Introduction

VOICE/DATA in 3G/4GVOICE/DATA in 3G/4G3G(WCDMA) 요금• 3G(WCDMA) 요금– 초과데이터이용료(i요금제): 5,000원/100MB (~2,000원(LTE))– Voice 데이터율: 12.2kbps x 2(양방향) 183kB/분– 100원/분 가정하면, (100원/분)/(183kB/분)=54,600원/100MB

10배 이상 차이 (음성 무제한 요금제 도입)

3G (WCDMA) 4G (LTE)음성 Circuit switching Packet switching

데이터 P k i hi P k i hi

• VoIP / mVoIP / VoLTE

데이터 Packet switching Packet switching

– VoLTE 품질은 어떻게?– VoLTE 요금은 어떻게?

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.22

Introduction

OTHER EMERGING TECHNOLOGIESOTHER EMERGING TECHNOLOGIES

M bil Ad H N t k• Mobile Ad-Hoc Networks• Wireless Sensor Networks• UWB• UWB• Cognitive Radio• Femtocell• Femtocell• Cooperative Communication• Visible Light Communication• Visible Light Communication• Wireless Power Transmission & Near Field

Communication• Compressed sensing• M2M Communication

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Introduction

MOBILE AD HOC NETWORKS (MANET)MOBILE AD-HOC NETWORKS (MANET)

• What is MANET?– A set of mobile hosts capable communication with each

other without the assistance of base station.– No backbone infrastructure.

R i b l ih– Routing can be multihop.– Topology is dynamic.

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Introduction

WIRELESS SENSOR NETWORKSWIRELESS SENSOR NETWORKS

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Introduction

WIRELESS SENSOR NETWORKS (cont’d)WIRELESS SENSOR NETWORKS (cont d)

• Characteristics of Sensor Network– Nodes powered by nonrechargeable batteriesp y g– Data flows to centralized location

Low per node rates but up to 100 000 nodes– Low per-node rates but up to 100,000 nodes– Data highly correlated in time and space

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.26

Introduction

UWBUWB

• UWB-RT (Ultra Wideband Radio Technology)– Short-range wireless technology– Sharing the existing radio spectrum resources

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Introduction

Cognitive RadioCognitive Radio

• Characteristics of Cognitive Radio– Communication using unused frequenciesg q

• Most of the radio frequency spectrum is inefficiently utilized.

– Detecting unused frequencies

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Introduction

FemtocellFemtocell

• Characteristics of Femtocell– Small cellular base station in residential or small

business environments– Connected to the network via ADSL etcConnected to the network via ADSL, etc.

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Introduction

Cooperative CommunicationCooperative Communication

• Joint Transmission/Reception– Improving performance of cell edge usersp g p g

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Introduction

Visible Light CommunicationVisible Light Communication

• LED Communications– Communication by fast blink of LED lightsy g– Using worldwide infrastructure of LED lights

거실 까페/레스토랑

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Introduction

Wireless Power Transmission &Near Field Communication

+ 결제, 열쇠, 쿠폰다운, 스마트태그 등

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.32

Introduction

Compressed SensingCompressed Sensing

• Compressed/Compressive Sensing– Sampling less than Nyquist ratep g yq– Cost down of ADC, saving storage, etc.

Compressive sampling on compressible sparse– Compressive sampling on compressible sparse signals

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Introduction

M to M CommunicationM-to-M Communication– Person-to-Person Person-to-Machine Machine-to-Machine

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Cellular Systems

CELLULAR SYSTEMS

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.

Cellular Systems

FUNDAMENTALS OF CELLULAR SYSTEMSFUNDAMENTALS OF CELLULAR SYSTEMS

Ideal cell area

BSCell

MSAlternative

MS

Hexagonal cell area used in most models

Alternative shape of a cell

Illustration of a cell with a mobile station and a base station

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Cellular Systems

CELL SIZECELL SIZEService area

Service area

BS BS

BSService area

(Zone) BS BS BS

Early wireless system: Large zone BS BS

Small zone

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Cellular Systems

CONTROL/TRAFFIC CHANNELSCONTROL/TRAFFIC CHANNELS

Downlink / UplinkControl / TrafficDedicated / Shared

Base StationMobile Station

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Cellular Systems

HANDOFF(HANDOVER) REGIONHANDOFF(HANDOVER) REGIONSignal strengthSignal strength Signal strength

due to BSj

Signal strength due to BSi

Pi(x) Pj(x)

E

BS

E

BSMSPmin

BSi X1BSjX3 X4 X2X5 Xth

MS

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Cellular Systems

FREQUENCY REUSEFREQUENCY REUSEF2F7

F2F7 F1

F2

F3F6

F7

F1

F1 F3F6 F4F5 F2F7F1

F4F5 F2F7 F1 F3F6 F1

F1 F3F6 F4F5F1

F4F5Fx: Set of frequency

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.6

7 cell reuse cluster

Cellular Systems

COCHANNEL INTERFERENCECOCHANNEL INTERFERENCEFirst tier cochannel Base StationSecond tier cochannel Base StationSecond tier cochannel

Base Station

RR

D1

D5

D6

1

D2D4 Mobile Station

D3

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Serving Base Station

Cellular Systems

WORST CASEWORST CASE

R

DD5

D6

Mobile StationD1

D2D4

D3

Serving Base Station Co-channel Base Station

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Cellular Systems

COCHANNEL INTERFERENCE RATIOCOCHANNEL INTERFERENCE RATIO

• Cochannel interference ratio– Carrier-to-Interference Ratio (CIR)( )

∑== M

I

CceInterferen

CarrierIC

• For cluster size of 7, M=6∑=k

kIf1

For cluster size of 7, M 6

⎞⎛= 1C

γ

∑= ⎠

⎞⎜⎝⎛M

k

k

RDI

1

−γ

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.9

Cellular Systems

CELL SECTORINGCELL SECTORINGc

120o 120o

ab

c

ab

c

b ab

(a). Omni (b). 120o sector (c). 120o sector (alternative)

d f60o

90o

ac

da

bd

ef

( ) 60o t(d) 90o t

bb

cd

Mobile Communications Engineering, Spring 2014 Jae Kyun Kwon, Yeungnam Univ.10

(e). 60o sector(d). 90o sector