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Item type:Publication, Access status: without files , Analytical Model for Aircraft-to-Aircraft Link Probability over the North Atlantic CorridorAircraft Ad-hoc Networks (AANETs) are capable not only to allow low-latency Internet connectivity on aircraft but also to transmit safety-critical data. An aircraft in distress could transmit important information to another nearby aircraft in range before it crashes on the ground. In this paper the link probability for aircraft crossing the North Atlantic Corridor is investigated. An analytical model for the nearest neighbor distribution is proposed taking the shape and dynamic position of North Atlantic flight corridors into account. A uniform distribution of nodes is assumed in a bounded model area. Simulation results and empirical aircraft position data captured over 10 weeks are analyzed and used for verification of the analytical model. The link probability is derived from the nearest neighbor distribution and the model performance is evaluated. Aircraft sticking to North Atlantic flight tracks bias the assumed uniform distribution over the area. Therefore the results differ for east-and westbound flights. A link probability of more than 99% can be achieved if the communication range is greater than 250km and at least 40 aircraft are located within the model area. The average error of the model predicting the required communication range for a 99% link probability amounts to 8.94%.Publicationtype: Conference Paper287 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Extending On-the-fly Network Coding by Interleaving for Avionic Satellite LinksStill today, aircraft disappear and crash without communicating their last position. Looking into details, satellite communications currently seems to be the only reliable way to connect and send data on long-distance flights. However, geostationary satellite systems suffer from high propagation delays making Forward Error Correction (FEC) schemes beneficial compared to error handling by retransmissions. In this paper, Random Linear Network Coding (RLNC) is proposed as a packet level FEC technique for high delay satellite communication. Using emulation, it is shown that correlated losses typical for a satellite channel result in a high variation in the number of redundant symbols required to decode a generation. This can be improved by using interleaving, which comes by the cost of an increased delay. A novel approach is introduced that combines On-the-fly Coding and interleaving. This can significantly reduce the average delay introduced by interleaving and allows to efficiently overcome correlated losses in combination with Network Coding for time-critical applications.Publicationtype: Conference Paper462