Conventional Vehicular Ad-hoc Network Research Articles

도심 교차로에서 효율적 경로 관리를 위한 자동차 통신용 라우팅 알고리즘

본 논문에서는 도심 교차로에서 경로 이탈 확률을 낮추어 줄 수 있는 차량 통신용 라우팅 알고리즘을 제안한다. 차량이 밀집된 도심의 교차로 지역에서는 차량들의 방향 전환으로 잦은 네트워크 단절과 패킷 전송지연 문제를 발생 시킬 수 있다. 본 논문에서는 이러한 문제점을 개선하기 위해 전송 노드 선정 과정에서 같은 진행방향의 노드를 이웃 노드로 선정하여 교차로에서 네트워크 단절의 비율을 낮출 수 있는 VANET (Vehicular Ad-hoc Network)용 라우팅 알고리즘을 제안한다. 시뮬레이션을 통한 성능분석 결과는 제안하는 알고리즘이 기존 라우팅 알고리즘에 비해 도심 교차로에서 경로 이탈 확률을 약 10% 감소시키며 네트워크 단절 비율을 5% 감소시킴을 보인다. This paper proposes a vehicle ad-hoc network (VANET) routing algorithm to reduce the probability of routing path discontinuity in urban intersections. In urban intersections, the vehicles may frequently change their moving directions. It can cause the disconnection of routing path and the increase of a packet transmission delay. In order to resolve this problem, the proposed routing algorithm exploits the information of moving directions in urban intersections. In this way, the proposed algorithm can reduce the probability of the local maximum which causes the increase of the number of routing hops and packet transmission delay. Simulation results show that the proposed algorithm can reduce the local maximum probability by 10% and increase the successful packet transmission ratio by 5% compared to the conventional VANET routing algorithms.

Communication framework for vehicle ad hoc network on freeways

Providing an efficient and stable communication framework of Vehicular Ad hoc Network (VANET) is an emerging issue. Most of conventional VANET communication schemes only support short range transmission, vehicles need to relay traffic data or frequently switch to different roadside units. Such an ad hoc-based method suffers a high jitter delay and makes it difficult to develop travel and real-time multimedia services, such as traffic information dissemination and fleet management. Fortunately, existing novel wireless technologies, e.g. WiMAX mobile multi-relay (MMR), provide long transmission range and high transmission rate in mobile environments. This study presents a Safety/Vehicular Information Delivery (SVID) framework, an application-layer VANET communication protocol. A power-abundant, large size vehicle, called SIP-based relay vehicle (SRV), e.g. long distance transportation bus, plays as a relay station (RS) providing the connectivity to other small vehicles around it. To provide VANET services in SVID, this work adopts a SIP-based mechanism. The proposed scheme can provide more efficient communication than conventional VANET ad hoc mode. Simulation results show that the proposed scheme achieves a low SIP transaction time, jitter delay, frame loss rate while avoiding the broadcast storm problem.