scholarly journals Adaptive Beaconing in Mobility Aware Clustering Based MAC Protocol for Safety Message Dissemination in VANET

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Nishu Gupta ◽  
Arun Prakash ◽  
Rajeev Tripathi
Keyword(s):  
Ad Hoc ◽  
Mac Protocol ◽  
Ieee 802.11P ◽  
Bandwidth Utilization ◽  
Transmission Frequency ◽  
Vehicle Communication ◽  
Safety Message ◽  
Vehicle To Vehicle ◽  
Wide Range

Majority of research contributions in wireless access in vehicular environment (WAVE)/IEEE 802.11p standard focus on life critical safety-related applications. These applications require regular status update of vehicle’s position referred to as beaconing. Periodic beaconing in vehicle to vehicle communication leads to severe network congestion in the communication channel. The condition worsens under high vehicular density where it impacts reliability and upper bound latency of safety messages. In this paper, WAVE compliant enhancement to the existing IEEE 802.11p protocol is presented which targets prioritized delivery of safety messages while simultaneously provisioning the dissemination of nonsafety messages. Proposed scheme relies on dynamic generation of beacons to mitigate channel congestion and inefficient bandwidth utilization by reducing transmission frequency of beacons. Through the use of clustering mechanism, different beaconing frequencies and different data transmission rates are assigned to prioritize vehicular mobility. Through extensive simulation results, the performance of the proposed approach is evaluated in terms of a wide range of quality of service (QoS) parameters for two different transmission ranges. Results show that the proposed protocol provides significant enhancement and stability of the clustered topology in vehicular ad hoc network over existing standard and other protocols with similar applications.

scholarly journals A hybrid access method for broadcasting of safety messages in IEEE 802.11p VANETs

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Xiaoying Lei ◽  
Xiangjin Chen ◽  
Seung Hyong Rhee
Keyword(s):  
Access Control ◽  
Multiple Access ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Ieee 802.11P ◽  
Media Access Control ◽  
Access Method ◽  
Safety Message ◽  
Hybrid Access

AbstractVehicular Ad-hoc Networks (VANETs) can improve the road safety by transmitting safety-critical messages such as beacons and emergency messages. IEEE 802.11p VANETs have adopted the carrier sense multiple access with collision avoidance (CSMA/CA) mechanism for the multiple access control. The 802.11p media access control (MAC) protocol, however, can not guarantee the reliability of broadcasting data, since the reception of transmitted messages are not acknowledged. Moreover, the backoff scheme of the 802.11p MAC utilizes a fixed-size contention window for safety message broadcasting, which causes high collision probabilities especially in dense environments. In order to improve such drawbacks, we propose a hybrid access method as follows: Nodes are equipped to reserve time slots for the next round of broadcasting, while unoccupied time slots are preserved for those which have emergency needs. In addition, implicit feedbacks are enabled for detecting collisions incurred during random channel accesses in preserved time slots. We devise a mathematical model which optimally controls the parameters of our scheme while minimizes the cost caused by idle channels and collisions. Extensive simulations show that our mechanism can remarkably improve the performance of VANETs in broadcasting of the safety messages.

scholarly journals Feasibility Analysis of Vehicle-to-vehicle Communication on Suburban Road

2013 ◽  
Vol 25 (5) ◽  
pp. 483-493 ◽  
Author(s):  
Luoyi HUANG ◽  
Jiao YAO ◽  
Wei WU ◽  
Xiaoguang YANG
Keyword(s):  
Communication System ◽  
High Speed ◽  
Communication Technologies ◽  
Ieee 802.11P ◽  
Received Signal Strength Indicator ◽  
Vehicle Communication ◽  
Dedicated Short Range Communications ◽  
Related Information ◽  
Vehicle To Vehicle ◽  
Vehicle To Vehicle Communication

