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International audienceWe aim at dimensioning fixed broadband microwave wireless networks under unreliable channel conditions. As the transport capacity of microwave links is prone to variations due to, e.g., weather conditions, such a dimensioning requires special attention. It can be formulated as the determination of the minimum cost bandwidth assignment of the links in the network for which traffic requirements can be met with high probability, while taking into account that transport link capacities vary depending on channel conditions. The proposed optimization model represents a major step forward since we consider dynamic routing. Experimental results show that the resulting solutions can save up to 45% of the bandwidth cost compared to the case where a bandwidth over-provisioning policy is uniformly applied to all links in the network planning. Comparisons with previous work also show that we can solve much larger instances in significantly shorter computing times, with a comparable level of reliability

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We instigate the questions of: (i) whether increasing the number of available channels is always useful for improving the Quality of Service (QoS) (i.e., throughput or packet delivering delay) of Wireless Mesh Networks (WMNs), (ii) whether using more complex algorithms for managing Partially Overlapping Channels (POCs) is beneficial in terms of improving the QoS of WMNs?For the purpose of the instigation, we design a set of algorithms that can be combined to increase the spatial reuse and to schedule efficiently packet transmissions in WMNs. Extensive numerical experiments indicate that using POCs leads not only to a significant increase in network throughput as reported in previous studies, but also to a considerable decrease in average delay.

Faults in the GNSS measurements are the main reason for uncertainty positioning. Accuracy can thus be maximized by selecting only those observations least contaminated by faults to form the navigation solution (positioning) and discarding the rest. In this paper, we propose an algorithm to solve the problem of multi faults in the GNSS observations (pseudorange). The algorithm is based on observations projection on information space in order to detect and exclude the measurement faults and on Information Filter in order to estimate the position. The proposed method is tested using real data acquired with an experimental vehicle using low cost GNSS receiver in order to demonstrate its efficiency and its validity.

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