NTCIP通訊網路績效評估之研究

Abstract

結合了資訊、通訊、控制與運輸的專業知識而成的智慧型運輸系統已經成為現今解決交通問題的趨勢。透過智慧型運輸系統的運作，交通管理單位能掌握人、車、路三者間的即時資訊，而即時資訊的溝通傳播則需透過NTCIP通訊協定的運作方能成功。 本研究之目的為參考資料通訊網路運作架構及分散式交通控制系統架構，提出一個通訊網路模擬模式，用以衡量在不同交通狀況下，採用NTCIP當作通訊網路架構時該通訊網路系統之績效，其中包含了三大子系統下的終端設備傳輸需求，ATMS—偵測器、號誌化路口，ATIS—可變資訊標誌，及APTS—智慧型站牌；並且根據實際交通狀況，將模擬環境區分為尖峰小時與非尖峰小時，單一控制中心與三控制中心，利用系統平均延滯時間與系統平均等候列長度兩項來探討不同環境的系統績效。 由數值實驗結果得知，本研究所提出之模擬模式具有合理性，根據模擬之數值樣本的迴歸分析顯示，本模式具有良好之解釋能力，在非尖峰小時與三控制中心的情況下更為良好，可用來預測與分析建置NTCIP-based通訊網路時的系統績效，所獲得之結果亦具有相當的參考價值。

NTCIP plays an important role to communicate the real-time information of people, vehicles and roads. Therefore, how to evaluate the performance of NTCIP-based communication network is a serious problem. This thesis proposes a simulation model which refers to the data communication network architecture and distributed traffic control system architecture, as the evaluating approach. In numerical experiments, we consider the real traffic transmission requirements and take system average delay and queue length as the performance evaluation indices. The results show that our model is reasonable. The regression analysis of experimental statistics presents our model with well-explaining ability to interpret the relationship between performance evaluation indices and queue server processing time. It means that the model we proposed can be as a significant reference when constructing the NTCIP-based communication network.