A minimum contention window adjustment method based on the estimation of the number of neighbor nodes in vehicular network

A technology of competition window and neighbor node, applied in the field of in-vehicle network, can solve the problem of not using RTS/CTS handshake protocol, not using BEB, etc.

Active Publication Date: 2016-03-09
NANJING UNIV OF POSTS & TELECOMM
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, although the binary exponential backoff method of IEEE802.11MAC layer can improve the scalability of unicast message transmission, in broadcast environment, we can neither utilize BEB nor RTS / CTS handshake protocol

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A minimum contention window adjustment method based on the estimation of the number of neighbor nodes in vehicular network
  • A minimum contention window adjustment method based on the estimation of the number of neighbor nodes in vehicular network
  • A minimum contention window adjustment method based on the estimation of the number of neighbor nodes in vehicular network

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0063] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings.

[0064] We use VanetMobiSim and NS2.35 to simulate and verify the method proposed by the present invention, and compare the performance of the minimum contention window adjustment method based on the estimation of the number of neighbor nodes with the original fixed-size initial contention window. In the broadcast performance simulation process of IEEE802.11p, each node works on the control channel CCH, and periodically broadcasts data frames to its one-hop neighbor nodes, and all broadcast frames have the same priority. The present invention will use the PBCAgent in the latest NS2.35 to generate periodic broadcast frames. The broadcast frame size is 250 bytes, and the broadcast frame generation frequency is 5Hz. Considering the mobility of vehicles, we built a highway scene under VanetMobiSim. In this scene, there are four two-way lanes in t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The purpose of the present invention is to solve the scalability problem of the MAC layer broadcast in the vehicular ad hoc network with rapid changes in vehicle density, and discloses a method for adjusting the minimum contention window based on the estimation of the number of neighbor nodes in the vehicular network. Under the premise of frame collision probability, the relationship between the minimum competition window and the number of competition nodes is deduced, and the value of the minimum competition window is dynamically adjusted through the real-time estimation of the number of neighbor nodes of the vehicle, so that the change of the minimum competition window value reflects Competition conditions in the network, thereby reducing collisions, reducing waste of channel resources, and improving broadcast performance. For the purpose of minimizing the collision probability, the present invention derives the relationship between CWmin and the number n of active competing nodes, and adaptively adjusts the minimum competition window by estimating the number of neighbor nodes of the vehicle in real time, so that the adjustment of the minimum competition window reflects the vehicle density Changes to improve IEEE802.11p? Scalability of MAC layer broadcast.

Description

technical field [0001] The invention relates to the field of vehicle network technology, in particular to a minimum contention window adjustment method based on the estimation of the number of neighbor nodes in the vehicle network. Background technique [0002] In the wireless vehicular ad hoc network, IEEE established a wireless access in vehicular environment (WirelessAccessinVehicularEnvironment, WAVE) working group, which is responsible for formulating the WAVE protocol stack for vehicular communication. The bottom layer of the WAVE protocol stack adopts the IEEE802.11p protocol [1] . Among them, the MAC layer of IEEE802.11p defines how different competing nodes access the network on a single control channel or service channel. The MAC layer of IEEE802.11p adopts the distributed coordination function DCF, and DCF has two operation modes of broadcast and unicast. For safety-related applications on the control channel, messages are mainly transmitted in broadcast mode, ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H04L12/807H04W84/18H04L47/27
Inventor 刘南杰刘委婉李大鹏赵海涛黄波
Owner NANJING UNIV OF POSTS & TELECOMM
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products