Fig. 8From: Trajectory estimation based on mobile network operator data for cellular network simulationsTrajectory 1. Estimation of event positions based on different coverage prediction methods: Coverage prediction (top left), coverage prediction including height and building model (top right) and Voronoi tessellation (bottom left). The last picture shows the original trajectory recorded using a GPS tracker (black) and the estimated trajectory based on event positions derived from the top right image (green). The purple points indicate an active speech session, the blue ones a data session, respectively. The yellow points are the actual event positions which have been recorded using a handsetBack to article page