With the evolution of advanced wireless communication technologies, tremendous efforts have been invested in vehicular networking, particularly the construction of a vehicle-to-vehicle communication system that supports high speed and mobility. In vehicle-to-vehicle communication environment, vehicles constantly exchange information using wireless technology. This paper aims to propose a vehicle-to-vehicle communication system and validate the feasibility of the system on a suburban road in China. Two vehicles were used equipped with IEEE 802.11p based DSRC (Dedicated Short Range Communications) device to construct a vehicle-to-vehicle communication platform. The system architecture consisting of hardware and software was described in details. Then, communication characteristics such as RSSI (Received Signal Strength Indicator), latency and PLR (packet loss rate) were analyzed. Additionally, GPS-related information (such as ground speed and location) was obtained through field test on a suburban road in Shanghai and Taicang City. The test results demonstrate satisfactory performance of the proposed system.

scholarly journals Enhancing V2X Communication Based on a New Comb-Pilot Estimation Approach

2016 ◽  
Vol 2016 ◽  
pp. 1-14
Author(s):  
Aymen Sassi ◽  
Yassin El Hillali ◽  
Atika Revenq ◽  
Faiza Charfi ◽  
Lotfi Kamoun
Keyword(s):  
Performance Evaluation ◽  
Communication Systems ◽  
Orthogonal Frequency Division Multiplexing ◽  
Performance Enhancement ◽  
Human Life ◽  
Ieee 802.11P ◽  
Vehicle To Vehicle ◽  
Pilot Symbols ◽  
Quality Of Transmission

Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I) communication systems, known as V2X technologies, have increasingly attracted attention in current research on road safety and traffic ergonomics. The performance evaluation of these communication systems is an important step before their potential integration and use in real systems. V2X communications are based on the IEEE 802.11p standard also known as Wireless Access in Vehicular Environment (WAVE). V2X can affect human life; therefore a deep study related to V2X performance evaluation should be done in order to be sure about the system reliability. In this context, we have elaborated a deep study related to the effect of transmission range on V2X communications by considering the terminal mobility. First, we have evaluated the performance of the PHY layer on the IEEE 802.11p using simulation. Secondly, we have conducted real case measurements using the Arada LocoMate Transmission system. The obtained results shows the necessity to optimize the quality of transmission in V2X communications. Consequently, we propose in this paper a new comb-pilot technique to enhance the quality of Orthogonal Frequency Division Multiplexing (OFDM) transmission. Our proposal consists in two new uses of the pilot subcarrier estimation technique in order to decrease the elevated bit error rate (BER). The quality of transmission (QoT) is first evaluated relating to the pilot symbol rearranged positions. Second, we proposed to optimize the QoT by adding two supplementary pilot symbols as it can offer better channel estimation results. Based on the performance evaluation of our proposal, it is confirmed that both of rearrangement and the adding of the pilot patterns lead to performance enhancement compared to baseline model (standardized one).

Potential Using Vehicle to Vehicle Communication Based on Wireless Fidelity (Wi-Fi) for Supporting Intelligent Transportation Systems (ITS)

2021 ◽  
pp. 61-76
Author(s):  
إسراء عصام بن موسى ◽  
عبدالسلام صالح الراشدي
Keyword(s):  
Intelligent Transportation Systems ◽  
Ad Hoc ◽  
Real Life ◽  
Intelligent Transportation ◽  
Transportation Systems ◽  
The Road ◽  
Vehicle Communication ◽  
Vehicle To Vehicle ◽  
Vehicle To Vehicle Communication ◽  
Wireless Fidelity

