Evolution of Wireless Mobile Communications (I)2011. 4.25HyungHyung-Jin Choi Sungkyunkwan doc

Multiple Access Scheme Multiple Access Scheme – – FDMA FDMAor channels AMPS and other analog cellular systems Power T ime Frequency... connects cellular system to Public Switched Telepho

Evolution of Wireless Mobile Communications (I)

2011 4.25

Hyung Hyung Jin Jin Choi Choi Sungkyunkwan

Sungkyunkwan University University

Evolution of Wireless Mobile Communications

Multiple Access Scheme Multiple Access Scheme – – FDMA FDMA

or channels

(AMPS) and other analog cellular systems

Power

T ime

Frequency

AMPS AMPS – – an Example of Analog System an Example of Analog System

 Developed by Bell Labs in the 1970s and first used commercially in the United States in 1983

It operates in the 800 MHz band (1G) by AT&T

 Narrowband Advanced Mobile Phone System : BW=10kHz

 Developed by Motorola as an interim technology between analog and digital It has

up to three times greater capacity than AMPS and operates in the 800 MHz range

Cell Design in Cellular Telephone Systems

R :Cell radius

D :Distance between adjacent co-channel cell

n :Propagation attenuation factor

Co-channel reuse ratio Q

Signal to Interference power ratio

N

i i

Cellular Telephone Systems Cellular Telephone Systems Fundamentals Fundamentals

 serves mobile users in each cell /bridge between mobile unit and MSC

 controls base stations, call initiation & routing, handoffs, etc.

 connects cellular system to Public Switched Telephone Network (PSTN)

 Standard mechanism used by all mobiles

 Defines 4 different channels to be used by a mobile unit

 Forward/reverse voice channels - FVC/RVC

− Full Duplex communication

 Forward/reverse control channels - FCC/RCC

− call initiation & setup

− makes up 5% of total # of available channels (AMPS)

 One cell contains 10 to 60 voice channels and only 1 to 3 control channel pairs (F+R) (AMPS)

 MSC broadcasts call request from PSTN over all FCC's of all base stations – to find the mobile user

Cellular Telephone Systems Cellular Telephone Systems Fundamentals Fundamentals

/ MSC / : Receives call from PSTN Sends the requested MIN to all base station

< BS >: Transmits page (MIN) for specified user

< MS >: Received page and matches the MIN with its own MIN

< MS >: Acknowledges receipt of MIN and sends ESN and Station Class Mark

< BS >: Receives MIN, ESN, Station Class Mark and passes to MSC

< BS >: Receives MIN, ESN, Station Class Mark and passes to MSC

/ MSC / : Verifies that the mobile has a valid MIN,ESN pair

< BS >: Transmits data message for mobile to move to specific voice channel

< MS >: Receives data messages to move to specified voice channel

/ MSC / : Connects the mobile with the calling party on the PSTN

< BS , MS >: Begin voice Transmission <-> Begin voice Reception

2G Technologies

in 1992

 IS-54: FDMA/TDMA access mode

 IS-95: CDMA access mode

re-named as PDC (Personal Digital Cellular)

(PCS 1900):

Multiple Access Scheme Multiple Access Scheme – – TDMA TDMA

the signal into different time slots.

But the time between these bursts for a single mobile phone user is very short

Power

Time

Frequenc y

D D AMPS AMPS

 Digital AMPS is a variation of AMPS Uses 3-timeslot variation of TDMA, also known

as Interim Standard-54 (IS-54) Is an upgrade of the analogue AMPS

 D-AMPS (IS-54) employs the same 30 kHz channel spacing and frequency bands (824-849 and 869-894 MHz) as AMPS By using TDMA instead of FDMA, IS-54

increases the number of users from 1 to 3 per channel (up to 10 with enhanced

TDMA)

 AMPS/D-AMPS infrastructure can support use of either analogue AMPS phone or digital D-AMPS phones This is because the FCC mandated only that digital cellular

in the U.S must act in a dual-mode capacity with analogue Both operate in the 800 MHz band

PDC & PCS

1991

(full-rate) or 6-timeslot 5.6 kbit/s (half-rate) voice codecs.

services in Canada, Mexico and the United States

services and data delivery using digital modulation

(Conference of European Post and Telecommunication)

under ETSI(European telecommunication Standards Institute)

“ Global System for Mobile communication “

One hyper-frame contains 2048 super-frames which is equivalent to 2,715,648 TDMA frames.

