VANETs Multipath Video Data Streaming Considering Road Features

Multipath video streaming in Vehicular Ad-hoc Networks (VANETs) is an evolving research topic. The adoption of video transmission in VANETs communication has become essential due to the comprehensiveness and applicability of video data for on-road advertisement and infotainment. Meanwhile, several research studies have considered how to apply and improve the transmission of the video quality. Due to this, the concurrent multipath transmission has been employed in order to achieve load balancing and path diversity, because of the high data rate of the video data.  However, the main nature of the road, which is the pathway for VANET nodes has not been considered explicitly. In this paper, the road features are considered for VANETs multipath video streaming based on the greedy geographical routing protocol. Thus, VANETs Multipath Video Streaming based on Road Features (VMVS-RF) protocol has been proposed. The protocol was compared with an ordinary Multipath Video Streaming (MVS). The result demonstrates that the proposed VMVS-RF protocol outperforms the MVS in terms of Data Receiving Rate (DRR), Structural Similarity (SSIM) index and Packet Loss Ratio (PLR)

Advances in Vehicular Ad-hoc Networks (VANETs): challenges and road-map for future development

Recent advances in wireless communication technologies and auto-mobile industry have triggered a significant research interest in the field of vehicular ad-hoc networks (VANETs) over the past few years. A vehicular network consists of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications supported by wireless access technologies such as IEEE 802.11p. This innovation in wireless communication has been envisaged to improve road safety and motor traffic efficiency in near future through the development of intelligent transportation system (ITS). Hence, governments, auto-mobile industries and academia are heavily partnering through several ongoing research projects to establish standards for VANETs. The typical set of VANET application areas, such as vehicle collision warning and traffic information dissemination have made VANET an interesting field of mobile wireless communication. This paper provides an overview on current research state, challenges, potentials of VANETs as well as the ways forward to achieving the long awaited ITS

隠れ端末問題及びフロー内干渉キャンセルを考慮したワイヤレスアドホックネットワークに関する研究

Performance of CSMA/CA (carrier sense multiple access/collision avoidance) wireless ad hoc network is severely affected by hidden terminal (HT) problem that results in the failure of carrier sense and causes the packet error due to collision. This thesis proposes a method of improving the performance of multi-hop ad hoc network by 4 steps which can be summarized as follows. First, the thesis analyzes HT effect on CSMA/CA unicast communication taking into account actual radio environments including both fading and capture effect. Based on the analysis results, it is predicted that multi-hop transmission is vulnerable to HT problem because of intra-flow interference (IFI). Regarding to this issue, as the second step, a CINR (carrier to interference and noise ratio) -based analysis method is proposed that can precisely estimate the packet delivery probability for CSMA/CA multi-hop transmission suffering from HT-caused IFI under fading environment. The results prove that conventional CSMA/CA media access control cannot achieve efficient multi-hop transmission. Therefore, as the third step, this thesis further proposes IFI-canceling multi-hop transmission (IFIC-MHT) scheme that enables efficient relaying with the highest traffic load for half-duplex multi-hop networks. The interference cancellation (IC) technique employs adaptive signal processing with a normalized least mean square (NLMS) algorithm for channel estimation and has good BER (bit error rate) and PER (packet error rate) performance under a wide range of SNR (signal to noise ratio) and SIR (signal to interference ratio) conditions. A multi-hop packet transmission frame format dedicated to the IFIC is designed. Finally, this thesis studies the effect of IFIC on large-scale ad hoc network where both intra-flow interference and inter-flow interference take place and together affect the multi-hop transmission.電気通信大学201