1 / 30

Cluster-Based Multi-Channel Communications Protocols in Vehicle Ad Hoc Networks

Cluster-Based Multi-Channel Communications Protocols in Vehicle Ad Hoc Networks. IEEE Wireless Communications october2006, vol.13 No. 5 指導老師：童曉儒 教授 報告人：張益瑞. Outline. INTRODUCTION SYSTEM ARCHITECTURE FUNCTIONS AND DESIGNS OF PROTOCOLS THE CLUSTER CONFIGURATION PROTOCOL

arvid
Download Presentation

Cluster-Based Multi-Channel Communications Protocols in Vehicle Ad Hoc Networks

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cluster-Based Multi-Channel Communications Protocols in Vehicle Ad Hoc Networks IEEE Wireless Communications october2006, vol.13 No. 5 指導老師：童曉儒 教授 報告人：張益瑞

  2. Outline • INTRODUCTION • SYSTEM ARCHITECTURE • FUNCTIONS AND DESIGNS OF PROTOCOLS • THE CLUSTER CONFIGURATION PROTOCOL • THE INTRACLUSTER COORDINATION AND COMMUNICATION PROTOCOL • SIMULATION EVALUATIONS • CONCLUSIONS

  3. INTRODUCTION(1/2) • What is DSRC(Dedicated ShortRange Communication)? • V2V-based VANETs and V2R-based VANETs. • The data transmitted over the VANETs can be classified into the real-time traffic and the non-real-time traffic.

  4. DSRC • DSRC/802.11p • The standard of 802.11p is based on IEEE 802.11a PHY layer and IEEE 802.11 MAC layer • Seven 10 MHz channels at 5.9GHz • one control channel and six service channels

  5. V2V-BASED VANETS AND V2R-BASED VANETS

  6. THE DATA TRANSMITTED OVER THE VANETS • real-time traffic • such as safety messages and video/audio signals • non-real-time traffic • such as e-maps and road/vehicle-traffic/weather information

  7. INTRODUCTION(2/2) • Our proposed scheme mainly consists of following three core protocols. • Cluster Configuration Protocol • Intracluster Coordination and Communication Protocol • Intercluster Communication Protocol

  8. SYSTEM ARCHITECTURE • Four Broadcasting Strategies • Probability-based • Location-based • Neighbor-based • Cluster-based

  9. FOUR BROADCASTING STRATEGIES • 1. Probability-based: • A given PDF determines the decision, for example depending on the number of copies a node has received. • The strategy is often dynamic. • PDF = probability distribution function

  10. PROBABILITY-BASED

  11. FOUR BROADCASTING STRATEGIES • Location-based • The selection criterion is the amount of additional area that would be covered by enabling a node to forward. • Some proposal also computes position prediction as useful input information.

  12. LOCATION-BASED

  13. FOUR BROADCASTING STRATEGIES • Neighbor-based • A node is selected depending on its neighbors status (for instance, the status concerns how a neighbor is connected to the network).

  14. NEIGHBOR-BASED

  15. FOUR BROADCASTING STRATEGIES • Cluster-based • Nodes are grouped in clusters represented by an elected cluster-head. Only cluster-heads forward packets. • Nodes in the same cluster share some features (e.g., relative speed in VANETs). • Reclustering on-demand or periodically.

  16. CLUSTER-BASED

  17. SYSTEM ARCHITECTURE

  18. SYSTEM ARCHITECTURE • Our proposed scheme handles the following three tasks • Cluster-membership management • Real-time traffic (such as safety messages delivery) • Non-real-time data communications (such as e-maps download, movies download, etc.)

  19. SYSTEM ARCHITECTURE

  20. 有限狀態機( FINITE STATE MACHINE, FSM) • 在現實中，有許多事情可以用有限個狀態來表達。 • 紅綠燈運作的原理相當簡單，從一開始綠燈，經過一段時間後，將變為黃燈，再隔一會兒，就會變成紅燈，如此不斷反覆。

  21. FUNCTIONS AND DESIGNS OF PROTOCOLS • We use the Finite State Machine (FSM) • Each vehicle operates under one and only one of the following four states at any given time: • cluster-head (CH) • quasi-cluster-head (QCH) • cluster-member (CM) • quasi-cluster-member (QCM)

  22. FUNCTIONS AND DESIGNS OF PROTOCOLS Finite state machine of our proposed scheme. T1 and T2 representTransceiver 1 and Transceiver 2

  23. THE INTRACLUSTER COORDINATION AND COMMUNICATION PROTOCOL Time division in the CRC channel

  24. THE INTRACLUSTER COORDINATION AND COMMUNICATION PROTOCOL Tt = 分時多工時間區段 N= 叢集內群組成員 gap = 平均車間距離 v = 平均車輛長度 Lc = 半徑 Nlane = 位於公路上的車道數量

  25. THE INTRACLUSTER COORDINATION AND COMMUNICATION PROTOCOL T=repetition period(重複期間，預設為200ms) R=channel rate Tsafety = 更新安全訊息的間隔時間 Hsafety = 安全訊息的packet size，預設為200bytes

  26. SIMULATION EVALUATIONS • 實驗情境設定 • 環境：單向3線道 • 進入時間：2100秒，變異數：180秒 • 平均速率：35m/s，變異數：15m2 / s2

  27. SIMULATION EVALUATIONS • 實驗工具：Matlab • 參數設定： • 車距：25m • 車長：5m • 車內半徑：150m • 車間半徑：400ms • 接收時間：150ms • 發送時間：50ms • 安全訊息封包大小：200bytes

  28. SIMULATION EVALUATIONS The performance of three protocols against non-real-time trafficarrival rate: a) Probability of safety-message-delivery failure; and b) aggregatethroughput of non-real-time traffics. The size of the non-real-time traffic packetis 512 bytes.

  29. SIMULATION EVALUATIONS Channel busy rates of the seven different channels. The size of thenon-real-time traffic packet is 512 bytes and the packet arrival rate of the nonreal-time traffic is 200packets/sec/vehicle.

  30. CONCLUSIONS • Reducedata-congestion • Support QoS for real-timedelivery of safety messages • High throughput

More Related