車々聞方向指定ルーチングプロトコルDORPx

摘要

本研究室では，グループ車両間での道路情報の交換等を目的とした草々間通信方式の開発を進めている．これまでに，高速道路を想定した方向指定ルーチング（Direction Oriented Routing Protocol：DORP）［1］，市街地道路を想定した道路ゾーンと方向指定によるルーチング（DORP enhanced by zonal road：DORPz）［2］と交差点に固定中継器を用いた方向指定ルーチング（DORP collaborating with fixed relay points：DORPr）［3］を提案している．車々間通信では車両の移動により各端末の位置は激しく変化するが，前後関係はあまり変化しない．また，安全運転の支援・事故回避のために周辺車両と定期的に情報交換をしている．DORPx（DORP 全方式の総称）は，これらの特徴を積極的に利用している．本稿では，交差点を含む道路環境を想定し，DORPx の特性評価を行う．%We introduce three routing protocols adapting to inter-vehicle communications proposed in our laboratory. The first routing scheme named DORP ( Direction Oriented Routing Protocol ) that decides a direction of packet forwarding by using information of a beacon [1]. The second scheme named DORPz ( DORP enhanced by zonal road ) that enables an efficient packet routing at intersections by using zone information of roads [2]. The third scheme named DORPr ( DORP collaborating with fixed relay points ) that employs a packet relay point which memorizes the directions of vehicle movement by receiving beacons and gives routing information to the other vehicle terminals [3]. The position of each vehicle changes frequently by the movement in the road, but the anteroposterior relationship is hard to change. In addition, the vehicles generally exchange information with neighboring vehicles for the support of the safety driving by inter-vehicle communication. DORPx ( the generic term of all DORP schemes ) actively utilizes these characteristics. In this study, we evaluate DORPx in road environment including intersections.