C01 1 Overview

Wireless communicationsOverview

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Dept. of Information Communication Engineering, Chosun University 1.1

ANT ANT Fading diversity

CT (Cordless Telephone, ) TRS (Trunked Radio System ) TRS (Trunked Radio System, ) Mobile communication

z Multiple access (CDMA, TDMA, FDMA)Wi l LAN Wireless LAN

Bluetooth


( , )


ANT

:

. :

. : .

: : . , ,

f , c .z [m] = c [m/sec] / f [Hz] , c=3108 [m/sec]z 300 Mhz 1 mz 30 Ghz 1 cm

X, . .

600 TH 0 4 0 7 iz : 600 THz 0.4 ~ 0.7 micrometer


Maxwell

electric field

TimeTime

magnetic field [Propagation of electromagnetic wave]


(radiation)

1. , .2. , . 3. , . 4. , .


ANT()

/2 Dipole Antenna /2 omni- /2 , omni-

directional .

Antenna (Reciprocal)


ANT()Radiation pattern

(a) omni-directional radiation(a) directional radiation( )


Antenna Gain

, omnidirectional antenna (isotropic antenna) ( p )

(effective area)

z G = antenna gainz A = effective areaz Ae = effective areaz f = carrier frequencyz c = speed of light ( 3 108 m/s)z = carrier wavelengthz = carrier wavelength

244 AfAG ee == 22 cG ==


Antenna Gain

) 12GHz 2m , ?

2A 2

8 9

0.56 0.56

/ (3 10 ) /(12 10 ) 0.025[ ]e

A rA A

c f m

= == =

= = =2 2

10

/ (3 10 ) /(12 10 ) 0.025[ ] (2.24 ) /(0.025 ) 35,373

10log (35,373) 45.49[dB]dB

c f mG

G

= =

= =


ANT

() : . () : . () : , , , .

() : , () : - . ( )() : .

() : , () VHF() : , , VHF. () : , . () : . , . .

() : . , . () : () : . () : . () : . .


= = = electromagnetic wave 3000GHz ( 0.1mm) . , . . . -

. .

, . .

. . 2 .(fading)

. (FM AM, PCS )


Satellite DMB

Dept. of Information Communication Engineering, Chosun University 16

: 19011902 (Heaviside) (Kennely) 19011902 (Heaviside) (Kennely) 50400 km .

D : 5090km . , . LF() MF() .

E : 100 km . . D . . MF() HF() ( ) ( )LF . E 1000km .

F : 200400km . F1 200km F2 250400km 200km F2 250400km . 280km . HF() VHF() . .


z , .

z : : : , ,

z

.z

.


- . , , .

. .


: .

F , F

D 101 .

1,2 .

( )

,

- : ( , ), -

- : ( : ) - : ( : )

( - : ( : .)

, , ,


(multipath fading)

(multipath fading) ,

, ,


(reflection) :

(diffraction) : 2

(scattering) : (scattering) :

(shadowing) . .


(fading)

LF, MF, HF () :

.

: . ANT ,

: .

: .

: : . ,

VHF () (S i till ti f di ) (Scintillation fading) :

K : K .

(DUCT) : .


(Diversity)

z : 2 3 ANT ()

z : 2 2 ()

z : , ANT z :

AGC AGC AGC : AGC

:

AVC() (Limiter)


[] 2008.5.10

. [ ]


CT (Cordless Telephone)

CT-1( ) 20m .

CT-2(cityphone) 200~300m Handover Handover . 5000/Km2

( : 25/Km2) FDMA, TDD, 964.1~868.1 MHz, ADPCM 32Kbps

CT 3CT-3 200~300m TDMA/DCA TDD 1 88~1 99GHz ADPCM 32Kbps TDMA/DCA, TDD, 1.88 1.99GHz, ADPCM 32Kbps

DECT : /, (), , GSM ( :300m) GSM ( 300m)

PHD : , 64Kbps


TRS (Trunked Radio System, )

.

.

.

TRS .


TRS

(TRS) ()

806 ~ 821MHz851 866MH824 ~ 849MHZ869 894MH

150, 200, 400MH 851 ~ 866MHz 869 ~ 894MHz 400MHz

, (dialing) (dialing)

, , (Dial, PTT) (PTT)

0.5 10 0.5

120 / 30 /

, ,


TRS


(1)

z [] 1970 16km x 16km 12

z => z => z (frequency reuse)


