Joint Optimization of Multi-Hop Broadcast Protocol and MAC Protocol in Vehicular Ad Hoc Networks

Beacon messages and emergency messages in vehicular ad hoc networks (VANETs) require a lower delay and higher reliability. The optimal MAC protocol can effectively reduce data collision in VANETs communication, thus minimizing delay and improving reliability. In this paper, we propose a Q-learning MAC protocol based on detecting the number of two-hop neighbors. The number of two-hop neighbors in highway scenarios is calculated with very little overhead using the beacon messages and neighbor locations to reduce the impact of hidden nodes. Vehicle nodes are regarded as agents, using Q-learning and beacon messages to train the near-optimal contention window value of the MAC layer under different vehicle densities to reduce the collision probability of beacon messages. Furthermore, based on the contention window value after training, a multi-hop broadcast protocol combined with contention window adjustment for emergency messages in highway scenarios is proposed to reduce forwarding delay and improve forwarding reliability. We use the trained contention window value and the state information of neighboring vehicles to assign an appropriate forwarding waiting time to the forwarding node. Simulation experiments are conducted to evaluate the proposed MAC protocol and multi-hop broadcast protocol and compare them with other related protocols. The results show that our proposed protocols outperform the other related protocols on several different evaluation metrics.

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FL-ASB: A Fuzzy Logic Based Adaptive-period Single-hop Broadcast Protocol

International Journal of Distributed Sensor Networks ◽

10.1177/1550147718778482 ◽

2018 ◽

Vol 14 (5) ◽

pp. 155014771877848

Author(s):

Bin Pan ◽

Hao Wu ◽

Jin Wang

Keyword(s):

Fuzzy Logic ◽

Ad Hoc Networks ◽

Vehicular Ad Hoc Networks ◽

Ad Hoc ◽

Delivery Ratio ◽

Inference System ◽

Network Load ◽

Hoc Networks ◽

The Impact ◽

Broadcast Protocol

In vehicular ad hoc networks, vehicle-to-vehicle–based broadcast can fast disseminate safety messages between vehicles within the whole network and hence expand drivers perception vision, which will reduce the accident probability and ensure the transportation reliability. As for fixed-period single-hop broadcast protocol, disseminating safety messages frequently can cause excessive network load. However, increasing period purely does not guarantee the real-time performance. In addition, exiting adaptive-period single-hop broadcast protocols also have limitations without considering synthetically various impact factors. Thus, how to design a single-hop broadcast protocol that can dynamically adjust the broadcast period according to the actual road condition is a pressing issue. A Fuzzy Logic Based Adaptive-period Single-hop Broadcast Protocol in vehicular ad hoc networks is designed in this article, which provides a new solution for the dissemination of period safety messages. In this article, the impact of various factors (such as the number of one-hop neighbor nodes, vehicle speed, received signal strength index, and visibility) on the single-hop broadcast period has been analyzed. In view of each impact factor, we design corresponding membership function and fuzzy rules according to the specific scenarios and parameters. It realizes the adaptive changes of period safety messages broadcast period through the simulation of the proposed fuzzy logic inference system. Finally, we verify the performance of the Fuzzy Logic Based Adaptive-period Single-hop Broadcast Protocol in a bidirectional four-lane highway scenario. Simulation results show that the proposed Fuzzy Logic Based Adaptive-period Single-hop Broadcast Protocol has obvious advantages in terms of network load ratio, average one-hop delay, and delivery ratio.

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Performance Analysis of a Flexible MAC Protocol for Real-Time Services in Vehicular Ad-Hoc Networks

International Journal of Wireless Information Networks ◽

10.1007/s10776-005-0002-1 ◽

2005 ◽

Vol 12 (3) ◽

pp. 147-157

Author(s):

Giuseppe Caizzone ◽

Paolo Giacomazzi ◽

Luigi Musumeci ◽

Gabriella Saddemi ◽

Giacomo Verticale

Keyword(s):

Performance Analysis ◽

Ad Hoc Networks ◽

Real Time ◽

Vehicular Ad Hoc Networks ◽

Ad Hoc ◽

Mac Protocol ◽

Hoc Networks

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Flying Ad Hoc Networks: A New Domain for Network Communications

Sensors ◽

10.3390/s18103571 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3571 ◽

Cited By ~ 34

Author(s):

Antonio Guillen-Perez ◽

Maria-Dolores Cano

Keyword(s):

