Self-adaptive media access control (MAC) protocol for vehicle-mounted wireless self-organized network

Abstract

The invention discloses a self-adaptive media access control (MAC) protocol for a vehicle-mounted wireless self-organized network, comprising a DR-ALOHA protocol which is used by a control channel and a strategy for accessing a business channel through a node dynamic selection competition method or a pre-reservation method, wherein the DR-ALOHA protocol dynamically adjusts the number of fixed-length time slot in a time division multiplexing principle so that the secure information of all nodes in a network can be transmitted reliably in real time, and is applicable to networks with the node density and the topological structure being dynamically changed; in the strategy of accessing the business channel through the node dynamic selection competition method or the pre-reservation method, firstly the switching threshold of a business channel access method is determined by theoretical analysis and mathematical deduction and then the business channel is accessed through the node dynamic selection competition method or the pre-reservation method by integrating the real-time channel utilization rate of the business channel, so that the channel utilization rate of the business channel can be the highest in any node density.

Description

technical field [0001] The invention belongs to the technical field of wireless networks, and in particular relates to a new self-adaptive medium access control (MAC) protocol of a vehicle-mounted wireless self-organizing network. Background technique [0002] As an important branch of mobile wireless ad hoc network (MANET), the vehicle wireless ad hoc network (VANET) is designed to quickly form a network through mutual communication between vehicles driving along the road, and between vehicles and fixed access points. Form a wireless mobile ad hoc network that is easy to deploy, low in cost, and open in structure, thereby providing open public road traffic safety services and security-independent services such as traffic information query, personal communication, electronic map update, entertainment download, and Internet information. [0003] According to the IEEE 802.11p MAC protocol, WAVE (Wireless Access in Vehicle Environment) nodes need to compete for channels to send...

AI Technical Summary

Problems solved by technology

The RR-ALOHA protocol is used to transmit security, control, and business information, realizing real-time and reliable transmission of node security information. However, the RR-ALOHA protocol requires that the number of nodes in the network must be less than the number of time slots in a single frame, which cannot meet the requirements of VANET Characteristics of dynamic changes in node density and topology

At the same time, the MAC protocol still stipulates that the CCH time slot and the SCH time slot are both fixed values, so that the control channel and traffic channel cannot be fully utilized.

[0006] In recent years, research at home and abroad has achieved certain results, but there are still the following problems: it is impossible to maximize the channel utilization of traffic channels under any node density under the premise of ensuring security, real-time and reliable transmission of control information value

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