(2)

z 6

f1

f6

Radio tower

f2

f3

f4

f5

3


(3)

z =>

f1 f2f5f6f3

f4

Low -power antenna

f3 f6

Low -power antenna

6

f1

3

Low -power antenna

3 f4

f5

6

Low -power antenna Low -power antennaLow -power antenna

1

f2

Low power antenna p

f1 f2

f5

f6

Low -power antennaLow -power antenna


ANT

Free space loss, ideal isotropic antenna

( ) ( )2

2

2

2 44 fddPt ==z Pt = signal power at transmitting antenna

22 cPr Pt signal power at transmitting antenna

z Pr = signal power at receiving antennaz = carrier wavelengthz d = propagation distance between antennasz c = speed of light (3x108 m/s)where d and are in the same units (e meters)where d and are in the same units (e.g., meters)


, , ->

Cell Type Cell Radius Coverage Services

Giga Cell 750 km Continents Satelliteg

Mega Cell 5 km ~ Rural Cellular

Macro Cell 2 ~ 5 km Urban/rural Cellular

TheoreticalPaper Model Real WorldMicro Cell 200 ~ 2 km DenseUrban

Cellular/Low-Tier system

Pico Cell 200 m Office,Low-Tier

system/WirelessPico Cell ~ 200 m Campus system/WirelessLAN


MS, BS, MSC, LR


(1)

(f d ll )z (fixed allocation)

z (dynamic allocation) MSC => MSC .

(handoff) . () (fading)

=>


CDMA


Cellular System

Hand off

1 2 n

No. 1 No. 2 No. n

......

Hand off : Hand off : Roaming :


3.

4.

Base Station

1. MIN,

2. MIN, .

6. PSTN

7.

5. MIN

Mobile Switching CenterMobileMIN,


Digital modulation

Modulation of digital signals known as Shift Keying

A lit d Shift K i (ASK)1 0 1

Amplitude Shift Keying (ASK): very simple low bandwidth requirements

tq

very susceptible to interference

Frequency Shift Keying (FSK):

1 0 1

Frequency Shift Keying (FSK): needs larger bandwidth t

Phase Shift Keying (PSK): more complex robust against interference

1 0 1

robust against interferencet


(FDMA) (TDMA) (TDMA) (CDMA)


Multiple Access

FDMA (FDMA ( ) ) , ()

FDMA

Power () . FDMA 20kHz -30kHz. AMPS(Advanced Mobile Phone System)FrequencyTime

TDMA (TDMA ( ) ) (Time Slot)

TDMA

Power . GSM 200kHz 8.

Frequency

Power

CDMA (CDMA ( ) ) (spread spectrum) 1 ,

q yTime

PowerCDMA

F


FrequencyTime

CDMA Cellular Network Infrastructure

OMCBSC

PLMN

J-STD-008,IS-95A

SMC

PSTN

BTS

MS

IPC

IPCChinese NO.7TSB 80

Ethernet/OSITMN Q3 Chinese NO.1, NO.7

IS-41

Chinese NO.1/No.7

Chinese NO.7/IS-41

PSTNPSTN

MSCBSM

GCINGCIN

IPC

IPC

IPC

TSB-80

IWFIWF

Chinese NO.7

LAPDChinese NO.7/NO.1 X.25

Chinese NO.7/IS-41C

Chinese NO.7

HLRVMS/FMS PSPDN

InformationProvider

IPC

J-STD-008,IS-95A

X.25

X.25Chinese NO.7/IS-41

Chinese NO.7TSB-80

InternetInternetBTS

BSC ProviderInternetInternetGatewayGateway

MS

TCP/IP

AuC

MS PSTNMSCBSCBTSCDMASignal

Q-CELPPacket

PCMData

PCMData

Dept. of Information Communication Engineering, Chosun University 1.45ChannelCard

Vocoder

2 3

(1G)

(1G)

2G2G 2.5G2.5G 3G3G

AMPSAMPS CDMA TDMACDMA TDMA CDMA TDMACDMA TDMA CDMACDMA AMPSAMPS CDMA, TDMACDMA, TDMA CDMA, TDMACDMA, TDMA CDMACDMA

-- 9.6 kbps9.6 kbps 144kbps144kbps 2Mbps2Mbps

800 900 MHz800 900 MHz 800 1 8 GHz800 1 8 GHz 800 1 8GHz800 1 8GHz 2 GHz2 GHz

800 ~ 900 MHz800 ~ 900 MHz 800 ~ 1.8 GHz800 ~ 1.8 GHz 800 ~ 1.8GHz800 ~ 1.8GHz 2 GHz2 GHz

25 ~ 30 kHz25 ~ 30 kHz 30kHz ~ 1.23MHz30kHz ~ 1.23MHz 30kHz ~ 1.23MHz30kHz ~ 1.23MHz 5 ~ 10 MHz5 ~ 10 MHz

()

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o ()

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19951995 19991999 20002000 20012001 20022002 2003 +2003 +1xEV-DO 1xEV-DV

IS-95-A IS-95-B cdma2000 1x(Phase 1)

