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VANET Link Characteristics and
Analysis in Urban and Suburban
Scenarios
Authors:Yang Yang, Jun Xu,Da Cheng, Lihua Wu, Peng-ju Tan, Lin-tao Yang
Adviser: Yu-Chiang Li
Speaker: Gung-Shian Lin
Date:2010/06/14
International Conference on , vol., no.,
pp.84-88, 25-27 May 2008
南台科技大學
資訊工程系
Outline
1
2
Background and Related work
3
Experimental setup and Details
4
Experimental results and Analysis
5
2
Introduction
Conclusion
1. Introduction
 That environment affects the quality of the wireless
link in VANET greatly.
 We have built an application for wireless data
dissemination and visualization in VANET.
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2. Background and Related work
 Considering VANET are distributed, self-organizing
communication networks and are thus characterized
by very high node.
 As the IEEE 802.llp standard implemented in the
future, VANETs are expected to be of great benefit
for safety applications.
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3. Experimental setup and Details
 A. Relevant Definition
 The RSSI value per bit is directly related to the SNR (Signal
to noise ratio) per bit.
 The packet loss rate (PLR) is the ratio of the number of lost
packets to the total number of packets transmitted per
second.
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3. Experimental setup and Details
 B. General Setup
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3. Experimental setup and Details
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4. Experimental results and Analysis
 A. Effect of Environmental Diversity to Wireless Link
 We perform the experiment in suburban and urban
scenarios, which are representative in wireless channel in
VANET.
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4. Experimental results and Analysis
 B. Effects of RSSI to VANET Wireless Link
 We calculate the average of the RSSI values according to
the different distance scales, and then compare them with
the average of PLR in the same scenario.
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4. Experimental results and Analysis
 C. Predicting the VANET wireless link By PLBL
 1. Experiment Results
• we define the number of the lost sequential packets in a time as
Packet loss Burst Length (PLBL).
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4. Experimental results and Analysis
• We calculate the possibilities of PLBL per time unit, categorize
them by distance scales, and then compare the average tendency
with PLR's.
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5. Conclusion
 Environment affects the quality of the wireless link in
VANET greatly
 At the communication distance range, in most extend,
the PLR is related to the distance variation.
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 RSSI is not coherent with PLR, which is not helpful in
predicting the quality of the VANET wireless link.
 In certain aspects, the sum of possibilities of PLBL is
another way to predict the 802.11 wireless channel
quality.
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南台科技大學
資訊工程系