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國立雲林科技大學
National Yunlin University of Science and Technology
Analysis of Soft Handover Measurements in
3G Network
Advisor : Dr. Hsu
Student :Jing Wei Lin
2006.8.ACM.MSWiM
November 22, 2006
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Intelligent Database Systems Lab
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Outline
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Motivation
Objective
Introduction
Method
Experiments
Conclusions
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Motivation
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Mobility management is a great challenge in
current and future radio access networks.
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Objective
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We propose a method to find groups of similar
mobile cell pairs in the sense of soft handover
measurements(SHO).
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Introduction-SHO
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SHO-軟式訊號換手，當使用者在做訊號換手動作時，系統連線是先建立新的
連線後才將原來的連線中斷，使訊號進行轉換時不易被使用者察覺。
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In 3G system, Mobile Station (MS) is moving towards another Base Station (BS),
the MS should have a connection at least on one BS all the time by SHO.
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When MS is in SHO, several BSs listen the same uplink channel, but all BSs have
their own downlink channel. There is a tradeoff between better QoS in mobility
management and consumption of resources.
Cell
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Method
Finding groups of similarly
behaving cell pairs in SHO
situations.
1.
2.
3.
Data vectors are at
first used to train a
Self-Organizing Map.
The codebook vectors
are further clustered
using hierarchical
clustering method.
The number of
clusters can be
selected manually.
(Here use DBI to do)
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Variable selection
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Preprocessing
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The method was selected on
basis of histograms
Logarithms of some of the
variables were taken, but
finally only scaled
EcnoDiffNum was
preprocessed with
logarithmic function.
Sample vectors with 15 or
more missing values in 20
variables are canceled.
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Experiment
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Experiment
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Experiment
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lower
higher
N.Y.U.S.T.
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9
5
lower
higher
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Conclusions
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The benefits of the proposed method are the decrease in
computational complexity due to used two-phase clustering
algorithm and the visualization capability of the method.
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The histograms are used both when preprocessing methods are
decided and when an interpretation for the found clusters are
looked for.
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