Please wait a minute...
[an error occurred while processing this directive]

当期目录

    2016年 第14卷 第3期    刊出日期:2016-08-01
    Guest Editorial: Vehicular Communications, Networks, and Applications
    ZHUANG Weihua, ZHU Hongzi
    2016, 14(3):  1-2. 
    摘要 ( )   PDF (289KB) ( )  
    相关文章 | 多维度评价
    A vehicular ad hoc network (VANET) is a packet-switched network, consisting of mobile communication nodes mounted on vehicles, with very limited or no infrastructure support [1]. It supports communications among nearby vehicles, and between vehicles and nearby infrastructure/users, including vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-roadside unit (V2R), vehicle-to-pedestrian (V2P) communications, collectively referred to as vehicle-to-everything (V2X) communications [2]. The paradigm of VANETs will improve road safety, facilitate intelligent transportation, support infotainment, data sharing, and location based services, and will be a critical component in the future Internet of Things. The growing importance of vehicular communication networks has been recognized by governments, academia, and industry worldwide.

    The Federal Communications Commission in the United States has approved a radio spectral width of 75 MHz for Dedicated Short Range Communications (DSRC). Transport Canada supports the introduction of DSRC-based intelligent transportation applications in the frequency band 5850-5925 MHz. It is expected that the DSRC system will be the first wide-scale vehicular network in North America. The latest version of DSRC, IEEE 1609 Family of Standards for Wireless Access in Vehicular Environments (WAVE) [3] with IEEE 802.11p for channel access [4] has emerged for vehicular communications. In Europe, a car-to-car communication consortium has been initiated by European vehicle manufacturers, and is dedicated to further increase road traffic safety and efficiency by means of inter-vehicle communications [5]. The European Telecommunications Standards Institute (ETSI) has developed the intelligent transport systems (ITS) G5 standards for vehicular networks to operate on the 5 GHz radio frequency band [6], based on IEEE 802.11p physical and link layers. In Japan, the Association of Radio Industries and Businesses (ARIB) has issued the ARIB STD T-109 standard for vehicular communications using TV white space in the 700 MHz band [7]. In particular, the China Communications Standards Association (CCSA), together with the China telecom industry, has been actively participating in the 3GPP initiatives on LTE support for connected vehicles [8].

    VANETs provide a promising platform for future deployment of large scale and highly mobile network services. Given the automobile’s role as a critical component in our society, embedding Information and Communication Technology (ICT) services into automobiles has the potential to significantly improve our quality of life. This, along with great market demand for more reliability, safety, and entertainment value in automobiles, has led to many initiatives and support for deployment of vehicular networks and applications. The research and development activities for connecting vehicles via advanced communication and information technology have reached to a tipping point for significant impacts on society, economy, and daily life of ordinary people. Vehicular networks have unique networking characteristics, including highly dynamic network topology, distributed network control in peer-to-peer communications, and stringent service quality requirements for safety applications such as delay and packet delivery reliability. As a result, it provides both challenges and opportunities for further R&D activities in order to achieve reliable, secure, accurate, and fast end-to-end information delivery in VANETs.

    This special issue aims to present some recent research works for vehicular communication technology and its potential applications. It includes five technical contributions from leading researchers in vehicular communication networks. The first paper entitled “On Coexistence of Vehicular Overlay Network and H2H Terminals on PRACH in LTE” by Khan, Misic and Misic presents how to use the LTE physical random access channel (PRACH) to support vehicular machine-to-machine (VM2M) communications, and analyzes the impact of PRACH format and configuration parameters on the performance of VM2M subnetworks. The second paper is entitled “A Cooperative Forwarding Scheme for VANET Routing Protocols” by WU, JI, and YOSHINAGA. It focuses on how to improve the end-to-end packet delivery ratio in unicast routing protocols via multiple forwarding nodes and network coding. Numerical results demonstrate that the proposed strategies can improve the packet delivery ratio without increasing message overhead. The third paper, co-authored by HE and CAI, studies hybrid content distribution framework for large-scale vehicular ad hoc networks. It introduces a hybrid network solution to address scalability issue of content distribution in large-scale vehicular ad hoc networks. An overlay store-carry-and-forward content distribution network is established to model a large-scale VANET, and utility-based optimization is formulated to find optimal data packet routing solutions. The next paper, co-authored by YANG, ZHENG, LEI, and XIANG, is entitled “Heterogeneous Vehicular Networks for Social Networks: Requirements and Challenges”. It presents two social network architectures that embed social characteristics into heterogeneous vehicular networks. It discusses several use cases to analyze service requirements and associated challenges. The last (but not least) paper “A Cloud Computing Perspective for Distributed Routing in Vehicular Environments” is co-authored by Shivshankar and Jamalipour. It presents how to effectively apply cloud computing to address challenges of the spatio-temporal multicast (SMRP) distributed routing in VANETs. It proposes a new mechanism to exploit cloud computing in the routing process, which can increase service discovery rate and reduce the required resource and service discovery download time with roadside units and internet, in comparison with the vehicular clouds obtained directly through the SMRP based routing.

