switching between OR and selection diversity (SD) Impact of (PHY) antenna diversity on OR
Requirements: Credits: Seminar paper (Studienarbeit) or Master thesis or Bachelor thesis Contact: Dr. Zubow (zubow@informatik.hu-berlin.de) Vergleich von Broadcast-/Flooding-Verfahren Studienarbeit Implementierung von verschiedenen Broadcast-Protokollen mit Hilfe des Click-Frameworks Evaluation im Simulator (JiST/Swans) und auf Hardware (Atheros) Zu beantwortende Fragen: Vergleich der Verfahren in Hinsicht auf Zuverlässigkeit, Verzögerung und Resourcenverbrauch ? Voraussetzung: Kenntnisse in C, C++ Kontakt: sombrutz@informatik.hu-berlin.de
Vergleich von DHT-basierten Routing-Protokollen in drahtlosen Ad-hoc-Netzwerken Studienarbeit, evtl. Diplomarbeit Implementierung von mehreren Routing-Protokollen welche auf einer verteilten Hashtabelle (DHT) basieren. Vergleich der Protokolle mit Hilfe eines Simulators (JiST/Swans) and im Testbed (Atheros). Voraussetzung: Kenntnisse in C, C++ Kontakt: sombrutz@informatik.hu-berlin.de
Implementierung von 802.11h/k/v Studienarbeit Implementierung mit Hilfe des Click-Frameworks Evaluation im Simulator (JiST/Swans) und auf Hardware (Atheros) Zu beantwortende Fragen: Inwieweit unterstützt gängige Hard-/Software die Standards ? Wie kann dies für die Unterstützung von Kanalzuweisung in 802.11 Infrastruktur Netzwerken genutzt werden ? Voraussetzung: Kenntnisse in C, C++ und Java Kontakt: sombrutz@informatik.hu-berlin.de
Evaluation von Software Radios (Calradio) Studienarbeit Einarbeitung in die Hard- und Software eines Software Radios Evaluation der Hardware: Was leistet die Hardware ? Entwicklung eines Frameworks zur Entwicklung neuer MAC-Protokolle mit Hilfe eines Software Radios Voraussetzungen: Kenntnisse in C, Erfahrung mit eingebetteten Systemen Kontakt: sombrutz@informatik.hu-berlin.de
Vergebene Themen Loss Type Aware Rate Selection in Wireless Networks Conventional rate selection algorithms do not take into account different types of packet loss. Lowering the data rate, i.e. using a more robust modulation, is not always a solution to compensate for loss. In the case of loss due to collisions or interference (e.g. hidden node), reducing the data rate will increase the packet length. This will increase the chances of collisions since it takes more time to transmit a packet. Our approach is to gather statistics to be able to distinguish between both causes of packet loss so that a rate selection algorithm is able to react in a proper way. The goal of this work is to develop and evaluate a rate selection algorithm which adapts the data rate depending on the reported loss type. The developed algorithm has to be compared with existing state-of-the art algorithms. Requirements: Credits: Contact: In Search of a Packet Loss Discriminator The goal of this work is to search for a packet loss discriminator which is able to distinguish between packet losses due to collisions/interference (e.g. hidden node) and weak signals (e.g. due to fading). The proposed algorithm has to be implemented (simulator and testbed) and evaluated. Requirements: Credits: Contact: | 
