Feasibility analysis of UMTS handover logs for traffic state estimation

In this paper, we analyze the operational UMTS handover logs. The analysis result shows UMTS handover logs possessing more severe cell oscillation phenomenon compared to GSM. To eliminate the effect of cell oscillation phenomenon, we propose an approach to estimate the traffic state using UMTS handover logs. An experiment on a 12km road segment of Sun Yat-sen Freeway in Taiwan was conducted to verify the feasibility of our proposed approach. The experiment showed that every time a slowdown happened, a speed decreasing could be detected. Also, the estimation differences between the proposed approach and fix vehicle detection (VD) systems were less than 20kmph (km per hour) in 76% of the measurements, which proves that UMTS handover logs qualifies for traffic state estimation.