  In this work, we face the issue of achieving an efficient dynamic mapping in
vehicular networking scenarios, i.e., to obtain an accurate estimate of the
positions and trajectories of connected vehicles in a certain area. State of
the art solutions are based on the periodic broadcasting of the position
information of the network nodes, with an inter-transmission period set by a
congestion control scheme. However, the movements and maneuvers of vehicles can
often be erratic, making transmitted data inaccurate or downright misleading.
To address this problem, we propose to adopt a dynamic transmission scheme
based on the actual positioning error, sending new data when the estimate
passes a preset error threshold. Furthermore, the proposed method adapts the
error threshold to the operational context according to a congestion control
algorithm that limits the collision probability among broadcast packet
transmissions. This threshold-based strategy can reduce the network load by
avoiding the transmission of redundant messages, and is shown to improve the
overall positioning accuracy by more than 20% in realistic urban scenarios.