One super-frame contains 1326 TDMA frames (6.12 seconds) can either carry 51 of 26-Multiframes or 26 of 51-Multiframes.

0 1 2 3 4 5 6 7

TS’s periodicity = 4.615ms

The Signaling Frame Structure is a multi-frame of 51 frames to accommodate control channels (FCCH, SCH, BCCH, CCCH) in the downlink and random access (RACH) in the uplink.

This frame structure uses Traffic Channel Frame Structure26 frames to build a multi frame Frames 0 to 11 and 13 to 24 carry speech or user data Frame 12 is used as SACCH, Frame 25 is idle, allowing the base station to measure field strengths from mobiles in other cells, when needed for handovers.

A set of 8 TDMA slots is called a frame In GSM, the terminal transmits and receives during different times slots.

an unconscious preference

provide secure data encryption give GSM advantages

Multiple Access Scheme Multiple Access Scheme – – CDMA CDMA

“multiple access”

bandwidth and any user can gain access to a pool of channels (one common

only by interference (soft capacity)

spreading gain

Walsh Code )

CDMA vs GSM

(Code Division Multiple Access)

GSM (Global System for Mobile Com.)

CDMA vs GSM

History of CDMA

station design

Qualcomm

world in 1996

CDMA vs TDMA

Code

Time Time

Freq Freq.

IS IS 95 CDMA Channel Structure 95 CDMA Channel Structure

Pilot Channel

(All 0's)

Walsh Function 0

PN Chip.

1.2288 Mcps

Code Symbol

Modulation Symbol

Modulation Symbol Encoder

R=1/2 K=9

Sync Channel

bits

Symbol Repetition

Block

1.2 kbps 2.4 ksps 4.8 ksps 4.8 ksps

Convolutional Encoder R=1/2 K=9

Paging Channel

bits

Symbol Repetition

Block Interleaver

Walsh Function 32

PN Chip.

1.2288 Mcps

A 9.6 kbps

4.8 kbps

19.2 ksps 9.6 ksps

19.2 ksps 19.2 ksps

Code Symbol

Modulation Symbol

Modulation Symbol

Long Code Generator

Long Code Mask for Paging Channel p

Decimator 1.2288 Mcps

19.2 ksps

IS IS 95 CDMA Channel Structure 95 CDMA Channel Structure

IS IS 95 CDMA Channel Structure 95 CDMA Channel Structure

IS IS 95 CDMA Channel Structure 95 CDMA Channel Structure

The concept of CDMA

Encoding in CDMA : Walsh channelization

1 - 1

- 1 - 1

-slot 0 channel output

slot 1 channel output

channel output

sender

code

data bits

1 - 1

- 1 - 1

-slot 0 channel output

slot 1 channel output

receiver

code

received input

, 1

M

i m

Z c D

M

=

⋅

=∑

CDMA CDMA – – Receiver Architecture Receiver Architecture

individual path signals of the multipath

∑

CDMA

internet etc using their mobile phone

packet-switching network equipments

received

physical channel dynamically on-need basis

interface error coding schemes and allocation of multiple timeslots

offering a new physical layer

than by creating new one

adaptation and incremental redundancy techniques

Comparison between Multiple Access Schemes

Frequency Reuse

Mobile Power

Standard IS-95A,SP3384 IS-54/136 IS-54 Based EIA-53.3

Speech Coder

-Diversity Time, Space, Freq Time, Space Time, Space Space

Development from 2G to 3G

Global strategy based on W-CDMA and EDGE networks, common IP based network, and dual mode W-CDMA/EDGE phones.

Converged TDMA/GSM

family of technologies

will have dominant market

share (~80 percent).

W-CDMA and cdma2000 will be optional modes in one spec Basic phones will be one or the other.

Global phones will have both.

