WAVE/DSRC 多車道自由電子收費系統之實作與驗證

Abstract

智慧型交通運輸系統(Intelligent Transportation System, ITS)能改善運輸系統、提升用路安全並提供各式各樣的商業服務。公速公路電子收費系統(Electronic Toll System, ETC)是ITS中重要的應用之一，多車道自由流電子收費系統為目前發展的趨勢。然而，傳統通訊技術如紅外線、RFID等皆不足以滿足多車道自由流系統對於通訊品質的需求。在本篇文章中，我們發展一WAVE/DSRC多車道自由流電子收費系統，將電子收費系統劃分成預約區及收費區，車輛進入預約區先使用控制頻道(control channel, CCH)向收費站請求服務頻道(service channel, SCH)，在進入收費區後使用該服務頻道與收費站進行交易。收費站中透過多個路邊節點分別使用不同的服務頻道，採用輪詢(polling)的方式對進入交易區的車輛進行免競爭(contention free)交易扣款程序。本篇文章使用Estinet7.0進行實驗模擬，結果顯示本系統相較於傳統電子收費系統能提供更可靠的服務品質，並藉由探討系統中不同參數設定所造成影響，提供開發者及實作人員做參考。

Intelligent Transportation System (ITS) provides efficient transport system and wide range of commercial applications. Highway Electronic Toll Collection (ETC) system is one of the most important applications in ITS. Multi-lane Free Flow (MLFF) ETC system is the trend of development in the world. However, traditional communication technologies, such as infrared and RFID, cannot satisfy the requirements in MLFF ETC systems. In this thesis, we develop a WAVE/DSRC contention free polling based ETC system. The toll area is divided into reservation zone and transaction zone. Vehicles entering reservation zone request toll gate for a reserved service channel on control channel. When vehicles entering transaction zone, they use reserved service channel to pay the tolls. The multiple roadside units (RSUs) with independent service channels in toll gate use polling based contention free transaction process to toll vehicles in transaction zone. We conduct experiments by Estinet7.0, the commercial version of NCTUns, and show the reliability of tolling service in our system. We also discuss effects of variable parameter setting and give some suggestions for further system developers.