We developed UAVNet, a framework for the autonomous deployment of a flying Wireless Mesh Network using small quadrocopter-based Unmanned Aerial Vehicles (UAVs). The flying wireless mesh nodes are automatically interconnected to each other and building an IEEE 802.11s wireless mesh network. The implemented UAVNet prototype is able to autonomously interconnect two end systems by setting up an airborne relay, consisting of one or several flying wireless mesh nodes. The developed software includes basic functionality to control the UAVs and to setup, deploy, manage, and monitor a wireless mesh network. Our evaluations have shown that UAVNet can significantly improve network performance.

Virtual testbeds model them by seamlessly integrating physical, simulated, and emulated sensor nodes and radios in real time

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Low latency for packet delivery, high throughput, good reactivity, and energy-efficient operation are key challenges that MAC protocols for Wireless Sensor Networks (WSNs) have to meet. Since traffic patterns as well as network load may change during network lifetime, adaptability of the protocol stack, e.g. in terms of duty cycling, and the integration of reliable transport mechanisms are mandatory. So far, given that optimizations for energy-efficiency and performance parameters are contradicting, most MAC protocols proposed have concentrated on either one or the other. In order to close this gap, we designed BEAM (Burst-aware Energy-efficient Adaptive MAC). BEAM uses a new adaptive duty cycle mechanism, which reacts quickly to changing traffic loads and traffic patterns. The integration of explicit acknowledgments allows for supporting hop-to-hop reliability, lowering the overall energy expenditures of the network for end-to-end transmissions. The protocol itself is IEEE 802.15.4 conform and can easily be used for energy-efficient TCPIIP networking. As a result, BEAM performs well in entirely different environments and application scenarios, making it an all-purpose MAC protocol for WSNs.

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In the past five years, many energy-efficient medium access protocols for all kinds of wireless networks (WSNs) have been proposed. Some recently developed protocols focus on sensor networks with low traffic requirements are based on so-called preamble sampling or lowpower listening. The WiseMAC protocol is one of the first of this kind and still is one of the most energy-efficient MAC protocols for WSNs with low or varying traffic requirements. However, the high energy-efficiency of WiseMAC has shown to come at the cost of a very limited maximum throughput.In this paper, we evaluate the properties and characteristics of a WiseMAC implementation in simulation and on real sensor hardware. We investigate on the energyconsumption of the prototype using state-of-the-art evaluation methodologies. We further propose and examine an enhancement of the protocol designed to improve the trafficadaptivity of WiseMAC. By conducting both simulation and real-world experiments, we show that the WiseMAC extension achieves a higher maximum throughput at a slightly increased energy cost both in simulation and real-world experiments.

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