Vehicular Ad-hoc Network (VANET) becomes one of the most popular modern technologies these days, due to its contribution to the development and modernization of Intelligent Transportation Systems (ITS). The primary goal of these networks is to provide safety and comfort for drivers and passengers in roads. There are many types of VANET that are used in ITS, in this paper, we particularly focus on the Vehicle to Vehicle communication (V2V), which each vehicle can exchange information to inform drivers of other vehicles about the current state of the road flow, in the event of any emergency to avoid accidents, and reduce congestion on roads. We proposed V2V using Wi-Fi (wireless fidelity); the reason of its unique characteristics that distinguish it from other types. There are many difficulties and the challenges in implementing most types of V2V, and the reason is due to the lack of devices and equipment needed for real implementation. To prove the possibility of applying this type in real life, we made a prototype contains a modified toy car, a 12-volt power supply, sensors, visual, audible alarm, a visual “LED” devices, and finally a 12-volt DC relay unit. As a conclusion, the proposed implementation in spite of minimal requirements and use simple equipment, we have achieved the most important main objectives of the paper: preventing vehicles from collision, early warning, and avoiding congestion on the roads.

Medium Access Protocols for Cooperative Collision Avoidance in Vehicular Ad-Hoc Networks

2013 ◽  
pp. 354-375
Author(s):  
Md. Imrul Hassan ◽  
Hai L. Vu ◽  
Taka Sakurai
Keyword(s):  
Collision Avoidance ◽  
Road Safety ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Dynamic Networks ◽  
Medium Access ◽  
Vehicle To Vehicle ◽  
Hoc Networks ◽  
Safety Applications

It is envisaged that supporting vehicle-to-vehicle and vehicle-to-infrastructure communications with a Vehicular Ad-Hoc Network (VANET) can improve road safety and increase transportation efficiency. Among the candidate applications of VANETs, cooperative collision avoidance (CCA) has attracted considerable interest as it can significantly improve road safety. Due to the ad hoc nature of these highly dynamic networks, no central coordination or handshaking protocol can be assumed and safety applications must broadcast information of interest to many surrounding cars by sharing a single channel in a distributed manner. This gives rise to one of the key challenges in vehicle-to-vehicle communication systems, namely, the development of an efficient and reliable medium access control (MAC) protocol for CCA. In this chapter, we provide an overview of proposed MAC protocols for VANETs and describe current standardization activities. We then focus on the performance of the IEEE 802.11 carrier sense multiple access (CSMA) based MAC protocol that is being standardized by the IEEE standards body for VANET applications. In particular, we review prominent existing analytical models and study their advantages, disadvantages and their suitability for performance evaluation of the MAC protocol for VANETs. After a discussion of the shortcomings of these models, we develop a new analytical model in the second half of the chapter. Explicit expressions are derived for the mean and standard deviation of the packet delay, as well as for the packet delivery ratio (PDR) at the MAC layer in an unsaturated network formed by moving vehicles on a highway. We validate the analytical results using extensive simulations and show that good accuracy can be achieved with the proposed model for a range of topologies and traffic load conditions. More importantly, using the model, we show that hidden terminals can have a severe, detrimental impact on the PDR, which may compromise the reliability required for safety applications.

Trust Management for VANETs

2012 ◽  
Vol 3 (1) ◽  
pp. 48-62 ◽  
Author(s):  
Jie Zhang
Keyword(s):  
Road Safety ◽  
Trust Management ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
False Information ◽  
Future Directions ◽  
Vehicle Communication ◽  
Vehicle To Vehicle ◽  
Trust Models ◽  
Hoc Networks

An increasingly large number of cars are being equipped with GPS and Wi-Fi devices, forming vehicular ad-hoc networks (VANETs) and enabling vehicle to vehicle communication with the goal of providing increased passenger and road safety. However, dishonest peers (vehicles) in a VANET may send out false information to maximize their own utility. Given the dire consequences of acting on false information in this context, there is a serious need to establish trust among peers. This article first discusses the challenges for trust management caused by the important characteristics of VANET environments, and identifies desired properties that effective trust management should incorporate in order to address the challenges. The author then surveys and evaluates existing trust models in VANETs, and points out that none of the trust models has achieved all the properties. Finally, the author proposes some important future directions for research towards effective trust management for VANETs.

Sign in / Sign up

Export Citation Format

Share Document