A Contention-Free Cooperative MAC Protocol for Eliminating Heterogenous Collisions in Vehicular Ad Hoc Networks

Abstract

In vehicular ad hoc networks (VANETs), efficient data dissemination to a specified number of vehicles with minimum collisions and limited access delay is critical for accident prevention in road safety. However, packet collisions have a significant impact on access delay, and they may lead to unanticipated link failure when a range of diversified collisions are combined due to complex traffic conditions and rapid changes in network topology. In this paper, we propose a distributed contention-free cooperative medium access control (CFC-MAC) protocol to reduce heterogenous collisions and unintended access delay in stochastic traffic scenarios. Firstly, we develop a cooperative communication system model and cooperative forwarding mechanism to explore the optimum road path between the source and destination by identifying the potential cooperative vehicles. Secondly, we propose a vectorized trajectory estimation mechanism to suppress merging collisions by identifying the relative velocity of vehicles with different speeds in a specific time interval. Based on the case study, typical heterogeneous collisions and aggregated heterogeneous collisions at dissociated positions and associated positions are investigated. In both cases, we propose the corresponding collision-resolving mechanisms by methodically recapturing the colliding time slot or acquiring the available free time slots after identifying the access vehicles and comparing the received signal strengths. Performance analysis for collision probability and access delay is conducted. Finally, the simulation results show that the proposed protocol can achieve deterministic access delay and a minimal collision rate, substantially outperforming the existing solutions.

A Preemptive-Resume Priority MAC Protocol for Efficient BSM Transmission in UAV-Assisted VANETs

“…Unlike Refs. [29][30][31][32][33][34][35][36][37][38][39][40][41], our work comprehensively considers these three aspects, which we believe will lead to better results.…”

“…The paper also provided detailed deployment schemes for unmanned aerial vehicles, demonstrating that the protocol effectively improves network throughput, latency, and reliability while ensuring fair sharing and balanced resource utilization among vehicles with different priorities. In [37], the author Linn aimed to design a conflict-free cooperative MAC protocol to address the issue of heterogeneous collisions in VANETs caused by differences in vehicle speeds, communication ranges, and data transmission requirements. The protocol utilizes a cooperation mechanism among vehicles by dividing neighboring vehicles into multiple groups, where only one vehicle in each group is allowed to transmit data, while others act as relay nodes for data forwarding.…”

Effectiveness of Vehicular Communication Using NP-CSMA with Bernoulli-Based Gaussian Interpolation Function

“…One of the most extensively used Media Access Control (MAC) protocols, Carrier Sense Several Access (CSMA), enables multiple users to share a single transmission channel, such as Ethernet and 802.11 wireless LAN. Carrier Sense Multiple Access (CSMA) is a much research and applied Media Access Control (MAC) protocols, as it allows multiple users to share a common communication medium [17], [18], [19], [20].…”