Abstract: The intrinsic problems ofhidden/exposed terminal may bring about threat of conflict in inter-vehicular communication,and thus decrease network throughput.In this paper,we take the unidirectional feature of road into consideration,design single-channel transmission scheme for decreasing communication conflicts with position information and directional antenna,including the identification and notification of relative positions among adjacent nodes, the identification of node transmission state,and the method of directional transmission scheduling.By simulation experiments of inter-vehicular communication in NS-2,we verify that this scheme can discern the hidden/exposed terminal nodes and decrease conflicts effectively,and thus improve network performance.