    We would like to thank all the authors for choosing this special issue to publish their new research results, all the reviewers for their meticulous review comments and suggestions which help to improve the technical quality and presentation of this special issue, and the editorial official of ZTE Communications for all the support and help during the editorial process of this special issue. We hope that our readers will enjoy reading the articles and find this special issue helpful to their own research work. Working together, we will make connected vehicles and Internet of vehicles a reality in the near future.
    On Coexistence of Vehicular Overlay Network and H2H Terminals on PRACH in LTE
    Nargis Khan, Jelena Mišić, and Vojislav B. Mišić
    2016, 14(3):  3-12.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.001
    摘要 ( )   PDF (537KB) ( )  
    相关文章 | 多维度评价
    Vehicular ad hoc networks (VANETs) that use the IEEE 802.11p communication standard face a number of challenges, not least when it comes to safety messages on the VANET control channel (CCH) where short delay times and reliable delivery are of primary importance. In this paper we propose a vehicular machine-to-machine (VM2M) overlay network that uses Long Term Evolution (LTE) physical random access channel (PRACH) to emulate VANET CCH. The overlay network uses dedicated preambles to separate vehicular traffic from regular LTE traffic and a carrier sense multiple access with collision avoidance (CSMA-CA) layer similar to the one used in IEEE 802.15.4 to avoid the four step handshake and the overhead it incurs. The performance of the proposed overlay is evaluated under a wide range of PRACH parameters which conform to the scenarios with high vehicle velocities and large distances between roadside units (RSUs) that may be encountered in rural areas and on highways.
    A Cooperative Forwarding Scheme for VANET Routing Protocols
    WU Celimuge1, JI Yusheng 2, and YOSHINAGA Tsutomu1
    2016, 14(3):  13-21.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.002
    摘要 ( )   PDF (1816KB) ( )  
    相关文章 | 多维度评价
    Providing efficient packet delivery in vehicular ad hoc networks (VANETs) is particularly challenging due to the vehicle movement and lossy wireless channels. A data packet can be lost at a forwarding node even when a proper node is selected as the forwarding node. In this paper, we propose a loss-tolerant scheme for unicast routing protocols in VANETs. The proposed scheme employs multiple forwarding nodes to improve the packet reception ratio at the forwarding nodes. The scheme uses network coding to reduce the number of required transmissions, resulting in a significant improvement in end-to-end packet delivery ratio with low message overhead. The effectiveness of the proposed scheme is evaluated by using both theoretical analysis and computer simulations.
    Hybrid Content Distribution Framework for Large-Scale Vehicular Ad Hoc Networks
    HE Jianping and CAI Lin
    2016, 14(3):  22-28.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.003
    摘要 ( )   PDF (1658KB) ( )  
    相关文章 | 多维度评价
    Content distribution in large-scale vehicular ad hoc networks is difficult due to the scalability issue. A message may need to be carried by several vehicles till it reaches the destination. To select an appropriate next-hop carrier, the current carrier should exchange control messages with a large number of vehicles encountered, and thus the pure ad hoc solution is not scalable. In this paper, we introduce a hybrid-network solution. We first divide the area into regions, and select a hot spot in each region to install a road-side unit (RSU). RSUs can coordinate message exchanges between vehicles, and storage devices are used to temporarily hold a message waiting for the next-hop carrier. The RSUs and the vehicles traveling between them construct an overlay store-carry-and-forward content distribution network. Two types of vehicles exist, one with fixed mobility patterns such as buses, and the other with random patterns such as taxis. Considering one or both types of vehicles, utility-based optimization problems can be formulated to find the optimal routing solutions. Using the bus and taxi traces of Shanghai city, we demonstrate the effectiveness of the hybrid framework in terms of delivery delay, delivery ratio and overhead ratio.
    Heterogeneous Vehicular Networks for Social Networks: Requirements and Challenges
    YANG Haojun, ZHENG Kan, LEI Lei, and XIANG Wei
    2016, 14(3):  29-35.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.004
    摘要 ( )   PDF (1317KB) ( )  
    相关文章 | 多维度评价
    Heterogeneous vehicular networks (HetVNETs) are regarded as a promising technique for meeting various requirements of intelligent transportation system (ITS) services. With the rapid development of mobile Internet in the past decade, social networks (SNs) have become an indispensable part of human life. Based on this indivisible relationship between vehicles and users, social characteristics and human behaviors can significantly affect vehicular network performance. Hence, we firstly present two architectures for SNs by introducing social characteristics into the HetVNETs. Then, several user cases are also given in this paper, in which service requirements are analyzed simultaneously. At last, we briefly discuss potential challenges raised by the HetVNETs for SNs.