Ad Hoc Networks ◽

Vehicular Ad Hoc Networks ◽

Ad Hoc ◽

Added Value ◽

Research Activities ◽

Communication Links ◽

Communication Devices ◽

Hoc Networks ◽

5 Ghz ◽

The Impact

The advent of flying ad hoc networks (FANETs) has opened an opportunity to create new added-value services. Even though it is clear that these networks share common features with its predecessors, e.g., with mobile ad hoc networks and with vehicular ad hoc networks, there are several unique characteristics that make FANETs different. These distinctive features impose a series of guidelines to be considered for its successful deployment. Particularly, the use of FANETs for telecommunication services presents demanding challenges in terms of quality of service, energy efficiency, scalability, and adaptability. The proper use of models in research activities will undoubtedly assist to solve those challenges. Therefore, in this paper, we review mobility, positioning, and propagation models proposed for FANETs in the related scientific literature. A common limitation that affects these three topics is the lack of studies evaluating the influence that the unmanned aerial vehicles (UAV) may have in the on-board/embedded communication devices, usually just assuming isotropic or omnidirectional radiation patterns. For this reason, we also investigate in this work the radiation pattern of an 802.11 n/ac (WiFi) device embedded in a UAV working on both the 2.4 and 5 GHz bands. Our findings show that the impact of the UAV is not negligible, representing up to a 10 dB drop for some angles of the communication links.

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ACK-CAST: ACK-Based Broadcast Protocol for Vehicular Ad Hoc Networks

IEICE Transactions on Communications ◽

10.1587/transcom.e97.b.960 ◽

2014 ◽

Vol E97.B (5) ◽

pp. 960-966

Author(s):

Ajmal KHAN ◽

Jae-Choong NAM ◽

You-Ze CHO

Keyword(s):

Ad Hoc Networks ◽

Vehicular Ad Hoc Networks ◽

Ad Hoc ◽

Hoc Networks ◽

Broadcast Protocol

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Hybrid power control and contention window adaptation for channel congestion problem in internet of vehicles network

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v12i1.pp497-505 ◽

2022 ◽

Vol 12 (1) ◽

pp. 497

Author(s):

Hayder M. Amer ◽

Ethar Abduljabbar Hadi ◽

Lamyaa Ghaleb Shihab ◽

Hawraa H. Al Mohammed ◽

Mohammed J. Khami

Keyword(s):

Ad Hoc Networks ◽

Power Control ◽

Congestion Control ◽

Vehicular Ad Hoc Networks ◽

Ad Hoc ◽

Wireless Channel ◽

Contention Window ◽

Internet Of Vehicles ◽

Hybrid Power ◽

Hoc Networks

Technology such as vehicular ad hoc networks can be used to enhance the convenience and safety of passenger and drivers. The vehicular ad hoc networks safety applications suffer from performance degradation due to channel congestion in high-density situations. In order to improve vehicular ad hoc networks reliability, performance, and safety, wireless channel congestion should be examined. Features of vehicular networks such as high transmission frequency, fast topology change, high mobility, high disconnection make the congestion control is a challenging task. In this paper, a new congestion control approach is proposed based on the concept of hybrid power control and contention window to ensure a reliable and safe communications architecture within the internet of vehicles network. The proposed approach performance is investigated using an urban scenario. Simulation results show that the network performance has been enhanced by using the hybrid developed strategy in terms of received messages, delay time, messages loss, data collision and congestion ratio.

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A TDMA-Based MAC Protocol for Mitigating Mobility-Caused Packet Collisions in Vehicular Ad Hoc Networks

Sensors ◽

10.3390/s22020643 ◽

2022 ◽

Vol 22 (2) ◽

pp. 643

Author(s):

Muhammad Bilal Latif ◽

Feng Liu ◽

Kai Liu

Keyword(s):

Ad Hoc Networks ◽

Vehicular Ad Hoc Networks ◽

Ad Hoc ◽

Time Slot ◽

Mac Protocol ◽

Autonomous Driving ◽

Message Delivery ◽

Average Delay ◽

Stringent Requirement ◽

Hoc Networks

An autonomous driving environment poses a very stringent requirement for the timely delivery of safety messages in vehicular ad hoc networks (VANETs). Time division multiple access (TDMA)-based medium access control (MAC) protocols are considered a promising solution because of their time-bound message delivery. However, in the event of mobility-caused packet collisions, they may experience an unpredicted and extended delay in delivering messages, which can cause catastrophic accidents. To solve this problem, a distributed TDMA-based MAC protocol with mobility-caused collision mitigation (MCCM-MAC) is presented in this paper. The protocol uses a novel mechanism to detect merging collisions and mitigates them by avoiding subsequent access collisions. One vehicle in the merging collisions retains the time slot, and the others release the slot. The common neighboring vehicles can timely suggest a suitable new time slot for the vacating vehicles, which can avoid access collisions between their packet transmissions. A tie-breakup mechanism is employed to avoid further access collisions. Simulation results show that the proposed protocol reduces packet loss more than the existing methods. Consequently, the average delay between the successfully delivered periodic messages is also reduced.

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