15 march 2005 multi-standard convergence in mobile terminals (master thesis) presenter: shakeel...

15 March 2005

Multi-Standard Convergence in Mobile Terminals

(Master Thesis)

Presenter: Shakeel Ahmadvenue: GK Workshop Waldau, Germany.

Supervisors: M.Sc. Chunjiang YinProf. Dr. Hermann Rohling

Department of TelecommunicationTechnical University Hamburg Harburg

Presenter: Shakeel Ahmad

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Contents

• Introduction and Motivation

• Tasks

• Convergence Manager

• Simulation Scenario and Considerations

• Standard Selection Algorithms

• Implementation in MLDesigner

• Simulation Results

• Conclusions


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Introduction & Motivation

• An increased demand of mobile Internet

• A wired-like Internet service while on move… a big challenge

• The challenge seems hard to be met with pure 3G deployment

• WLAN a good candidate but suffers from low coverage

• In 4G system one proposal considers the convergence of the existing wireless standards

Convergence Manager


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Introduction & Motivation (2)

• Overall performance can be improved

• Potential benefits for end-users, network operator and the service provider


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Tasks

• Definition of a simulation scenario deploying multi-standard convergence

• Implementation of simulation scenario in MLDesigner• A quantitative analysis of the potential benefits offered

by multi-standard convergence only in mobile terminals– Standard selection algorithms and comparison

– Delay performance

– Request discarding rate performance


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Convergence Manager• Function:

– Enables the convergence of wireless standards.

• Location:– A crucial issue from architecture point of view– Some proposed locations for Convergence Manager (CM):

Only in Mobile Terminal Only in the network side Can be split into a network and Mobile Terminal part

Standard Selection


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Simulation Scenario & Considerations• A busy road about 1.5km long in a city and is crossed by some other roads

• Technological Scenario– Two standards, HSDPA (for UMTS) and HL2 (WLAN) were considered.

– HSDPA is available throughout and HL2 is available at crossings (100 m radius)

• User Scenario– Uniform spatial distribution along the road, moving with a constant speed.

– Users make request for a service according to Poisson process

• Service Scenario

– Generic file download service


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Contents


• Tasks






• Conclusions


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Switched Algorithm–Upon arriving a request, the highest data rate bearer is selected. –Download starts immediately and can take place via multiple standards–Switching between standards while mid of file download (complications involved)

Standard Selection Algorithms

UMTS Only UMTS OnlyUMTS / HL2 UMTS / HL2

Request

Request

Request

Request

Request

Request

Request

RequestRequestRequest

time

time

time

Switched

Current

Location

UMTS Only

Road

Three algorithms for standard selection were considered [1]

[1] MultiStandard approach for enhanced communications service provision to rail commuter IST Mobile Communications Summit, Lyon, France.

Location Algorithm–Uses additional knowledge of users‘s mobility, geographical coverage of standards and the mean data rate, to make more intelligent decision–Download may not start immediately and always takes place via single standard

Current Algorithm–Upon arriving a request, the highest data rate bearer is selected. –Download starts immediately and takes place via single standard

Initial delay


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Implementation in MLDesigner

Simulation Scenario


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Implementation in MLDesigner (2)

An instance of Mobile Terminal


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Contents


• Tasks






• Conclusions


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Multi-Standard Single-User Case• Request arrival Process is Poisson with mean rate of 1/10 requests per second, File

Size Fixed• It is supposed that user is moving with constant speed (10 m/s), Red Signal On

Probability=0.0• Mean Initial Delay Vs File Size & Mean Total File Download Time Vs File Size


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Multi-Standard Single-User Case (2)• Request arrival is Poisson with mean rate of 1/10 requests per second, File Size

Fixed• It is supposed that user is moving with constant speed (10 m/s), Red Signal On

Probability=0.0• Mean Request Discarding Rate Vs File Size


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HotSpot Effect• Request arrival Process with mean 1/10 requests per second, File Size Fixed

• It is supposed that user is moving with constant speed (10 m/s), Red Signal On Probability =0.1 (Red Signal is On for 15 sec)

• Mean Total Download Time Vs File Size

Crossing points are good place to install HL2 APs


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Multi-Standard Multi-User Case• Request arrival Process with mean 1/10 requests per second, File Size = 125 KB

• Users spatial distribution is uniform along the road,

• It is supposed that users are moving with constant speed (10 m/s), Red Signal On Probability =0.0

• Mean Total Download Time & Mean Request Discarding Rate Vs numUsers


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Problem with Location Algorithm

• Proposed Solution:

History Based Location AlgorithmMean data rate for the current file download via standard x is inferred from previous file download via standard x.

UMTS Only UMTS OnlyUMTS / HL2 UMTS / HL2

Request RequestRequestRequest

time

Location

UMTS Only

Road

• Wrong data rate estimation leads to wrong standard selection


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Performance of History Based Location Algorithm

• Improvement by applying History Based Location Algorithm

• Mean Total Download Time & Mean Request Discarding Rate Vs numUsers


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Conclusion

• Benefits of Convergence Manager– Improved QoS and System performance

– Easy to realize – no standardization efforts

• Comparison of standard selection algorithms– Switched algorithm lower bound of performance - Location algorithm closest

match

– Location Algorithm – Poor performance in multi-users

– History Based Location Algorithm-one Possible Solution


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Conclusion (2)

• Modular and Extendable Simulation Setup– A useful off-shelf component

– The framework can be easily extended e.g., for other wireless standards, new standard selection algorithms and new scheduling policies can be incorporated and tested easily

• Future Work– The assumption that CM knows precisely about user‘s mobility, location and

geographical coverage of wireless standards may not be realistic – Source of error.

– New standard-selection algorithms for different scenarios and services


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Thanks for listening

15 march 2005 multi-standard convergence in mobile terminals (master thesis) presenter: shakeel...

Documents

standard selection slide

multistandard convergence

shakeel ahmad venue

convergence manager

service provider slide

introduction motivation

internet service

multiple standards