IMT IMT 2000 2000

telecommunications defined by the International Telecommunication Union

data, all in mobile environments

5.8 Mbit/sec on the uplink with HSPA+)

network capacity through improved spectral efficiency

2G vs 3G

Service Low-speed Data service(Voice) High-quality Data service(Multi-media)

User Customer > Customer Customer<->Customer, IP<-> Customer Traffic trend Land to Mobile Mobile to Land

Mobility domestic, limited global roaming Global roaming

Mobility domestic, limited global roaming Global roaming

1840 ~ 1870MHz

Minimum

3G Technologies

※

※ Domestic (Korea) CDMA Operators

Relatively difficult ( Synchronous BS considers time- offset of neighbor BS’s PN code)

System developer Ericsson, Nokia, NTT DoCoMo Qualcomm, Lucent, Motorola

CDMA2000 (3GPP2)

Features

CDMA

data between mobile phones and cell sites

CDMA2000 (3GPP2)

CDMA2000 (3GPP2)

Difference between IS Difference between IS 95 and CDMA2000 95 and CDMA2000

Difference between IS Difference between IS 95 and CDMA2000 95 and CDMA2000

CDMA2000 Specification

transmission range and capacity

Fundamental, Supplemental, and Dedicated Control Channels

delay

CDMA2000 Specification

REVERSE CDMA CHANNEL (1.25 MHz or 5MHz channel received by base station)

Access

Channel

Reverse Traffic Channel (RC 1 or 2)

Enhanced Access Channel Operation

Reverse Common Control Channel Operation

Reverse Traffic Channel Operation (RC 3 to 6)

Reverse Fundamental Channel

0 to 7 Reverse Supplemental Code channels

Reverse Pilot Channel

Enhanced Access Channel

Reverse Pilot Channel

Reverse Common Control Channel

Reverse Pilot Channel

0 or 1 Reverse Dedicated Control Channel

0 or 1 Reverse Fundamental Channel

0 or 2 Reverse Supplemental Channel Reverse Power Control Subchannel

CDMA2000 Specification

CDMA2000 Specification

Forward CDMA CHANNEL For Spreading Rates 1 and 3(SR1 and SR3)

Common

Assignment

Channels

Common Power Control Channels

Pilot Channels

Common Control Channels

Sync Channel

Traffic Channels

Broadcast Channels

Paging Channels (SR1)

Quick Paging Channels

Forward

Pilot

Channels

Transmit Diversity Pilot Channels

Auxiliary Pilot Channels

Auxiliary Transmit Diversity Pilot Channels

0-1 Dedicated Control Channel

0-1 Fundamental Channel

Power Control Subchannel

0-7 Supplemental Code Channels (Radio Configurations 1-2)

0-2 Supplemental Channels (Radio Configurations

3-9)

CDMA2000 Standardization: TR45.5

CDMA2000 Standardization: 3GPP2 TSG CDMA2000 Standardization: 3GPP2 TSG C C

CDMA2000 1xEV CDMA2000 1xEV DO/DV DO/DV

CDMA2000 1xEV

CDMA2000 1xEV DO DO

CDMA2000 1xEV Family Standardization

mobility data efficiency

scheduling technique more significant than FIFO)

improving the capacity, data speeds, and overall performance and capability

of both real-time and non-real-time modes

Migration Paths For CDMA2000

EVDO Basic Concepts

Sector

Transmit

Sector Transmit

Pilot Channel Paging Channel Sync Channel

Total Traffic Unused Margin

IS-95 Forward Link Structure Time

EVDO Techniques

EVDO Techniques

transmission

EVDO Techniques

it introduces additional interference in the forward link

combining of traffic channels

Adaptive Modulation and Coding (AMC)

EV EV DV DV

EV EV DO/EV DO/EV DV DV

different pilot structures, reverse link silence periods, improved control

channels, etc.

not require a SS7 network and complex network switches such as a mobile switching center (MSC)

whereas the EV-DO equipment and mobile application-specific integrated

circuits (ASIC) were available and tested by the time the EV-DV standard was completed

been implemented.

HSDPA/HSUPA DL: 14.4 Mbps UL: 5.76 Mbps

HSPA Evolution DL: 28 Mbps UL: 11.5 Mbps

3GPP GSM EDGE Radio Access Network Evolution

3GPP UMTS Radio Access Network Evolution

UL: 384 kbps

In 5 MHz

LTE DL: 100 Mbps UL: 50 Mbps

In 1.25 MHz

EVDO Rev B DL: 14.7 Mbps UL: 4.9 Mbps

In 5 MHz

EVDO Rev C DL: 100 Mbps UL: 50 Mbps

In 20 MHz

3GPP Long Term Evolution

CDMA2000 Evolution