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In this paper, we account for radio-location experiments aiming at both indoor navigation and mobility detection applications for Wireless Body Area Networks (WBAN). This measurement campaign involved IEEE 802.15.4-compliant integrated radio devices organized within a full mesh topology over on-body and off-body links. The latter devices produce peerto-peer Received Signal Strength Indicators (RSSI) that could feed ranging, positioning or tracking algorithms. An in-depth behavioral analysis of the collected time-stamped radio-location metrics is thus proposed with respect to the captured human mobility (including body shadowing). Based on our observations and interpretations, practical insights are finally drawn in terms of system and algorithms design.

The interest for communications between vehicles and the infrastructure or other vehicles (V2X) has recently increased towards connected vehicle applications, and particularly cooperative collision avoidance (CoCA). In this paper, we evaluate the performance of LTE-V2X networks in the context of Intelligent Transportation Systems for traffic collision avoidance applications based on sharing occupancy maps between the infrastructure and the vehicles. We compare by simulation different LTE-V2X configurations under realistic conditions in an intersection scenario. Then, we evaluate every type of communication link (V2I and V2V) as a function of the density of vehicles. The results show the potential of the concept for V2X and the trade-offs in terms of reliability, capacity and latency.

International audienceWireless Body Area Networks (WBANs) have recently emer-ged as a solution to enable effective location-aware appli-cations. The rapid mobility of nodes is the most specific problem of this kind of networks and it is not well con-sidered when designing MAC protocols. In this paper, we consider a WBAN using a typical TDMA-based Medium Ac-cess Control (MAC) protocol and an Impulse Radio Ultra Wideband (IR-UWB) physical layer defined by the standard IEEE802.15.6. We investigate the impact of mobility on the Motion Capture applications. The Root Mean Square Er-ror (RMSE) of the estimated positions is analyzed according to different scheduling strategies at MAC layer under a real human mobility model. Our results show that an effective scheduling scheme leads to prioritize the own node position estimation. Finally, we propose to extend the study with a realistic human body channel

In the context of radiolocation in Wireless Body Area Networks (WBANs), nodes positions can be estimated through time-based ranging algorithms. For instance, the distance separating a couple of nodes can be estimated accurately by measuring the Round Trip Time of Flight of an Impulse Radio Ultra Wideband (IR-UWB) link. This measure usually relies on two or three messages transactions. Such exchanges take time and a rapid mobility of the nodes can reduce the ranging accuracy and consequently impact nodes localization process. In this paper, we quantify this localization error by confronting two broadcast-based optimized implementations of the three-way ranging algorithm with real mobility traces, acquired through a motion capture system. We then evaluate, in the same scenarios, the impact of the MAC-level scheduling of the packets within a TDMA frame localization accuracy. The results, obtained with the WSNet simulator, show that MAC scheduling can be utilized to mitigate the effect of nodes mobility.

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The purpose of this paper is to evaluate the impact of the node speed on the ranging estimation for location applications with Wireless Body Area Networks (WBAN). While estimated with the 3-Way ranging protocol (3-WR) , this distance between two nodes placed on the body can be affected by the human movements. Thus, we study theoretically the ranging error with the 3-WR, based on a perfect channel, a MAC layer based on TDMA using two scheduling strategies (Single node localization (P2P-B) and Aggregated & Broadcast (A&B)) and a PHY layer based on Ultra Wideband (IR-UWB). We demonstrate the accuracy of the model, and show that the distance error is highly correlated with the speed of nodes, while the associated mobility model has an impact on the design of MAC strategies by simulation.

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