14.4 kbps circuit

64 kbps Packet IS-95A

(1.5) 153 kbps Data IS-95A/B

2.4 Mbps Data IS-95A/B

cdma2000 3x

(Phase 2) Higher Cap Voice/ Data IS-95A/B

IMT-2000 All IP- IP Protocol

(1x 2) 384k ~ 2Mbps Data IS-95A/B

IS-136 EDGE (US)EDGE (Europe)

W CDMA

GSM GSM GPRS 9.6 kbps

W-CDMA(Europe, )

30-40 kbps Packet GSM

384 kbps Packet

High Capacity Voice 384+ kbps Packet(GSM/PDC)

28.8 kbps PDC

PDC 9.6 kbps

PDC+ W-CDMA(Japan)( )

* EDGE: Enhanced Data for GSM Evolution

GPRS: General Packet Radio Service

cdma2000/WCDMA Data - Data only HDR

Mi ti P th All IP

cdma2000/WCDMA Data - Data only HDR

Mi ti P th All IPDept. of Information Communication Engineering, Chosun University 1.47

Migration Path All-IP Migration Path All-IP

Wireless networking


Wireless LAN (WLAN)

- Network Hub Client (RF)- Network Hub Client (RF) .

LAN : - LAN : , , ISM Band Spread Spectrum LAN .

- ISM(Industrial, Scientific, Medical) Band. 902 - 928Mhz(26Mhz Bandwidth). 2.4 - 2.4835Ghz(83.5Mhz Bandwidth). 5.725 - 5.85Ghz(125Mhz Bandwidth)


Wireless LAN


Comparison: infrastructure vs. ad-hoc networks

infrastructuret knetwork

APAP: Access Point

APAP wired network

ad-hoc network


IEEE standard 802.11

mobile terminal

fixedterminal

mobile terminal

infrastructure

access point

infrastructurenetwork

application

TCP

application

TCP

802 11 MAC

IP

802 3 MAC 802 3 MAC

IP

802 11 MAC

LLCLLC LLC

802.11 PHY

802.11 MAC 802.3 MAC

802.3 PHY 802.3 PHY

802.3 MAC802.11 MAC

802.11 PHY


Wireless LAN

-

IEEE802 11b 2 4GH 11Mb S l ti. IEEE802.11b : 2.4GHz, 11Mbps Solution. IEEE802.11a : 5GHz, 24, 36, Max. 54Mbps Solution. HiperLAN : 25Mbps Solution. HiperLAN II : 36Mbps Solution

- Home Network Solution

-


Wireless LAN

- , , , ,

- , Network N t ki . Networking

. , , , ,

- Cabling . , , , ,

- , Network

- Network


Bluetooth

Harald BlueTooth 10

:

:

SIG


Bluetooth

Bluetooth (Ericsson) Nokia

1,790 LG SK 50 . , LG, SK 50 .

10m .10m .

. . Frequency hopping

3 . 10Mbps 2.0

1.1

.


Bluetooth

portable and/or fixed devices cable portable and/or fixed devices cable

short-range(10m) radio link robustness, low complexity, low power, low cost, p y, p , 2.4 GHz ISM band circuit packet switching combinationc rcu t pac t w tch ng c m nat n 1 asynchronous data ch. ( 721/57.6 kbps or 432.6/432.6

kbps) + 3 synchronous voice ch. (64kbps)p y p


BlueTooth Usage Model

The three-in-one phone

The Internet Bridge , PDA,


BlueTooth Usage Model

The interactive conference

PDA , PDA,


ZigBee http://www.zigbee.org/

ZigBee Philips Philips , , , 30 IEEE 802.15.4

.

. 20 1 . .

( : )( ) Ex)

ZigBee .

, .

B DZigBee : Smart Dust

.


ZigBee and Bluetooth

Bluetooth ZigBee

N E F E FHSS DSSSAIR INTERFACE FHSS DSSS

PROTOCOL STACK 250 kb 28 kbL K 5

BATTERY rechargeable non-rechargeable

DEVICES/NETWORK 8 255

LINK RATE 1 Mbps 250 kbps

RANGE ~10 meters (w/o pa) ~30 metersRANGE ~10 meters (w/o pa) ~30 meters

Comparison OverviewDept. of Information Communication Engineering, Chosun University 1.61

Comparison Overview

Home & Diagnostics Examples

DealerRetailer SOHO

Mobile clients link to PC for database storage PC links to peripherals, interactive toys PC Modem calls retailer, SOHO, Service

P idServiceProvider

ProviderGateway links to security system, temperature sensor, AC system, entertainment, health. G t li k t fi ld l / iC t Gateway links to field sales/service

Back EndServer

Customers

Server

Telephone Cable line

Gateway(s) PC & peripherals Entertainment

Server

Field Service

Temp. Sensor

Body

Data CommunicationTwo way

AC or heat

Pump

monitorSecurity Sensor


Two way White goods

Documents

C01 1 Overview