一個運用行動網路之換手與通話到達為分析基礎的車輛速度估計機制

Abstract

資訊科技和通訊科技提升了智慧型運輸系統（Intelligent Transportation System, ITS）的品質。相較於以道路上的車輛偵測裝置（Stationary Vehicle Detectors, SVDs）或全球衛星定位系統（Global Position System, GPS）為基礎取得交通資訊等傳統方式，利用流動車輛上的手機訊號資料（Cellular Floating Vehicle Data, CFVD）來推測交通狀況將會更為簡便、且更具成本效益。本研究提出一種新的方法來評估通話到達（Call Arrival）、換手（Handover）與交通流量、交通密度之間的關聯，再利用這些關聯性估計出交通速度。透過數值分析，我們探討交通資訊和行動通訊行為對通話到達與換手的影響；在模擬實驗中，我們以本研究所提出的方法估計出流量、密度、速度等交通資訊，並將估計結果與實際交通資訊比較。結果顯示一般情況下行車速度之估計值的準確率是89.75%，而在交通壅塞的情況下行車速度之估計值的準確率是89.15%。因此，本研究所提之方法可以有效地為智慧型運輸系統提供交通資訊。

Information and communication technologies have improved the quality of Intelligent Transportation Systems (ITS). The real-time traffic information has traditionally been collected via stationary vehicle detectors (SVDs) or GPS-based probe cars. Compared to the traditional ways, estimating traffic information from Cellular Floating Vehicle Data (CFVD) is more cost-effective, and easier to acquire. In this paper, we propose a novel approach to evaluate the relation of call arrival, handover, traffic flow, and traffic density. Moreover, the traffic speed is estimated by the proposed approach according to CFVD. Through the analytical analysis, we study the effects of traffic information (e.g. traffic flow and vehicle speed) and communication behaviors (e.g. call arrival rate and call holding time) on handovers and call arrivals. In the simulation, we compare the estimated traffic information with the real traffic information. The experiment results show that the accuracy of traffic speed estimation is 89.75%. Furthermore, in the case of traffic congestion, the accuracy of traffic speed estimation is 89.15%. Therefore, the proposed approach can be used to estimate traffic speed from CFVD for ITS.