ABSTRACT

A vehicular ad hoc network (VANET) is designed to enable efficient and authentic node/infrastructure communication. The primary role of VANETs is to distribute time-sensitive safety messages (sm) regularly, which causes packet congestion and broadcast failure due to the network’s limited spectrum. For efficient and reliable delivery, the proposed paper uses a spatial hybrid division multiple access (SDMA) and time division multiple access (TDMA) over the control channel interval and hence termed a spatially distributed multichannel MAC (SDM-MAC) protocol. The frequency reuse approach is used to transfer data while efficiently utilising bandwidth, and throughput is considerably enhanced with carrier sense multiple access with collision avoidance (CSMA/CA) and with the help of TDMA. Moreover, an adaptive algorithm is proposed for an intelligent channel frame structure using this protocol to manage the highly dynamic scenario. The Markov chain defines the protocol, and the network simulator (NS2) analyses several performance metrics. Comparing the response with two existing MAC protocols, the proposed protocol reduces average latency compared to current MAC methods and improves the packet delivery ratio and throughput by an average of 26% and 28%, respectively.

摘要

车载自组织网络 (VANET) 旨在实现高效且可靠的节点/基础设施通信。VANET 的主要作用是定期分发时间敏感的安全消息 (sm)，由于网络的频谱有限，这会导致数据包拥塞和广播失败。为了高效和可靠地交付，所提出的论文在控制信道间隔上使用空间混合分多址 (SDMA) 和时分多址 (TDMA)，因此称为空间分布式多信道 MAC (SDM-MAC) 协议。频率重用方法用于在有效利用带宽的同时传输数据，并且在 TDMA 的帮助下，通过带冲突避免的载波侦听多路访问 (CSMA/CA) 显着提高了吞吐量。而且，针对使用该协议管理高度动态场景的智能信道帧结构，提出了一种自适应算法。马尔可夫链定义了协议，网络模拟器 (NS2) 分析了几个性能指标。将响应与两个现有的 MAC 协议进行比较，与当前的 MAC 方法相比，所提出的协议减少了平均延迟，并将数据包传递率和吞吐量分别平均提高了 26% 和 28%。