    A Cloud Computing Perspective for Distributed Routing in Vehicular Environments
    Smitha Shivshankar and Abbas Jamalipour
    2016, 14(3):  36-44.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.005
    摘要 ( )   PDF (1153KB) ( )  
    相关文章 | 多维度评价
    Vehicular networks have been envisioned to provide us with numerous interesting services such as dissemination of real-time safety warnings and commercial advertisements via car-to-car communication. However, efficient routing is a research challenge due to the highly dynamic nature of these networks. Nevertheless, the availability of connections imposes additional constraint. Our earlier works in the area of efficient dissemination integrates the advantages of middleware operations with multicast routing to design a framework for distributed routing in vehicular networks. Cloud computing makes use of pools of physical computing resources to meet the requirements of such highly dynamic networks. The proposed solution in this paper applies the principles of cloud computing to our existing framework. The routing protocol works at the network layer for the formation of clouds in specific geographic regions. Simulation results present the efficiency of the model in terms of service discovery, download time and the queuing delay at the controller nodes.
    Towards Practical Implementation of Data and Energy Integrated Networks
    HU Jie, ZHANG Yitian, YU Qin, and YANG Kun
    2016, 14(3):  45-54.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.006
    摘要 ( )   PDF (1279KB) ( )  
    相关文章 | 多维度评价
    With the rapid development of the mobile internet and the massive deployment of the Internet of Things, mobile devices, including both the consumer electronics and the sensors, become hungrier for the energy than ever before. Conventional cable based charging largely restrict the movement of the mobile devices. Wireless charging hence emerges as an essential technique for enabling our ultimate goal of charging anytime and anywhere. By efficiently exploiting the legacy of the existing communication infrastructure, we propose a novel data and energy integrated network (DEIN) in order to realise the radio frequency (RF) based wireless charging without degrading the information transmission. In this treatise, we focus on the implementation of the DEIN in both the theoretical and practical aspects, concerning the transceiver architecture design and the rectifier circuit design. Furthermore, we also present a Wi-Fi based testbed for demonstrating the availability of the RF based wireless charging.
    Light Field Virtual View Rendering Based on EPI-Representations
    SUN Yule and YU Lu
    2016, 14(3):  55-59.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.007
    摘要 ( )   PDF (1378KB) ( )  
    相关文章 | 多维度评价
    Image-Based Rendering (IBR) is one powerful approach for generating virtual views. It can provide convincing animations without an explicit geometric representation. In this paper, several implementations of light field rendering are summarized from prior arts. Several characteristics, such as the regular pattern in Epipolar Plane Images (EPIs), of light field are explored with detail under 1D parallel camera arrangement. It is proved that it is quite efficient to synthesize virtual views for Super Multi-View (SMV) application, which is in the third phase of Free - Viewpoint Television (FTV). In comparison with convolutional stereo matching method, in which the intermediate view is synthesized by the two adjacent views, light field rendering makes use of more views supplied to get the high-quality views.
    An Efficient Scheme of Detecting Repackaged Android Applications
    QIN Zhongyuan, PAN Wanpeng, XU Ying, FENG Kerong, and YANG Zhongyun
    2016, 14(3):  60-66.  doi:DOI:10.3969/j.issn.1673-5188.2016.03.008
    摘要 ( )   PDF (1465KB) ( )  
    相关文章 | 多维度评价
    The increasing popularity of Android devices gives birth to a large amount of feature-rich applications (or apps) in various Android markets. Since adversaries can easily repackage malicious code into benign apps and spread them, it is urgent to detect the repackaged apps to maintain healthy Android markets. In this paper we propose an efficient detection scheme based on twice context triggered piecewise hash (T-CTPH), in which CTPH process is called twice so as to generate two fingerprints for each app to detect the repackaged Android applications. We also optimize the similarity calculation algorithm to improve the matching efficiency. Experimental results show that there are about 5% repackaged apps in pre-collected 6438 samples of 4 different types. The proposed scheme improves the detection accuracy of the repackaged apps and has positive and practical significance for the ecological system of the Android markets.
    The whole issue of ZTE Communications August 2016, Vol. 14 No. 3
    2016, 14(3):  0. 
    摘要 ( )   PDF (2481KB) ( )  
    相关文章 | 多维度评价