In-vehicle network unicast routing method self-adapted to vehicle density

Abstract

Provided is an in-vehicle network unicast routing method self-adapted to vehicle density. The routing processes of the in-vehicle network unicast routing method comprise the routing process for mobile nodes and the routing process for static nodes. The routing process for the mobile nodes comprises the following steps of maintaining neighbor state information, sending a report message, sending a departure message, sending a routing request, receiving a routing response and forwarding a message. The routing process for the static nodes comprises the following steps of maintaining the neighbor state information, maintaining a road density value table, maintaining a road time delay table, receiving the routing request, replying a response message and giving a notice of road density changes. When network density is low, the mobile nodes can automatically increase a communication radius and prolong datagram lifetime, so that the success rate is increased within the time delay range required by an application; when network intensity is high, the mobile nodes automatically reduce the communication radius and shorten the datagram lifetime, so that signal collisions in the communication process are reduced while the success rate is increased and time delay is decreased. A good balance is realized between the success rate, time delay and expenditure.

Description

technical field [0001] The present invention relates to a vehicle-mounted network unicast routing method, more particularly, a vehicle-mounted network unicast routing method oriented to network density heterogeneity and static node assistance, that is, a vehicle-mounted network unicast that adapts to vehicle density A routing method belongs to the technical field of vehicle network communication. Background technique [0002] Vehicular network is a mobile ad hoc network composed of mobile vehicles loaded with sensors with wireless communication capabilities. As an emerging network form, the benefits and research challenges it brings are becoming increasingly apparent. The in-vehicle network makes it possible to share data between vehicles. The following requirements can be realized by routing between vehicles: any vehicle can distribute the information generated by itself to other vehicles; any vehicle can communicate with electronic devices at home thousands of miles away ...

AI Technical Summary

Problems solved by technology

This type of routing needs to frequently deal with connection interruptions in order to maintain the topology. The overhead is very high, but the success rate is very low. It is only suitable for networks with uniform density and stable topology.

The second type is node-based routing. This type of routing requires each node to calculate the route based on the information it collects (including traffic flow information and vehicle status information). The information that nodes in this type of routing can obtain is limited. Once If you enter a road without nodes, you will not be able to find subsequent routes. When transmitting at intersections, you will not consider the shelter of buildings, resulting in a high packet loss rate, which is only applicable to networks with high density; the third type of routing is based on intersections. This type of routing is only routed at the intersection. Generally, the mobile node makes the routing decision when it arrives at the intersection, or sets a static node at the intersection, and the static node makes the routing decision. This type of routing has a good balance between success rate and cost. , but when the network density is low, the delay is greatly increased and cannot adapt to changes in network density

The mobile node dynamically adjusts the period of the broadcast message according to the status of the neighboring vehicles. When the density is high, the broadcast frequency is reduced, and when the density is low, the broadcast frequency is increased, which effectively limits the overhead.

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