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Effect of Packet Loss and Delay on V2X Data Fusion
Tzu-Kuang Lee,Jen-Jee Chen,Yu-Chee Tseng,Cheng-Kuan Lin 한국통신학회 2020 한국통신학회 APNOMS Vol.2020 No.09
Sensing data fusion is one of the most important technologies in autonomous driving. Its performance depends on advance communication technology. Cellular-Vehicle to Everything (C-V2X) initially defined as LTE V2X in 3GPP Release 14 is a solution for vehicle communication that includes Vehicle-to- Infrastructure (V2I), Vehicle-to-person (V2P), and Vehicle-to- Vehicle (V2V). Although 4G LTE and 5G provides high-speed transmission, packet loss and delay are still inevitable. Packet loss and delay affect the safety of autonomous driving, especially for the judgment of emergency. In this paper, we compare the accuracy of data fusion under different rate of packet loss and broadcast frequency on the simulated platform CALAR. And we propose a skill to improve accuracy. Experiments show that the proposed skill significantly alleviates the effect of communication packet loss and delay on the accuracy of V2X data fusion.
System Study of the Wireless Multimedia Ad-hoc Network based on IEEE 802.11g
Chung-Wei Lee,Jonathan C.L. Liu,Kun Chen,Yu-Chee Tseng,S.P. Kuo 보안공학연구지원센터 2008 International Journal of Security and Its Applicat Vol.2 No.2
The construction of a wireless multimedia ad-hoc network needs to go across the mixed environment with the indoor, the wall-penetration, and the outdoor condition. This paper presents our contribution to address the system design aspects of a multimedia-enabled network based on IEEE 802.11g ad-hoc mode. There are distinct differences between indoor and outdoor environment and penetrating the walls stressed the system limit of the 802.11g ad-hoc mode. Therefore, routing decisions should be made intelligently with the environmental respect to maximize the bandwidth support on the end-to-end paths. By investigating the experimental results of the average throughput with the 802.11g adhoc mode, we have collected the different performance characteristics among the indoor, the wall-penetration and the outdoor environment. Via the experiments and analyses, we have observed that the ad-hoc mode had the worst performance within 5 meters in indoor environments. In outdoor environments, TCP seemed to favor either short distance (e.g., 5 meters) or long distance (e.g., 25 meters). On the other hand, the best performance UDP has achieved with the distance of 10 meters. When the wall-enetration occurs, it is important that the routing nodes in the building edge areas are placed close-by within 5 meters. Given the solid evidences from the baseline experiments, we have embedded the heuristic algorithms into the routing decisions. We have thus simulated a large area of 300 meters by 300 meters with hundreds of routing nodes. After investigating over 100 (randomlygenerated) topology scenarios, the performance results indicate that our proposed scheme produces the higher-bandwidth paths for most of the cases. Even in the less-dense cases, our proposed schemes still can find the better paths with bandwidth about 30% higher than the conventional methods.